INSULIN SENSITIZATION TO SLOW DOWN PUBERTAL TEMPO AND TO AUGMENT PUBERTAL GROWTH

Background and Summary

BACKGROUND OF THE INVENTION

A. FIELD OF THE INVENTION

The present invention relates to a treatment to slow down pubertal progression in girls and more particularly to a system and method to slow down pubertal progression or to delay menarche in girls by means of insulin sensitization. The invention provides an insulin sensitizer treatment to prevent early puberty in girls with precocious pubarche (PP). The insulin sensitizers can be used to delay puberty in such PP girls.

B. DESCRIPTION OF THE RELATED ART

The duration of puberty in girls (time from B2 (breast stage 2) to menarche (Zurlo de Mirotti et al, Rev Fac Cien Med Univ Nac Cordoba. 1995; 53 Suppl: 7-15. Related Articles)) is variable. Factors modulating the tempo of pubertal progression were up to now essentially unknown. On the other hand there is a clear need in the art to understand these factors and for a treatment to slow down pubertal progression in patients in need thereof.

For instance early menarche is a well-established risk factor for female breast cancer (Apter D, Reinila M, Vihko R. Int J Cancer. 1989 Nov 15; 44(5):783-7; Stoll BA. Breast Cancer Res Treat. 1998 Jun; 49(3):lS7-93; De-Stavola,-B-L American-Journal- of-Epidemiology. 2004; 159(7): 671-682 and Key TJ Mutat Res. 1995 Dec; 333(1- 2): 59-67), and breast cancer is the most common cause of cancer death in women worldwide. Early menarche is also a risk factor for ovarian cancer (S. Franceschi et al, American Journal of Epidemiology, VoI 115, Issue 5 714-719, 1982; XO Shu et al., Cancer Research, VoI 49, Issue 13 3670-3674), for uterine leiomyomata (Marshall LM

et al, Fertil Steril. 1998 Sep; 70(3):432-9 and Fred F. Kadlubar et al. Cancer Epidemiology Biomarkers & Prevention Vol. 12, 327-331, April 2003, for pancreatic cancer (Fernandez E et al., Int J Cancer. 1995 JuI 4;62(l):l l-4) and for endometriosis (Daniel W. Cramer and Stacey A. Missmer Annals of the New York Academy of Sciences 955:11-22 (2002)). Conversely, a late menarche has been associated with reduced risk for subsequent breast cancer (Petridou E, et al, Int J Cancer. 1996 Oct 9;6S(2):193-S.).

Furthermore it has been shown that some girls with early-normal onset of puberty are at risk for a rapid pubertal progression and a reduced adult height (L Ibanez et al Pediatrics

Vol. 106 No. 5 November 2000, p. e72); precocious onset and progression of puberty are generally known to induce an accelerated bone maturation and to lead to an adult height below genetic target range.

Thus, there is a need in the art for a treatment to prevent rapid pubertal progression, early menarche or loss of pubertal height gain in girls, in particular in those girls at risk for an unusually fast progression of puberty. By the present invention we can fulfil this need, since we now surprisingly found that insulin -sensitization slows down the tempo of sexual maturation or pubertal progression in a mammal, more particularly in human boys or girls.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a novel method of treatment to delay the onset or to slow down the progression of sexual maturation or puberty in warm-blooded mammals in need thereof, more particularly in humans in need thereof, with a insulin- sensitizing agent, such as metformin.

SUMMARY OF THE INVENTION

The present invention solves a problem of the related art of rapidly progressing puberty in warm-blooded mammals, in particular in human boys or girls. It was surprisingly found that modulation of insulin signalling and more particularly that insulin-

sensitization is effective to modulate the duration of puberty and by consequence to prolong pubertal growth and to augment adult height.

In accordance with the purpose of the invention, as embodied and broadly described herein, the invention is broadly drawn to a new method of prevention or treatment of rapidly progressive puberty, more particularly of slowing down the tempo of puberty and thereby augmenting pubertal height gain.

Accordingly, the present invention is directed to methods of treating girls at risk for rapidly progressive puberty, comprising administering to a girl in need of such treatment an effective amount of insulin-sensitizer. For this treatment an insulin sensitizer or a combination of insulin sensitizers can be used. The insulin sensitizer or the insulin-sensitizing combination can for instance be administered orally.

One aspect of the invention comprises, the use of at least one insulin-sensitizing agent for instance an agent selected from the group consisting of metformin, rosiglitazone, pioglitazone, troglitazone, englitazone, targretin, phenformin, CLX-0921, BLX- 1002, tesaglitazar, oxeglitazar and buformin or pharmaceutically acceptable salts, solvates or polymorphs thereof for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal, preferably a female mammal and in particular for treatment of rapidly progressive puberty or for prevention of early menarche in girls.

The insulin-sensitizing agent in use for the present invention can be a compound selected of the group consisting of insulin-sensitizing compounds of the biguanide or the glitazone (thiazolidinedione) class or pharmaceutically acceptable salts, solvates or polymorphs thereof.

The insulin-sensitizing agent in use for the present invention can be a compound selected of the group consisting of insulin-sensitizing compounds of the general structure formula:

or of the general structure formula

The compounds for use according to present invention can be a thiazolidinedione compound selected of de group consisting of 5-[[4-[2-(3-methyl-2- pyridinyl)ethoxy]phenyl]methyl]- 2,4-Thiazolidinedione, 5-[[4-[2-(5-ethyl-2-pyridinyl)- 2-hydroxyethoxy]phenyl]methyl]-2,4-Thiazolidinedione, 5-[[4-[2-[5-(l-hydroxyethyl)- 2-pyridinyl]ethoxy]phenyl]methyl]-2,4-Thiazolidinedione, 5-[[4-[2-(5-acetyl-2- pyridinyl)ethoxy]phenyl]methyl]-2,4-Thiazolidinedione, 5-[[4-[2(methyl-2- pyridinylamino)ethoxy]phenyl]- methyl]-2,4-thiazolidine dione maleate, 5-[4-(l- methylcyclohexylmethoxy)beiizyl]-thiazolidine-2,4-dione and ([+ or -])-5-[4-(6- methoxy- 1 -H-benzimidazol-2-ylmethoxy) benzyl[thiazoline-2,4-dione hydrochloride (CI-1037/CS-011) or pharmaceutically acceptable salts, solvates or polymorphs thereof.

Other suitable insulin sensitizers for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal according to present invention are the PPARγ agonist thiazolidinediones (e.g., rosiglitazone, pioglitazone, troglitazone, MK 767 (KRP-297), MCC-555, netoglitazone, balaglitazone, rivoglitazone, CLX-0921, R-483, NEP-221, NIP-223, DRF-2189) and the non-thiazolidinediones that can activate any combination of PPAR.gamma., PPAR.alpha. and PPAR.delta. (e.g., JTT-501, LSNS62, DRF 4832, LM 4156, LY 510929, LY 519818, TY 51501, X 334, tesaglitazar, farglitazar, GW- 7282, TAK-559, T-131, RG-12525, LY-510929, LY-519818, BMS-298585, DRF-2725,

GW-1536, GI-262570, TZDl 8 (Merck), DRF-2655, and the like), certain tyrosine- based derivatives (e.g., GW1929, GW7845), phenylacetic acid-based derivatives, phenoxazine phenyl propanoic acid derivatives (e.g., DRF 2725, DRF 2189), cinamniic

In another embodiment of present invention the insulin-sensitizing agent in use for the present invention is Conjugated Linoleic Acid (CLA) or aminoguanidine or pharmaceutically acceptable salts, solvates or polymorphs thereof.

The composition to treat of present invention can further comprise a suitable pharmaceutical carrier and/or excipient.

Another aspect of the invention is a method of prophylaxis or treatment of abnormal progression of puberty, more particularly of rapidly progressive puberty in a mammal, more particularly in a human boy or girl. The duration of puberty can be prolonged or menarche can be delayed in a female mammal by a treatment with at least one an insulin-sensitizing agent, for instance an insulin-sensitizing agent described above.

The insulin-sensitizing agents metformin, rosiglitazone, pioglitazone, , troglitazone, englitazone, targretin, pheiiformin, CLX-0921, BLX- 1002, tesaglitazar, oxeglitazar or pharmaceutically acceptable salts, solvates or polymorphs thereof, are particularly suitable for use in this treatment.

In yet another aspect of present invention the duration of puberty is prolonged or menarche is delayed by treatment of a female mammal with an insulin-sensitizing biguanide or thiazolidinedione or both.

hi a particular object of present invention the duration of puberty is prolonged or menarche is delayed in obese girls by the treatment of present invention.

In still another aspect of the invention the duration of puberty is prolonged or menarche is delayed in non-obese girls by the treatment of present invention.

The treatment to prolong the duration of puberty or to delay menarche can be associated with several benefits such as: reduction of pubertal weight gain (see weight, BMI, BMI SDS); a less adipose body composition (see Fat and Lean Mass); an increment of fasting glucose/insulin ratio and/or increment of circulating Sex-Hormone Binding Globulin (SHBG); a less atherogenic lipid profile (see HDL-cholesterol and triglycerides); no need for raising IGF-I into high-normal (1-2 SD) or supra-normal (>2 SD) range; no need for silencing the gonadotropic axis or adrenal androgen production (see LH, FSH, DHEAS); no need for suppressing the pubertal development of the internal genitalia (see uterine and ovarian size); no need for inhibiting the pubertal increment in bone mineral density (see BMD)

In yet another embodiment of present invention the insulin-sensitizing compounds are used as part of a treatment or a medication to increase pubertal height gain in mammals, preferably humans and yet more preferably girls. Further scope of applicability of the present invention will become apparent from the detailed description given herein below. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawing Description

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1. provides a summary of the study design.

FIG. 2. is a longitudinal display of IGF-I and SHBG levels, percent body fat, and gains in height above baseline, in metformin-treated versus untreated girls. Means ± 95% CI are displayed. * indicates P<0.05 for difference in time-trends between the two groups by repeated measures ANOVA. # indicates P<0.05 at each time-point by unpaired t-test.

FIG. 3. demonstrates that a treatment with metformin delays the occurrence of menarche in girls who were bom with a low weight for the gestational age and who started puberty at an early-normal age (8 yr) Left panel: Time from onset of breast development (B2) to menarche in low- birthweight girls with early-normal puberty. Untreated girls and metformin-treated girls had a similar age at B2. Metformin treatment was accompanied by a slower progress to menarche. Right panel: 42 mo after study stait, metformin-treated girls are taller than the untreated controls, and their post- menarcheal growth velocity is still faster (Table 2). The horizontal bars display the medians for each group.

FIG. 4. Pubertal stage, height, lean body mass, IGF-I levels, percent total body fat, and abdominal fat mass in low-birth weight girls with precocious pubarche, who remained untreated (n=19) or received metformin (n=19) for 24 mo. Means ± 95% CI are displayed. *P<0.01 for difference in rate of change between subgroups by repeated measures ANOVA.

Detailed Description

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The following detailed description of the invention refers to the accompanying drawings. Also, the following detailed description does not limit the invention.

Menarche heralds the end of epiphysial growth and the beginning of reproductive life. If onset of puberty occurs within the age range of ~8-13 yr (Herman-Giddens ME, et al 1997 Pediatrics. 99:505-512; Kaplowitz PB et al. 1999 Pediatrics. 104:936-941 and Parent AS, et al 2003 Endocr Rev. 24:668-93), then an earlier onset (breast budding)

tends to be followed by a slower progression throughout puberty. Accordingly, the variation in the age at pubertal onset is broader than at menarche (Marti-Henneberg C and Vizmanos B. 1997 J Pediatr. 131:618-621 and Ibanez L, et al. 2000 Pediatrics. 106:E72).

Little is known on the mechanism that compensates a shorter pre-puberty by a longer puberty up to menarche. This compensatory phenomenon fails frequently in girls who grew up through the sequence of a growth restraint before birth, then a catch-up growth in infancy, and subsequently a pubertal onset at an early-normal age (8-9 yr); consequently, such girls are at risk, not only for early menarche, but also for a rapid growth arrest and short adult stature (Ibanez L, et al. 2000 Pediatrics. 106:E72.).

At present, there is no therapy for most of these girls, as their puberty starts too late for conventional GnRH-agonist therapy (Bouvattier C, et al 1999 J Clin Endocrinol Metab. 84:3575-3578), and as their stature during puberty is too tall to consider growth hormone therapy.

We proposed that hyperinsulinmic insulin resistance underpins the failure to lower the pubertal tempo and to normalize the pubertal growth spurt in low-birth weight girls with early-normal onset of puberty. We have now tested this hypothesis by exploring the effects of pubertal insulin sensitization with metformin.

A. DEFINITIONS

Puberty is the phase of sexual maturation and body growth that occurs between (prepubertal) childhood and (postpubertal) adulthood. In boys, the onset of puberty is classically defined by an increment of testicular volume to 4 ml or more. In girls, the onset of puberty is classically defined by the appearance of breast budding. The duration of puberty in girls has been defined, for purpose of this application and by the man skilled in the art, as time from B2 (breast stage 2 by Tanner score) to menarche (this is the first menstrual bleeding) (Zurlo de Mirotti et al, Rev Fac Cien Med Univ Nac Cordoba. 1995; 53 Suppl: 7-15. Related Articles).

A rapidly progressive puberty is in this application for humans, more particularly for girls, in the meaning of a short duration of puberty relative to the timing of its onset; for example, a pubertal duration of <2.3 yr after a pubertal onset prior to age 9 yr. Such a rapidly progressive puberty causes a rapid progression of bone maturation and leads to an adult height below the genetic target range. Hence, a reduction of pubertal height gain is an epiphenomenon of a rapidly progressive puberty.

"Monotherapy" in the present application relates to the administration of a single active agent for the treatment to control the progression of puberty. It relates here to the administration of an insulin-sensitizing agent. The administration of more than one insulin-sensitizing agent is also considered to be a monotherapy.

"Insulin-sensitizing agent" in the present application relates to compounds reversing the effects of insulin resistance. Examples are metformin, troglitazone, rosiglitazone, pioglitazone.

As used herein the term 'pharmaceutically acceptable ¹ embraces both human and veterinary use: for example the term 'pharmaceutically acceptable' embraces a medically acceptable compound.

B. EXAMPLES

Experimental 1 Study on metformin therapy during puberty

Delay ofmenarche, prolonged pubertal growth and augmentation of adult height

OVERVIEW OF THE STUDY

Context and Objective: Low-birth weight (LBW) girls who enter puberty earlier

(around 8-9 years) tend to have earlier menarche, earlier growth arrest, and a shorter adult stature. At present, there is no therapy for most of these girls. In LBW girls with early puberty, hyperinsulinniic insulin resistance could underpin their rapid

transit through puberty and their loss of adult stature. We explored the effects of insulin- sensitization with metformin during puberty.

Setting, Design, and Patients: In an open-labelled, prospective study, 22 LBW girls (BW below -1.5 Standard deviation Score [SDS] for gestational age) with early-normal puberty (stage 2 breast development (B2) at age 8-9 years) were randomized to remain untreated [n=12] or to receive metformin [850 mg/d; n=10] for 36 mo (mean age at start = 9.0 yr). All girls remained untreated between 36 and 42 mo.

Main outcome measures: Pubertal growth, body composition by absorptiometry, uterine-ovarian size by ultrasound, fasting insulin, glucose, lipids, leptin, insulin- like growth factor- 1 (IGF-I) and IGF-binding protein- 1 (IGFBP-I).

Results: Metformin treatment resulted in a longer duration from B2 to menarche (p<0.01; median difference +1.0 yr), taller near-adult height (pθ.01) and leaner body composition (PO.001). Metformin was also associated with lower insulin resistance, leptin and IGF-I levels, higher SHBG and IGFBP-I levels, and with a more favourable lipid profile. Bone mineral density and uterine-ovarian growth were unaffected.

Conclusion: Metformin treatment for 36 mo in LBW girls with early-normal puberty normalized their pubertal progression to menarche and increased height gains up to adult stature. These data support the concept that insulin is a major co- determinant of the pubertal tempo and pubertal height gain in girls

DETAILS OF THE STUDY

Subjects

The study population consisted of 22 girls (Table 1).

Inclusion criteria were: [1] Birth weight below -1.5 Standard Deviation Score (SDS) for gestational age, which corresponds to a birth weight below 2.8 Kg in term Catalan

girls (this level of prenatal growth restraint being known to be associated with an early menarche and a reduced adult stature, if puberty starts at age 8-9 yr) (Ibanez L, et al. 2000, Pediatrics. 106:E72); [2] History of onset of breast development (Tanner stage 2 (Marshall WA, Tanner JM. 1969 Arch Dis Child. 44:291-303.) or B2) between age 8-9 yr, and less than 1 yr before study start; [3] Height at enrolment ≥ 1 SD above the midparental height SD for chronological age (Tanner JM, Whitehouse RH, Takaishi M. 1986, British children, 1965. Part π. Arch Dis Child. 41 :613-635.); [4] Bone age ≥ 1 yr above chronological age; [5] central and progressive puberty, as judged by gonadotropin responses to GnRH agonist (Ibanez L, et al. J Clin Endocrinol Metab. 78:30-35.) and by pubertal dimensions of the internal genitalia on ultrasound examination (Griffin IJ, et al. 1995 Pelvic ultrasound measurements in normal girls. Acta Paediatr. 84:536-543).

The exclusion criteria were: a family or personal history of diabetes mellitus; a history of precocious pubarche or the presence of other signs of androgen excess (Ibanez L, et al 1998 J Clin Endocrinol Metab. 83:3558-3662); evidence for thyroid dysfunction or glucose intolerance (The Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. 1997 Report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Diabetes Care. 20:1183-1197); intake of medication known to affect gonadal function or carbohydrate metabolism.

Study Design

In this open-labelled study (Figure 1), girls were randomized to remain untreated [Met (-); n=12] or to receive metformin [850 mg] once daily, at dinner time [Met (+); n=10] for a total of 36 mo. The randomization was performed according to the Gran Mos computer program (Institut Municipal d'Investigaciό Medica de Barcelona). Pubertal growth, body composition, uterine-ovarian size, and endocrine- metabolic markers were assessed 6-monthly between 0-36 mo. Thereafter, all girls remained untreated; 42mo after study start, one more auxological assessment was performed.

Compliance with the medication was assessed by counting the number of pills remaining at each visit. Moreover, at each visit, all families/patients confirmed by interview, their compliance.

Auxology

Birth weight data were transformed into SDS for gestational age (Ibanez L, et al. 1998 J Clin Endocrinol Metab. 83:3558-3662). Height was measured with a Harpenden stadiometer and transformed into SDS according to Tanner references (Tanner JM, Whitehouse RH, Takaishi M. 1986 Standards from birth to maturity for height, weight, height velocity and weight velocity: British children, 1965. Part II. Arch Dis Child. 41:613-635.), which are applicable to Catalan girls (de Ia Puente ML, et al. 1997 Ann Hum Biol. 24:435-452). Target height was defined as mid-parental height, adjusted for female gender. Body mass index (BMI) was calculated as the ratio of weight (in Kg) to height squared (in meter), and was transformed into SDS for chronological age (Ibanez L, et al. 2003 Clin Endocrinol. 58:372-379); bone age was assessed by a single observer (L.I.), according to the method of Greulich and PyIe (Greulich WW, PyIe SI. Radiographic atlas of skeletal development of the hand and wrist. Standford: Stanford University Press; 1959.).

Ultrasonography

The ultrasound examinations were performed in full-bladder state. Scans were obtained by a single observer using an Acuson Sequoia 512 (Mountain λ^iew, CA ₅ USA) with a 4-6 MHz multifrequency sector probe. Uterine length was measured from the top of the fundus to the cervix. Longitudinal and transverse views of the ovaries were obtained for measurement of length, breadth and depth of each ovary. Ovarian volume (right and left) was calculated using the formula for a modified prolate ellipsoid (depth x breadth x length/2) (Griffin IJ, et al. Acta Paediatr. 84:536- 543, Ibanez L, et al. 2000 Reduced uterine and ovarian size in adolescent girls born small for gestational age. Pediatr Res. 47:575-577.).

Body Composition

Body composition was assessed by dual-energy X-ray absorptiometry (DXA) at study start and every 6 mo, with a Lunar Prodigy coupled to Lunar software

(version 3.4/3.5, Lunar Corp, Madison, WI, USA) (Ibanez L, et al. 2003. Clin Endocrinol. 58:372-379). Absolute (Kg) whole body fat and lean mass were assessed, as well as fat content in the abdominal region, which was defined as the area between the

dome of the diaphragm (cephalad limit) and the top of the great trochanter (caudal limit) (Taylor RW, et al. Am J Clin Nutr. 67:44-49). Total irradiation dose per assessment was 0.1 mSievert. Coefficients of variation (CVs) for scanning precision are 2.0% and 2.6% for fat and lean body mass (Kiebzak GM, et al. J Clin Densitometry. 3:35-41), with an intra-individual CV for abdominal fat of 0.7%.

Endocrine-Metabolic Assessment, Assays and Statistics

Fasting serum insulin, sex hormone-binding globulin (SHBG), insulin-like growth factor-I (IGF-I), HDL- and LDL-cholesterol and triglycerides were assessed 6- monthly between 0-36 mo, together with indices of hepatic and renal function, as additional safety variables. Serum leptin and IGF-I-binding protein- 1 (IGFBP-I) were determined at 0 and 24 mo. Fasting insulin resistance was estimated from fasting insulin and glucose levels using the Homeostasis Model Assessment (HOMA) (29); the values in the study patients were compared to those of age- and pubertal-stage matched controls from the same population (Potau N, et al. 2003 Clin Endocrinol. 59:756-762.).

Serum insulin, IGF-I and SHBG were assayed as described (Ibanez L, de Zegher F. 2004 J Clin Endocrinol Metab. 89:1592-1597; Ibanez L, et al. 2000 Horni Res. 54:192-197 , Ibanez L, et al. 1999 Pediatr Res. 46: 320-322 and Llop-Vinolas

D, et al. 2004 Acta Paediatr. 93:874-879); leptin was measured by RLA

(Linco, St. Louis, MO, USA), as described (Ibanez L, et al. 2000. Horm Res. 54:192-

197); IGFBP-I was measured by quantitative immunometric assay (Medix-Biochemma,

OuIu, Finland), as described (Ibanez L, et al 1999 Pediatr Res. 46: 320-322.). Samples were kept frozen until assay.

For uniformity, results are expressed as mean ± SEM, unless mentioned otherwise. Differences in time-trends for multiply repeated measures (Figure 2: IGF-I, SHBG, % body fat and height gain) between the 2 groups were tested by repeated measures ANOVA. Two-sided t-tests (paired or unpaired, as appropriate) were used for statistical comparisons between groups; significance level was set at p<0.05.

Results

Table 1 shows the endocrine-metabolic, body composition and ultrasound results (0-36 mo); Table 2 summarizes the auxological findings after 42 mo. Baseline characteristics were similar in untreated and metfoπnin-treated girls; without being frankly obese (mean BMI below +2 SD), both subgroups were adipose (high fat fraction for a given BMI) and had high serum leptin concentrations (on average >2- fold higher than the reference mean).

Metformin treatment was associated with relatively lower insulin, leptin and IGF-I levels, higher SHBG and IGFBP-I levels, a less atherogenic lipid profile, and a leaner body composition (Table 1; Figure 2). Neither gain in bone mineral density nor growth of the internal genitalia was detectably altered.

Figure 3 (left panel) depicts the effect of nietfonnin on the duration of puberty, as judged by the timespan from B2 to menarche. Untreated and metfoπnin-treated girls had a similar mean age at start of B2 (8.7 vs 8.6 yr) and at start of study (9.1 vs 9.0 yr), but diverged in time-to-menarche: a median 2.0 yr versus 3.0 yr (p<0.01). Accordingly, metformin treatment was accompanied by a prolonged pubertal height gain (Table 2; Figure 2).

Figure 3 (right panel) shows that metformin treatment increases (p<0.01) near- adult height (relative to target height), as inferred from the last available height at 42 mo. The ultimate effect of pubertal nietfonnin treatment on adult height is expected to be slightly more pronounced, since all untreated girls have virtually stopped growing (height velocity <2 cm/y), while 4 of the 10 metfonnin-treated girls were still growing at a velocity above 2 cm/yr at 42 months (Table 2; pO.Ol). Metformin treatment was well-tolerated; indices of hepatic and renal function remained stable throughout the study.

Discussion

The results of the untreated girls in this prospective study confirm the retrospective observation (Ibanez L, et al. Pediatrics. 106:E72) that LBW girls with

an early-normal onset of breast development tend to transit rapidly through puberty and to end up with a stature below target height. After comparison with the findings in untreated girls, the results from the treated girls indicate that insulin-sensitizing therapy with metformin (for 36 mo) normalizes the timing of menarche (Marti- Henneberg C, Vizmanos B. 1997 J Pediatr. 131:618-621, Llop-Vinolas D, et al. 2004 Acta Paediatr. 93:874-879.), and prolongs and augments pubertal growth up to adult height. Metformin treatment also results in a leaner body composition and less adverse lipid profile. The mechanisms whereby metformin exerts its normalizing effects on pubertal progression and growth in this study population are likely to be multiple and interlinked. In girls, the rise in serum leptin concentrations during puberty is strongly related to fat mass and are inversely related to age at menarche (Grumbach MM. 2002 Horm Res. 57 (Suppl 2):2-14., Apter D. 2003 Ann N Y Acad Sci. 997:64-76, Matkovic V, Ilich JA, Skugor M, Badenhop NE, Goel P, Clairmont A, Klisovic D, Nahhas RW, Landoll JD. 1997 Leptin is inversely related to age at menarche in human females. J Clin Endocrinol Metab. 82:3239-3245, Wilson ME, et al. 2003 J Clin Endocrinol Metab.88:4874-4883; Argente J, et al. 1997 J Pediatr. 313:833-838; Fors H, et al. 1999 J Clin Endocrinol Metab. 84:3586-3590; Li H, et al. 2005 J Clin Endocrinol Metab. 90:3659-3664). By reducing body adiposity (including abdominal fat mass) and thus leptinemia, metformin may attenuate the activity of the hypothalamic GnRH pulse generator Chan JL, Mantzoros CS. 2001 Pituitary. 4:87-92, Welt CK ₅ et al. 2004. New Engl J Med. 351:987-997), enhance the gonadal feedback suppression on LH secretion (Wilson ME, et al. 2003 J Clin Endocrinol Metab. 88:4874-4883), and decrease aromatase activity in ovarian granulosa cells (Kitawaki J, et al. 1999 MoI Hum Reprod. 8:708-713.). Alternatively, by reducing hyperinsulinmia and by concomitantly raising serum SHBG and IGFBP-I ₅ metformin may alter the unbound estrogen and IGF-I fractions that act upon receptive tissues, such as the endometrium and the growth plate. Metformin-induced decreases of both circulating insulin and IGF-I may also reduce aromatase activity and estrogen biosynthesis within the ovary (La Marca A, et al. 2002 Fertil Steril. 78:1234-1239, Poretsky L, et al. 1999 Endocr Rev. 20:535-582.). It remains to be determined whether metformin is also capable of normalizing the endocrine-metabolic state, the pubertal growth and the menarcheal

timing in other conditions of hyperinsulinmia and hyperleptinemia, such as simple obesity (Apter D. 2003. Ann N Y Acad Sci. 997:64-76, Shalitin S, Philip M. 2003 Int J Obes Relat Metab Disord. 27:869-874, Frontini MG, et al. 2003 Int J Obes. 27:1398- 1404., Adair LS, Gordon-Larsen P. 2001 Am J Public Health. 91:642-644, Demerath EW, et al. 2004 Am J Clin Nutr. 80:441-446 and Must A, et al. 2005 Pediatrics. 116: 620-627).

In conclusion, metformin treatment in LBW girls with an early-normal pubertal onset was found to normalize the pubertal progression to menarche and to increase pubertal height gain and adult stature. These data support the concept that insulin is a major co-determinant of the pubertal tempo and pubertal height gain in girls. To which extent this modulation is directly or indirectly exerted through the interplay of insulin resistance, SHBG, estrogen, IGF-I, IGFBP-I, leptin, lipids and body adiposity - among other factors — remains to be further elucidated.

Experimental 2 on metformin treatment to prevent early puberty in girls with precocious pubarche

OVERVIEW

Context and Objective: Girls with precocious pubarche (PP, pubic hair < 8 yr) are at high risk for early onset and rapid progression of puberty, in particular if their prenatal growth was restrained (low birth weight, LBW) and followed by rapid postnatal catchup of weight gain. We postulated that insulin resistance contributes to early onset and rapid progression of puberty in LBW-PP girls, and thus explored the puberty-delaying effects of insulin sensitization with metformin initiated shortly after PP diagnosis. Setting, Design, and Patients: The study population consisted of 38 prepubertal LBW girls with PP attributed to exaggerated adrenarche [mean BW 2.4 Kg; age 7.9 yr; body mass index (BMI) 18.4 Kg/m ² ]; these girls were randomly assigned to remain untreated (n=19) or to receive metformin (n=19; 425 mg/d) for 2 yr.

Main outcome measures: Pubertal staging, age at menarche, body composition by absorptiometry, fasting insulin, glucose, lipids, leptin, insulin-like growth factor- 1 (IGF-

1), IGF-binding protein-1 (IGFBP-I), testosterone, dehydroepiandrosterone-sulfate (DHEAS), testosterone, sex hormone-binding globulin (SHBG).

Results: Metformin treatment was associated with a less adipose body composition (and lower serum leptin levels) and with a 0.4 yr delay in the clinical onset of puberty (Tanner B2; 9.5 yr versus 9.1 yr; pθ.01). These findings were corroborated by a delay of at least 1 yr in the puberty-associated rise of circulating IGF-I (P<0.01). Available results also point to a metformin-associated delay of menarche (P<0.02); so far, gain in height and lean mass was not divergent between study subgroups.

Conclusion: The efficacy of early metformin treatment in PP girls is herewith extended to include not only a less adipose body composition after 2 yr, but also a less advanced onset of puberty, while height gain is maintained. These findings open the perspective that, ultimately, metformin treatment may also prove to heighten the short adult stature of LBW-PP girls.

DETAILS

Catalan girls with precocious pubarche (PP; pubic hair < 8 yr) due to exaggerated adrenarche are known to develop hyperinsulinmia of prepubertal onset and to present a rapidly progressive puberty with early-normal menarche (Ibanez L, et al. 1997 J Clin

Endocrinol Metab. 82:2283-2288 and Ibanez L, Jimenez R, de Zegher F. 2006

Pediatrics. 117:117-121). The PP girls at highest risk for both an early onset of puberty and a fast transit to post-menarche are those who were thin as fetus (low birth weight; LBW) and became adipose in childhood (Ibanez L, Jimenez R, de Zegher F. 2006

Pediatrics. 117:117-121 and Ibanez L, et al. 2003 CHn Endocrinol. 58:372-379); on average, these girls start puberty [Tanner breast stage 2; B2] at 9.4 yr and experience menarche at 11.5 yr (Ibanez L, Jimenez R, de Zegher F. 2006 Pediatrics. 117:117-121).

Among PP girls, those with LBW are also the most hyperinsulinmic and hyperleptinemic, and they have the lowest serum levels of sex hormone binding globulin (SHBG) and of insulin-like growth factor binding protein-1 (IGFBP-I) (Ibanez

L, Jimenez R, de Zegher F. 2006 Pediatrics. 117:117-121 ; Ibanez L, Potau N, de

Zegher F. 1999 Pediatr Res. 46: 320-322 and Ibanez L ₅ et al. 2000 Horm Res. 54:192- 197).

Both insulin and leptin are thought to accelerate the timing of pubertal onset and to upregulate the tempo of pubertal progression (Plant TM, Barker-Gibb MI. 2004 Hum Reprod Update.10: 67-77 and Welt CK, 2004 New Engl J Med. 351:987-997).

Hyperinsulinmia and -leptinemia are commonly present in obese girls and in LBW girls with early-normal onset of puberty [B2 at 8-9 yr], and may contribute to drive their rapid transit to post-menarche (Shalitin S, Philip M. 2003 Int J Obes Relat Metab

Disord. 27:869-874 and Matkovic V, et al. 1997 J Clin Endocrinol Metab. 82:3239- 3245).

We postulated that hyperinsulinmic insulin resistance contributes to early onset and rapid progression of puberty in LBW-PP girls, and thus explored the puberty-delaying effects of insulin sensitization with metformin initiated shortly after PP diagnosis.

Study Population & Methods Subjects and Ethics

The study population consisted of 38 LBW-PP girls (Table 3). The inclusion criteria were: [1] PP due to exaggerated adrenarche, as judged by high serum dehydroepiandrosterone-sulfate (DHEAS) and/or androstenedione levels (Ibanez L, Potau N, Francois I, de Zegher F. 1998 J CHn Endocrinol Metab. 83:3558-3662); [2] weight <2.9 kg at term birth (38-41 wk) or below -1 SD for gestational age at preterm birth (33-37 wk); [3] body mass index (BMI) <22 Kg/m ² ; [4] pre-puberty (Tanner Bl) (Marshall WA, Tanner JM. 1969 Arch Dis Child. 44:291-303). None of the girls had a family or personal history of diabetes mellitus, or presented evidence for thyroid dysfunction, glucose intolerance (The Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. 1997 Report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Diabetes Care. 20:1183-1197) or late-onset congenital adrenal hyperplasia ( New MI, et aL 1983 J Clin Endocrinol Metab. 56:320-325 and Mermejo LM, et al. 2005 J Clin Endocrinol Metab. 90:1287- 1293); none was receiving a medication known to affect gonadal function or carbohydrate metabolism.

The study protocol was registered under number ISRCTN84749320 and was approved by the Institutional Review Board of Barcelona University, Hospital of Sant Joan de Deu. Informed consent was obtained from parents, and assent from the girls.

Study Desig)i & Assessments

Girls were randomly assigned to remain untreated or to receive metformin (425 mg, once daily at dinner time) for 24 mo; further follow-up is ongoing (metformin dose 850 mg/d beyond 24 mo). The randomization list (1:1 ratio) was produced before study start (Gran Mos program; Barcelona Medical Research Institute); the investigators followed the sequence in this list; patients were consecutively included, as either untreated or treated, according to their position within this list; when deciding about a patient's inclusion, the investigators had no access to the next treatment assignment in the sequence. Clinical examination with pubertal staging was performed 6-monthly, together with assessment of body composition, fasting blood glucose and serum insulin, SHBG, DHEAS, androstenedione, testosterone and lipid profile. Serum leptin and IGF-I- binding protein- 1 (IGFBP-I) were determined at 0 and 24 mo. A single investigator (LI) assessed breast budding (B2) by palpation and, when appropriate, screened by history for an even more precise timing of B2 appearance within the 6 preceding months; age at menarche was derived by history.

Body Composition

Body composition was assessed by dual-energy x-ray absorptiometry with a Lunar Prodigy coupled to Lunar software (Lunar Corp, WI, USA). Absolute (Kg) whole body fat and lean mass were assessed, as well as fat content in the abdominal region, which was defined as the area between the dome of the diaphragm (cephalad limit) and the top of the great throcanter (caudal limit), as described (Ibanez L, et al. 2003 Clin Endocrinol. 58:372-379). Total radiation dose per examination was 0.1 mSievert. Coefficients of variation (CVs) for scanning precision are estimated to be 2.0% and 2.6% for fat and lean mass (Hologic, Waltham, MA) with an intra-individual CV for abdominal fat mass of 0.7% (Kiebzak GM, et al. 2000 J Clin Densitometry. 3:35-41.0). Indicative references for body composition are from 13 healthy Catalan schoolgirls (matched for age, pubertal status and body size) who were living in the same area.

Hormone Assays, Calculations and Statistics

Serum glucose was measured by the glucose oxidase method. Serum immunoreactive insulin, DHEAS, androstenedione, testosterone and SHBG were assayed as described (Ibanez L, et al. 2004 J Clin Endocrinol Metab. 89:4331 -4337). Serum leptin was measured by RIA (Linco, St. Louis, MO, USA) (5); IGFBP-I was measured by quantitative immunometric assay (Medix-Biochemma, OuIu, Finland) (Ibanez L, Potau N, de Zegher F. 1999 Pediatr Res. 46: 320-322); all methods had intra- and interassay coefficients of variation between 4-8% within the relevant concentration ranges. Fasting insulin sensitivity was estimated from fasting insulin and glucose levels using the homeostasis model assessment (HOMA-CIGMA Calculator program v2.00) (Levy JC, Matthews DR, Hermans MP. 1998 Diabetes Care. 21: 2191-2192). Samples were kept frozen at -2O ⁰ C until assay; markers in both groups were assayed at the same time. Data on birthweight and gestational age were obtained from hospital records and transformed into SD scores (Ibanez L, Potau N, Francois I, de Zegher F. 1998 J Clin Endocrinol Metab. 83:3558-3662).

Two-sided t-tests were performed to compare the total study population with the indicative references; t-tests were also performed to compare the changes within each treatment subgroup, and the 0-24 mo changes between the subgroups. Differences in longitudinal 6-monthly data between the 2 groups was tested by repeated measures ANOVA. For uniformity, all results are expressed as mean ± SEM. The level of statistical significance was set at p<0.05. Prepubertal, short-term results (0-6 mo) of part of this study population (n=33) have been reported previously (Ibanez L, et al. 2004 J Clin Endocrinol Metab. 89:4331-4337).

Results

Table 4 summarizes the main results at 0 and 24 mo. Baseline values of the study population were suggestive of insulin resistance, androgen excess, an atherogenic lipid profile, and an adipose body composition. After 24 mo, metformin-treated girls displayed less insulin resistance and less androgen excess, and had a less atherogenic lipid profile and a less adipose body composition than the untreated girls. Figure 4 highlights a selection of longitudinal findings. Between the subgroups, there is a striking difference in pubertal development, which is reflected in the respective IGF-I

patterns. Despite a slower course into and through puberty, the metformin-treated girls maintain their gains in height and lean mass, while they attenuate their fat excess. Metformin-treated girls entered into B2 approximately 0.4 yr after the untreated girls (9.5 ± 0.1 versus 9.1 ± 0.1; p<0.01). Preliminary results during the third study year indicate that metformin treatment is also associated with a delay of menarche: 5 of 19 untreated girls already experienced menarche, while this was so far the case in none of the 19 metformin-treated girls (p=0.016 by chi-square).

Metformin treatment was well tolerated; indices of hepatic and renal function remained unchanged throughout treatment.

Discussion

Longitudinal and cross-sectional studies have shown that LBW-PP girls are at risk for early onset of puberty and menses and, thereafter, for a relatively short stature and for further progression to anovulation and to hyperinsulinmic hyperandrogenism, which is a variant of PCOS (Ibanez L, Jimenez R, de Zegher F. 2006 Pediatrics. 117:117-121 , Ibanez L, Potau N, Francois I, de Zegher F. 199S J Clin Endocrinol Metab. 83:3558- 3662, Ibanez L, et al. 1993 J Clin Endocrinol Metab. 76:1599-1603., Ibanez L, de Zegher F, Potau N. 1999 J Clin Endocrinol Metab. 84:2691-2695 and Ghirri P, et al. 2001 Gynecol Endocrinol. 15:91-97). These sequential outcomes are thought to be partly attributable to hyperinsulinmic insulin resistance and its correlates, such as an adipose body composition (even in the absence of obesity), a pro-inflammatory state, high circulating leptin concentrations, adrenal hyperandrogenism, an atherogenic lipid profile, and low SHBG levels (Ibanez L, et al. 1997 J Clin Endocrinol Metab. 82:2283- 2288, Ibanez L, Jimenez R, de Zegher F. 2006 Pediatrics. 117:117-121, Ibanez L, et al. 2003 Clin Endocrinol. 58:372-379, Ibanez L, Potau N, de Zegher F. 1999 Pediatr Res. 46: 320-322 and Ibanez L, et al. 2000 Horm Res. 54:192-197; Ibanez L, et al. 2004 J Clin Endocrinol Metab. 89:4331-4337 and Ibanez L, et al. 2001 Clin Endocrinol. 55:667-672). Accordingly, insulin-sensitization with metformin is under exploration as an approach not only to prevent post-menarcheal progression to PCOS (Ibanez L, et al. 2000 J Clin Endocrinol Metab. 85:3526-3530; Ibanez L, et al. 2001 J Clin Endocrinol Metab. 86:3595-3598 and Ibanez L, et al. 2004 J Pediatr. 144:23-29), but also to prevent earlier steps within this sequence. In prepubertal LBW-PP girls, metformin treatment is known to induce within 6 mo a less adipose body composition, an

attenuated adrenarche, a more favourable lipid profile and a less pro-inflammatory state, as judged by normalization of the adipocytokine pattern and by a decrease in the neutrophil count (Ibanez L, et al. 2004 J Clin Endocrinol Metab. 89:4331-4337, Ibanez L, et al. 2005 J Clin Endocrinol Metab 90:3435-3439). The efficacy of metformin treatment in LBW-PP girls is herewith extended to include a less advanced onset of puberty and menses, while height gain is maintained.

C. ILLUSTRATIVE EMBODIMENTS OF THE INVENTION

An embodiment of present invention is the prevention or treatment of rapidly progressive puberty or early menarche by at least one insulin sensitizer or the use of at least one insulin sensitizer to manufacture a medicament for the prevention or treatment of rapidly progressive puberty or early menarche in female mammals.

Yet another embodiment of present invention is monotherapy by at least one insulin sensitizer to induce a slowdown in the tempo of pubertal progression or to prolong the duration of puberty.

Various insulin-sensitizing agents are available which can be used for the embodiments of the present invention. Suitable insulin-sensitizing agents for the application of present invention are for instance the insulin-sensitizing agents disclosed by Murakami et al, "A Novel Insulin Sensitizer Acts as a Coligand for Peroxisome Proliferation-Activated Receptor Alpha (PPAR alpha) and PPAR gamma. Other suitable insulin sensitizes include for instance the following agents: rosiglitazone; pioglitazone; MCC- 555; GL-262570, englitazone; darglitazone; isaglitazone; JTT-501; L- S95645; R-119702; NN-2344; and YM-440; insulin sensitizer, such as a biguanide or a thiazolidinedione; compounds selected from group of biguanides and thiazolidinediones, and in some cases, a combination of a biguanide and a thiazolidinedione, 2-ethoxy-l-[[2'- (5-oxo-2,5-dihydro- 1,2,4- oxadiazol-3-yl)biphenyl-4-yl]methyl]-lH- benzimidazole-7-carboxylic acid or a salt thereof; the insulin sensitizers (e.g., pioglitazone hydrochloride, troglitazone, rosiglitazone, GI-262570, JTT- 501, MCC-555, YM-440, KRP- 297, CS-OI l, FK-614 etc.), α-glucosidase inhibitors (e.g., voglibose, acarbose, miglitol, emiglitate etc.), biguanides (e.g., phenformin, metformin, buformin etc.); the thiazolidinedione insulin

sensitizer 5-[4-[2-(5- ethylpyridin-2-yl)ethoxy] benzyl] thiazolidine-2,4-dione (or pioglitazone); a thiazolidinedione insulin sensitizer more particularly a thiazolidinedione selected from the group consisting of BRL 49653, troglitazone, pioglitazone, ciglitazone, WAY-120,744, englitazone, AD 5075, Gl-262570, SB219994, SB219993, and darglitazone; insulin sensitizer which is a PPARγ agonist and more particularly a PPARγ agonist selected from the group consisting of BRL 49653, troglitazone, pioglitazone, ciglitazone, WAY-120,744, englitazone, AD 5075, darglitazone, Gl-262570, SB 217092, SB 236636, SB 217092, SB 219994, and SB 219993; an insulin sensitizer which is a RXR ligand and more particularly a RXR ligand selected from the group consisting of 9-cis retinoic acid, LG 100268 and LG 1069; an insulin sensitizer selected from the group consisting of an angiotensin converting enzyme inhibitor, a renin inhibitor, and an angiotensin antagonist; a non- thiazolidinedione insulin sensitisers include the compounds of formula (I) of International application, publication number WO 97/31907 or a pharmaceutically acceptable derivative thereof. A particular compound of WO 97/31907 (or EP0888317) is 2(S)-(2 -benzoyl- phenylamino)-3-{4-[2-5-methyl~2-phenyl-oxazol-4-yl)- ethoxy]- phenyl}- propionic acid or a pharmaceutically acceptable derivative thereof, such as a pharmaceutically acceptable salt or pharmaceutically acceptable solvate thereof and the thiazolidinedione insulin sensitizer 5-[4-[2-(5- ethylpyridin-2-yl)ethoxy] benzyl] thiazolidine-2,4-dione (or pioglitazone). Methods of preparation and formulation of these compounds are known in the art.

In a particular embodiment of present invention the insulin sensitizer is, for the application of present invention, combined with an insulin secretagogue. A suitable agent to be combined with insulin sensitizer is for instance a compound selected from the group consisting of biguanides, sulfonyl ureas, PTP-IB inhibitors, aldose reductase inhibitors, glucosidase inhibitors, PPAR γ agonists, PPAR a agonists, PPAR δ antagonists or agonists, aP2 inhibitors, PPAR aly dual agonists, dipeptidyl peptidase IV (DP4) inhibitors, SGLT2 inhibitors, glycogen phosphorylase inhibitors, and/or meglitinides, insulin, slow release insulin-Basulin®, and/or glucagon-like peptide- 1 (GLP-I) or a mimetics thereof.

m yet another embodiment of present invention the insulin sensitizer in the application of present invention is combined with at least one insulinotropic agent. Insulinotropic

agents include peptides such as incretins, which promote insulin secretion and beta cell development.

Incretins include glucagon-like peptide-1 (GLP-I) (P01275 GL45644939 residues 7 to 36 or 37), glucose-dependent insulinotropic polypeptide (GIP) (P09681 GI:121194 residues 52 to 93) and derivatives or agonists of these peptides, including exendin 3 (P20394 GI: 119677), exendin 4 (AAB22006.1 GI:248418)(Xu G et al 1999; Tourrel et al 2001) and NN2211 (Rolin B et al 2002). Insulinotropic peptides may be synthesized by conventional means as detailed below, such as solid-phase peptide synthesis. Solid phase peptide synthesis is described in J. M. Stewart and J. D. Young, Solid Phase Peptide Synthesis, W. H. Freeman Co. (San Francisco), 1963 and J. Meienhofer, Hormonal Proteins and Peptides, vol. 2, p. 46, Academic Press (New York), 1973. Insulinotropic peptides may also be produced through the use of recombinant DNA technology (for example, see Sambrook "Molecular Cloning, A Laboratory Manual, Cold Spring Harbor Laboratory Press 3rd Edition (2001), and Ausubel et al., Current Protocols in Molecular Biology, John Wiley and Sons, (1994)).

In a preferred embodiment the insulin sensitizer to delay the duration of puberty, to prevent or treat rapid puberty or to prevent early menarche is metformin (Registry Number: 657-24-9) and more particular a compound of the structure formula

or pharmaceutically acceptable salts, solvates or polymorphs thereof such as the polymorphs known in the art (Childs, S. L. and G.P. Stalily. 2004 Crystal Growth and Design 4 (May):441-449).

Metformin is the generic name of an oral antihyperglycemic drug used in the management of non-insulin-dependent diabetes mellitus (NIDDM) and having the chemical name N ₅ N-dimethylimidodicarbonimidic diamide hydrochloride. Metformin is e. g. known under trade names such as Glucophage or Dianben. Metformin has also been described by the CA Index Names as Imidodicarbonimidic diamide, N,N-

dimethyl- (9CI) or by other names such as Biguanide, 1,1 -dimethyl- (6CI ₅ SCI); 1,1- Dimethylbiguanide; DMGG; Dimethylbiguanide; Fluamine; Flumamine; Gliguanid; Haurymelin; Melbin; Metfoπnin; Metiguanide; Metphage; N'- Dimethylguanylguanidine; N,N-Dimethylbiguanide; N,N-Dimethyldiguanide; Nl ₅ Nl- Dimethylbiguanide; NNDG; Siofor. For the description of present invention and the ease of understanding it has been referred to as "Metformin".

Metformin or other insulin sensitizers may be administered in the form of one of its pharmaceutically acceptable salts, such as the hydrochloride, acetate, benzoate, citrate, fumarate, embonate, chlorophenoxyacetate, glycolate, palmoate, aspartate, methanesulfonate, maleate, para- chlorophenoxyisobutyrate, formate, lactate, succinate, sulfate, tartrate, cyclohexanecarboxylate, hexanoate, octanoate, decanoate, hexadecanoate, octadecanoate, benzenesulfonate, trimethoxybenzoate, para- toluenesulfonate, adamantanecarboxylate, glyoxylate, glutamate, pyrrolidonecarboxylate, naphthalenesulfonate, glucose- 1 -phosphate, nitrate, sulfite, dithionate, phosphate, dobesilate, thioctate, hippurate, 3-benzamidopropanoate, glucuronate, L-pyrroli-done- 5-carboxylate, cholate, α-glucose-1 -phosphate, alginate or 4-aminobenzoate, and the salt with chondroitinsulfuric acid. A particularly suitable pharmaceutically acceptable form of metformin is an acid addition salt, such as a hydrochloride.

Among these salts, the hydrochloride, fumarate, embonate and chlorophenoxyacetate are more particularly preferred.

The pharmaceutically acceptable salts of metformin are obtained, in a manner that is known per se, by the action of metformin or the corresponding acid.

The compositions of the invention comprise therapeutically effective amounts of the various active principles. The ratios of the respective amounts of metformin thus vary in consequence.

Of particular interest for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded

animal according to present invention are the thiazolidinediones (e.g. U.S. Pat Nos. 5,089,514, 4,342,771, 4,367,234, 4, 340,605, 5,306,726) and more particular ACTOS (pioglitazone hydrochloride), Pioglitazone [(±)-5-[[4-[2-(5-ethyl-2- pyridinyl)ethoxy]phenyl]methyl]-2,4-] thiazolidine-dione monohydrochloride with the structural formula is as shown:

or other functional dervatives thereof which are a member of the drug class of the thiazolidinedionesas such as described in Fujita et al., Diabetes, 32, 804-810, 19S3, JP- A S55(1980)-22636 (EP-A S203), JP-A S61(1986)-267580 (EP-A 193256) and being a selective agonist for the peroxisome proliferator-activated receptor- gamma (PP ARγ) or having mechanism of action of activating the intracellular receptor class of the peroxisome proliferator-activated receptors (PPARs), specifically PPAR7. Pioglitazone may be a standalone preparation and in combination with metformin or in combination with glimepiride.

US Patent 5,002,953 describes a class of thiazolidinedione derivatives for use as insulin sensitisers. One preferred compound described therein is known by the generic name rosiglitazone. Salts of this compound including the maleate salt are described in W094/05659. Certain pharmaceutical compositions are described in WO98/55122. Rosiglitazone is of particular interest for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal according to present invention is also rosiglitazone, 5-((4-(2- (methyl-2-pyridinylamino) ethoxy)phenyl)methyl)- 2,4-thiazolidinedione, with the structural formula is as shown

or other functional dervatives thereof which are a member of the drug class of the thiazolidinedionesas and being a selective agonist for the peroxisome proliferator- activated receptor- gamma (PP ARγ) or having mechanism of action of activation of the intracellular receptor class of the peroxisome proliferator-activated receptors (PPARs), specifically PP ARγ. Rosiglitazone is a pure ligand of PP ARγ, and has no PP ARa- binding action, for instance rosiglitazone maleate, (±)-5-[[4-[2- (methyl-2- pyridinylamino) ethoxy] phenyl]methyl] -2,4-thiazolidinedione, (Z)-2-butenedioate. Rosiglitazone may be a stand alone preparation and in combination with metformin or in combination with glimepiride.

Another insulin sensitizer of particular interest for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal according to present invention is the PP ARγ agonist CLX-0921 with a he structural formula is as shown:

In an other embodiment of present invention a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal comprises the insulin sensitizer, tesaglitazar (GALIDA), with the structure

and Oxeglitazar with the structure

Of particular interest for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal according to present invention is insulin sensitizer, BLX- 1002, which parallels with metformin, rosiglitazone, and pioglitazone, or derivatives thereof selected of the group consisting of (S)-2=Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5-ylidenemethyl)- phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3- {4-[4-(2,4-dioxo-thiazolidin-5-ymαethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt , (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5-ylidenemethyl)- 3- fluoro-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt , (S)-2- Amino-3-{4-[2-chloro-4-(2,4-dioxo-thiazolidin-5-ylidenemethy l)-phenoxy]-phenyl}- propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo- thiazolidin-5-ylidenemethyl)-2-methoxy-phenoxy]-ρhenyl}-ρr opionic^ acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5-ylidenemethyl)- 2-

nitro-phenoxyj-phenyl} -propionic acid methyl ester hydrochloric acid salt. The insulin sensitizer may be selected of the group consisting of (S)-2-Amino-3-{4-[4-(2,4-dioxo- thiazolidin-5-ylideneniethyl)-3-trifluoromethyl-phenoxy]-phe nyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5- ylidenemethyl)-phenoxy] -phenyl} -propionic acid , (S)-2-Amino-3-{4-[4-(2,4-dioxo- thiazolidin-5-ylidenemethyl)-phenoxy]-phenyl} -propionate dipotassium salt, (S)-2- Amino-3- {4-[4-(2,4-dioxo-tliiazolidin-5-ylidenemethyl)-phenoxy] -phenyl} -propionate disodium salt, (S)-2-Amino-3- {4-[3-chloro-4-(2,4-dioxo-thiazolidin-5-yhnethyl)- phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3- {4-[2-chloro-4-(2,4-dioxo-tliiazolidin-5-ybnethyl)-phenoxy]- phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5- ylmethyl)-2-methoxy-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin-5-ylmethyl)-2-flu oro-phenoxy]- phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4- dioxo-thiazolidin-5-ylmethyl)-phenoxy]-phenyl} -propionic acid hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(2,4-dioxo-tliiazolidin-5-ylmethyl)-phen oxy]-phenyl}-propionate disodium salt, (S)-2-Amino-3- {4-[4-(2,4-dioxo-tliiazolidin-5-yhnethyl)-phenoxy]- phenyl} -propionate dipotassium salt and (S)-2-Amino-3-{4-[4-(2,4-dioxo-thiazolidin- 5-ylmethyl)-phenoxy]-phenyl}-N,N-dimethyl-propionamide hydrochloric acid salt. The insulin sensitizer selected of the group consisting of (R,S)-2-Amino-3-{4-[4-(4-oxo-2- thioxo-thiazolidin-5-ylidenemethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[3-fluoro-4-(4-oxo-2-thioxo-thiazolidin-5- ylidenemethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[2-fluoro-4-(4-oxo-2-thioxo-thiazolidin-5-y lidenemethyl)-phenoxy]- phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[3- chloro-4-(4-oxo-2-thioxo-thiazolidin-5-ylidenemethyl)-phenox y]-phenyl}-propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[2-chloro-4-(4-oxo-2- thioxo-thiazolidin-5-ylidenemethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[2-methoxy-4-(4-oxo-2-thioxo-tliiazolidin-5 - ylidenemethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3- {4-[4-(4-oxo-2-thioxo-thiazolidin-5 -ylidenemethyD-phenoxy] -phenyl} - propionic acid methyl ester, (S)-2-Amino-3-{4-[4-(4-oxo-2-thioxo-thiazolidin-5- ylidenemethyl)-2-trifluoromethyl-phenoxy] -phenyl} -propionic acid methyl ester

hydrochloric acid salt and (S)-2-Amino-3-{4-[4-(4-oxo-2-thioxo-thiazolidin-5- ylidenemethyl)-3-trifluoiOmethyl-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt. The insulin sensitizer selected of the group consisting of (S)-2- Amino-3-{4-[2-methoxy-4-(4-oxo-2-thioxo-thiazolidin-5-yhτie thyl)-phenoxy]-phenyl}- propionic acid methyl ester hydrochloric acid salt, (R,S)-2-Amino-3-{4-[4-(4-oxo-2- tliioxo-thiazolidin-5-yhnethyl)-phenoxy]-phenyl} -propionic acid methyl ester, (S)-2- Amino-3-{4-[2-chloro-4-(4-oxo-2-thioxo-tliiazolidin-5-yhneth yl)-phenoxy]-phenyl}- propionic acid methyl ester hydrochloric acid salt, (S)-2-Arnino-3-{4-[3-chloro-4-(4- oxo-2-thioxo-thiazolidin-5-yhnethyl)-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[3-fluoro-4-(4-oxo-2-thioxo-thiazolidin-5- ylmethyl)-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2- Amino-3-{4-[2-fluoro-4-(4-oxo-2-tliioxo-thiazolidin-5-ylmeth yl)-phenoxy]-phenyl}- propionic acid methyl ester hydrochloric acid salt and (S)-2-Amino-3-{4-[4-(4-oxo-2- thioxo-thiazolidin-5-yhnethyl)-3-trifluoromethyl-phenoxy]-ph enyl}-propionic acid methyl ester hydrochloric acid salt. The insulin sensitizer selected of the group consisting of (R,S)-2-Amino-3- {4-[4-(3-carboxymethyl-4-oxo-2-thioxo-thiazolidin-5- ylidenemethyl)-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(3-carboxymethyl-4-oxo-2-thioxo-thiazoli din-5-ylidenemethyl)-3- chloro-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2- Amino-3-{4-[4-(3-cai'boxymethyl-4-oxo-2-thioxo-thiazolidin-5 -ylidenemethylV2- chloro-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2- Amino-3-{4-[4-(3-carboxymethyl-4-oxo-2-thioxo-thiazolidm-5-y lidenemethyl)-2- fluoro-phenoxy]-phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2- Amino-3-{4-[4-(3-carboxymethyl-4-oxo-2-tliioxo-thiazolidin-5 -ylidenemethyl)-2- trifluoromethyl-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2-Amino-3-{4-[4-(3-carboxymethyl-4-oxo-2-thioxo-thiazoli din-5-ylidenemethyl)-3- fluoro-phenoxy] -phenyl} -propionic acid methyl ester hydrochloric acid salt, (S)-2- Amino-3-{4-[4-(3-cai'boxymethyl-4-oxo-2-tliioxo-thiazolidin- 5-ylidenemethyl)-3- tiifluoromethyl-phenoxyj-phenyl} -propionic acid methyl ester hydrochloric acid salt and (S)-2-Amino-3- {4-[4-(3-carboxymethyl-4-oxo-2-thioxo-tbiazolidin-5- ylidenemethyl)-2-methoxy-phenoxy]-phenyl}-propionic acid methyl ester hydrochloric acid salt. The insulin sensitizer selected of the group consisting of (RS)-2-Amino-3-{4- [4-(3-carboxymethyl-4-oxo-2-thioxo-thiazolidin-5-yhnethyl)-p henoxy]-phenyl}-

propionic acid methyl ester hydrochloric acid salt and (S)-2-Amino-3-{4-[4-(3- carboxymethyl-4-oxo-2-thioxo-thiazolidin-5-yhnethyl)-phenoxy ]-phenyl}-propionic acid methyl ester hydrochloric acid salt and (S)-2-Amino-3-{4-[4-(3-carboxymethyl-4- oxo-2-thioxo-thiazolidin-5-ylmethyl)-3-trifluoromethyl-pheno xy]-phenyl}-propionic acid methyl ester hydrochloric acid salt. The insulin sensitizer selected of the group consisting of 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)benzilidene]thiazoli din-2,4- dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)ρhenoxy)benzilidene]thiazolidin-2,4-di one or its salts; 5-[4-(4- (2-Amino-2-carboxyethyl)phenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarboiiylethyl)phenoxy)benzyl]thiazolidin-2,4 -dione or its salts; 5-[4- (4-(2-Amino-2-carboxyethyl)phenoxy)benzilidene]oxazolidin-2, 4-dione or its salts; 5- [4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)benzilidene]ox azolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)benzyl]oxazolidin-2, 4-dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)benzyl]oxazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,6- difluorobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-2,6-difluoiObenzilidene]oxazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,6-difluorobenzyl] oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-2,6- difluorobenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-2,6-difluorobenzilidene]thiazolidin-2, 4-dione or its salts; 5-[4- (4-(2-Arnino-2-methoxycarbonylethyl)phenoxy)-2,6-difluoroben zilidene]thiazolidin- 2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,6- difluorobenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-2,6-difluorobenzyl]thiazolidin -2,4-dione or its salts; 5- [4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,3-difluorobenzilide ne]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-2,3- difluorobenzilidene]thiazolidin-2 _J 4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-2,3-difluorobenzyl]tliiazolidin-2,4-di one or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-2,3-difluorobenzyl]thi azolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,3- difluorobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-2,3-difiuorobenzilidene]oxazol idin-2,4-dione or its

salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2,3-difluorobenzyl] oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-2,3- difluorobenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-methylbenzilidene]oxazolidin-2 ₅ 4-dione or its salts; 5-[4-(4- (2-Amino-2-methoxycarbonylethyl)phenoxy)-3-methylbenzilidene ]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3- methylbenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-3-methylbenzyl]oxazolidin-2,4- dione or its salts; 5-[4- (4-(2-Amino-2-carboxyethyl)phenoxy)-3-metliylbenzilidene]thi azolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)ρhenoxy)-3- methylbenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-methylbenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonyletb.yl)phenoxy)-3-methylbenzyl]thiazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-nitrobenzilidene] thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- nitrobenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-nitrobenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycai"bonylethyl)phenoxy)-3-nitrobenzyl]thiazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-nitrobenzilidene] oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- nitrobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-nitrobenzyl]oxazolidiii-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-3-nitrobenz)4]oxazolid in-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-aminobenzilidene] thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- aminobenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-aminobenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-3-aminobeiizyl]tliiazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-aminobenzilidene] oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- aminobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-aminobenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-3-aminobenzyl]oxazolid in-2,4-dione or its

salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2-fluorobenzilidene ]thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-2- fluorobenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-2-fluorobenzyl]thiazolidm-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-2-fluoroberLzyl]thiazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2-fluorobenzilidene ]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-2- fluorobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-2-fluorobenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycai"bonylethyl)phenoxy)-2-fluorobenzyl]oxazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-fluorobenzilidene ]thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- fluorobenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Arnino-2- carboxyethyl)phenoxy)-3-fluorobenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-3-fluorobenzyl]thiazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-fluorobenzilidene ]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)phenoxy)-3- fluorobenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)phenoxy)-3-fluorobenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)phenoxy)-3-fluorobenzyl]oxazoli din-2,4-dione or its salts; 5-[4-(4-(2-Ammo-2-carboxyethyl)phenoxy)-2- trifluoromethylbenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-2-trifluoiOmethylbenzilidene]t hiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Aniino-2-carboxyethyl)phenoxy)-2- trifluoromethylbenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)ρhenoxy)-2-trifluoromethylbenzyl]thiaz olidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2carboxyethyl)phenoxy)-2- trifluoromethylbeiizilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycai-bonylethyl)phβnoxy)-2-trifluoromethylbenzilidene ]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-2- trifluoromethylbenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- niethoxycarbonylethyl)phenoxy)-2-trifluoromethylbenzyl]oxazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3-

trifluoroniethylbenzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Arnino2- methoxycarbonylethyl)phenoxy)-3-trifluoromethylbenzilidene]t hiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3- trifluoromethylbenzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-3-trifluorometliylbenzyl]thiaz olidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3- trifluororaethylbenzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Aniino-2- methoxycarbonylethyl)phenoxy)-3-trifluoromethylbenzilidene]o xazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)phenoxy)-3- trifluorornethylbenzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)phenoxy)-3-trifluoromethylbenzyl]oxazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2 _; ,6-diiluorophenoxy)benzilidene]oxazolidin- 2,4-dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-2,6- difluorophenoxy)benzilidene]oxazolidin-2,4-dione or its salts 5-[4-(4-(2-Aniino-2- carboxyethyl)-2,6-difluorophenoxy)benzyl]oxazolidin-2,4-dion e or its salts; 5-[4-(4-(2- Amino-2-methox)'carbonylethyl)-2,6-difluorophenoxy)benzyl]ox azolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2,6- difluorophenoxy)beiizilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Aniino-2- methoxycarbonyleth.yl)-2,6-difluorophenoxy)benzilidene]thiaz olidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2,6-difluorophenoxy)benzyl] thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-niethoxycarbonyletb.yl)-2,6- difluorophenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-2,3-difluorophenoxy)benzilidene]thiazolidin-2, 4-dione or its salts 5-[4- (4-(2-Arnino-2-methoxycarbonylethyl)-2,3-difluorophenoxy)ben zilidene]thiazolidin- 2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2,3- difluorophenoxy)benzyl]tbiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Aniino-2- methoxycarbonylethyl)-2,3-difluorophenoxy)benzyl]thiazolidin -2,4-dione or its salts; 5- [4-(4-(2-Amino-2-carboxyethyl)-2,3-di£luorophenoxy)benzilid ene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-2,3- difluorophenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Aniino-2- carboxyethyl)-2,3-difluorophenoxy)benzyl]oxazolidin-2,4-dion e or its salts; 5-[4-(4-(2- Aniino-2-niethoxycarbonylethyl)-2,3-difluorophenoxy)beii2yl] oxazolidin-2 _J 4-dione or its salts; 5-[4-(4-(2-Aniino-2-carboxyethyl)-3-methylphenoxy)benziliden e]oxazolidin-

2,4-dione or its salts; 5-[4-(4-(2~Amino-2-methoxycarbonylethyl)-3- methylphenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-methylphenoxy)ben2yl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Ainino-2-methoxycarbonylethyl)-3-methylphenoxy)benzyl]oxazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-methylphenoxy)ben2;iliden e]thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- methylphenoxy)benzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-methylρhenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonyletb.yl)-3-methylphenoxy)benzyl]thiazo lidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-nitrophenoxy)benzilidene] tbiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- nitrophenoxy)benzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-nitrophenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3 -nitiOphenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-nitτophenoxy)benzilidene ]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- nitrophenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-nitiOphenoxy)benzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3-nitrophenoxy)benzyl]oxazolid in-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-aminophenoxy)benzilidene] thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- arninophenoxy)benzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-aminophenoxy)benzyl]tliiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3-aminophenoxy)benzyl]thiazoli din-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-aminophenoxy)benzilidene] oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- aminophenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-aminophenoxy)benzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3 -aminopb.enoxy)benzyl] oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2-fluoiOphenoxy)benzilidene ]tliiazolidin-2 ₅ 4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-2- fluorophenoxy)benzilidene]thiazolidin-2 _: ,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-2-fluorophenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-

Amino-2-methoxycarbonylethyl)-2-fluorophenoxy)benzyl]thiazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2-fluoiOphenoxy)beiiziliden e]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-2- fluorophenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-2-fluorophenoxy)benzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-2-fluorophenoxy)benzyl]oxazoli din-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-fluorophenoxy)benzilidene ]thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- fluorophenoxy)benzilidene]tliiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-fluorophenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3-fluoiOphenoxy)benzyl]thiazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3-fluorophenoxy)benzilidene ]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-methoxycarbonylethyl)-3- fluorophenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- carboxyethyl)-3-fluorophenoxy)benzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-3-fluorophenoxy)benzyl]oxazoli din-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2- trifluoromethylphenoxy)benzilidene]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Aniino-2-methoxycarbonylethyl)-2-trifluoromethylphenoxy)beii zilidene]tlτiazolidin- 2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2- trifluoromethylphenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)-2-trifluoromethylphenoxy)benzyl]thiazo lidin-2 _: ,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2- trifluoromethylphenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonylethyl)-2-trifluoromethylphenoxy)benzi lidene]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-2- trifluoromethylphenoxy)benzyl]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2- methoxycarbonylethyl)-2-trifluoromethylphenoxy)benzyl]oxazol idin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3- trifluoromethylphenoxy)benzilidene]tliiazolidin-2,4-dione or its salts; 5-[4-(4-(2- Amino-2-methoxycarbonyletb.yl)-3-trifluoroniethylphenoxy)ben zilidene]thiazolidin- 2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3- trifluoromethylphenoxy)benzyl]thiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-

methoxycarbonylethyl)-3 -trifluoromethylphenoxy)benzyl]tliiazolidin-2,4-dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyl)-3- txifluoromethylphenoxy)benzilidene]oxazolidin-2,4-dione or its salts; 5-[4-(4-(2- Ai-nino-2-methoxycarbonylethyl)-3-trifluoromethylphenoxy)bei izilidene]oxazolidin-2,4- dione or its salts; 5-[4-(4-(2-Amino-2-carboxyethyi)-3- trifluoromethylphenoxy)benzyl]oxazolidin-2 ₅ 4-dione or its salts; 5-[4-(4-(2-Amino-2- metb.oxycarbonylethyl)-3-tri£luoromethylprienoxy)benzyl]oxa zolidin-2,4-dione or its salts; 5-[4-(4~(2-t-butoxycarbonylamino-2- methoxycarbonylethyl)phenoxy)benzilidene]thiazolidin-2,4-dio ne or its salts; 5-[4-(4- (2-t-butoxycarbonylaniino-2-methoxycarbonylethyl)phenoxy)ben zyl]thiazolidin-2,4- dione or its salts; 5-[4-(4-(2-t-butoxycarbonylamino-2- methoxycarbonylethyl)phenoxy)benzilidene]oxazolidin-2,4-dion e or its salts; 5-[4-(4- (2-t-butoxycarbonylamino-2-methoxycarbonylethyl)phenoxy)benz yl]oxazolidin-2,4- dione or its salts. 5-[4-(4-(2-t-butoxycarbonylamino-2- carboxyethyl)phenoxy)benzilidene]thiazolidin-2,4-dione or its salts; and 5-[4-(4-(2-t- butoxycarbonylamino-2-carboxyethyl)phenoxy)beiizyl]tliiazoli din-2,4-dione or its salts; and 5-[4-(4-(2-t-butoxycarbonylamino-2-carboxyethyl)phenoxy)benz ilidene]oxazolidin- 2,4-dione or its salts and 5-[4-(4-(2-t-butoxycarbonylamino-2- carboxyethyl)phenoxy)benzyl]oxazolidin-2,4-dione or its salts.

BLX-1002, insulin sensitizer which parallels with metformin, rosiglitazone, and pioglitazone, or derivatives thereof can be of the general formule:

its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates, wherein represents an optional

double bond; Y represents oxygen, sulfur or NR, wherein R represents hydrogen or alkyl,; Z represents oxygen or sulfur, Ri, R ₂ , R ₃ and R ₄ may be same or different and independently represent hydrogen, halogen, hydroxy, nitro, cyano, formyl, amino, alkyl, or alkoxy, A represents a bond or subsituted or unsubstituted aryl, heterocyclyl or heteroaryl ring; X represents an alpha amino carboxylic acid or aplha amino carboxylic acid derivative bonded to A or Y through its aplha side chain.

Also halofenate insulin sensitiser more particularly a "(-)2-acetamidoethyl 4- chlorophenyl-(3-trifluoromethylphenoxy)-acetate" or "(-) halofenate." such as Metaglidasen ((-) (3-trihalomethylphenoxy) (4-halophenyl) acetic) or functionally active derivatives that are selective peroxisome proliferator-activated receptor (PPAR) modulators can also be suitable for the preparation of a composition of a treatment to delay the onset of puberty or to slow down the tempo of pubertal progression in a warm-blooded animal

The compositions of the invention are preferably administered parenterally or better still orally, although the other routes of administration, such as, for example, rectal administration, are not excluded.

If oral administration is envisaged, the compositions of the invention are in the form of gel capsules, effervescent tablets, coated or uncoated tablets, sachets, sugar-coated tablets, drinkable vials or solutions, microgranules or sustained-release forms.

If parenteral administration is envisaged, the compositions of the invention are in the form of injectable solutions and suspensions packaged in vials or bottles for slow venous infusion.

The forms for oral administration are prepared by mixing the active substance with various types of excipients or of vehicles, such as fillers, disintegration (or crumbling) agents, binders, colorants, flavour enhancers and the like, followed by shaping of the mixture.

The colorant can be any colorant permitted for pharmaceutical use.

Examples of flavour enhancers include cocoa powder, mint, borneol and cinnamon powder.

Examples of binders that may be mentioned are polyvinylpyrrolidone, hydroxypropyl- methylcellulose, alginic acid, carbomer, carboxymethylcellulose., dextrin, ethylcellulose, starch, sodium alginate, polymethacrylate, maltodextrin, liquid glucose, magnesium aluminium silicate, hydroxyethylcellulose, ethylcellulose, methylcellulose and guar gum.

It is possible to use alginic acid, sodium carboxymethylcellulose, colloidal silicon dioxide, sodium croscarmellose, crospovidone, guar gum, magnesium aluminium silicate, methylcellulose, microcrystalline cellulose, potassium polacrilin, cellulose powder, pre- gelatinised starch, sodium alginate or sodium starch glycolate as disintegration agent.

The fillers are, for example, cellulose, lactose, calcium hydrogen phosphate or microcrystalline cellulose.

The tablets can be obtained in a conventional manner by compressing granules in the presence of one or more lubricants. Suitable lubricants are calcium stearate, glyceryl monostearate, glyceryl palmitostearate, hydrogenated castor oil, hydrogenated plant oil, light mineral oil, magnesium stearate, polyethylene glycol, sodium benzoate, sodium lauryl sulfate, stearyl sodium fumarate, stearic acid, talc and zinc stearate. These tablets can then be coated using polymers in solution or suspension, such as hydroxypropyhnethylcellulose or ethylcellulose.

The granules used to do this are prepared, for example, by using the wet granulation process stalling with a mixture of the active principles with one or more excipients, such as a binder, a crumbling agent (or disintegration agent) and a filler.

To obtain hard capsules, the mixture of active principles with a suitable filler (for example lactose) is incorporated into empty gelatine capsules optionally in the presence of a lubricant, such as magnesium stearate, stearic acid, talc or zinc stearate.

Gel capsules or soft capsules are prepared by dissolving the active principles in a suitable solvent (for example polyethylene glycol), followed by incorporation into soft capsules.

The forms for parenteral administration are obtained in a conventional manner by mixing the active principles with buffers, stabilisers, preserving agents, solubilising agents, tonicity agents and suspension agents. In accordance with the known techniques, these mixtures are subsequently sterilised and then packaged in the form of intravenous injections.

As buffer, a person skilled in the art can use buffers based on organophosphate salts.

Examples of suspension agents include methylcellulose, hydroxyethylcellulose, acacia and sodium carboxymethylcellulose.

Examples of solubilising agents include castor oil solidified with polyoxyethylene, polysorbate 80, nicotinamide and macrogol.

In addition, stabilisers that are useful according to the invention are sodium sulphite and sodium metasulphite, while mention may be made of sodium p-hydroxybenzoate, sorbic acid, cresol and chlorocresol as preserving agents. For the preparation of an oral solution or suspension, the active principles are dissolved or suspended in a suitable vehicle with a dispersant, a wetting agent, a suspension agent (for example polyvinylpyrrolidone), a preserving agent (such as methylparaben or propylparaben), a flavour enhancer or a colorant.

For the preparation of suppositories, the active principles are mixed in a manner that is known per se with a suitable base constituent, such as polyethylene glycol or semisynthetic glycerides.

For the preparation of microcapsules, the active principles are combined with suitable diluents, suitable stabilisers, agents that promote the sustained release of the active substances or any other type of additive for the formation of a central core that is then coated with a suitable polymer (for example a water-soluble resin or a water-insoluble resin). The techniques known to those skilled in the art will be used for this purpose.

The microcapsules thus obtained are then optionally formulated in suitable dosage units.

In the method of the invention, the active medicaments are preferably administered in pharmaceutical composition form. As indicated above, such compositions can include both medicaments and one only of the medicaments.

The metformin or a pharmaceutically acceptable salt or polymorph thereof can be in the form of any of the salts defined above; however, it is preferred to use metformin in unmodified form or in the form of the hydrochloride, fumarate, embonate or chlorophenoxyacetate .

Usually the compositions comprising an insulin sensitizer are adapted for oral administration. However, they may be adapted for other modes of administration, for example parenteral administration, sublingual or transdermal administration.

The compositions may be in the form of tablets, capsules, powders, granules, lozenges, suppositories, reconstitutable powders, or liquid preparations, such as oral or sterile parenteral solutions or suspensions.

In order to obtain consistency of administration it is preferred that a composition of the invention is in the form of a unit dose.

Unit dose presentation forms for oral administration may be tablets and capsules and may contain conventional excipients such as binding agents, for example syrup, acacia, gelatine, sorbitol, tragacanth, or polyvinylpyrrolidone; fillers, for example lactose, sugar, maize- starch, calcium phosphate, sorbitol or glycine; tabletting lubricants, for

example magnesium stearate; disintegrants, for example starch, polyvinylpyrrolidone, sodium starch glycollate or microcrystalline cellulose; or pharmaceutically acceptable wetting agents such as sodium lauryl sulphate.

The compositions are preferably in a unit dosage form in an amount appropriate for the relevant daily dosage.

The composition of the invention may be administered from 1 to 6 times a day, but most preferably 1 or 2 times per day.

Suitable unit dosages of the insulin sensitizer or the biguanide antihyperglycaemic agent, such as metformin, include the known doses for these compounds as described or referred to in reference texts such as the British and US Pharmacopoeias, Remington's Pharmaceutical Sciences (Mack Publishing Co.), Martindale The Extra Pharmacopoeia (London, The Pharmaceutical Press) (for example see the 31st Edition page 341 and pages cited therein) or the above mentioned publications.

Suitable dosages of metformin include up to 3000 mg per day, in unit doses of 500 mg (for example two or three times per day) or 850 mg (for example two times per day), one example of a dosage for metformin is 500 mg once per day, building up to five times per day.

Metformin or its pharmaceutically acceptable salt can be incorporated into pharmaceutical at an unit dose from 50 to 1000 mg of metformin. In general, the daily dosage ranges between 100 and 2000 mg of metformin.

Thus, one example of the method comprises the administration of 1000 mg or 2500 mg of metformin (at 500 mg twice per day or 500 mg five times per day respectively).

Naturally, the dosage depends on the method of administration, the therapeutic indication, and the age and condition of the patient.

The solid oral compositions may be prepared by conventional methods of blending, filling or tabletting. Repeated blending operations may be used to distribute the active agent throughout those compositions employing large quantities of fillers. Such operations are of course conventional in the art. The tablets may be coated according to methods well known in normal pharmaceutical practice, in particular with an enteric coating.

Oral liquid preparations may be in the form of, for example, emulsions, syrups, or elixirs, or may be presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, for example sorbitol, syrup, methyl cellulose, gelatine, hydroxyethylcellulose, carboxymethyl-cellulose, aluminium stearate gel, hydrogenated edible fats; emulsifying agents, for example lecithin, sorbitan monooleate, or acacia; non-aqueous vehicles (which may include edible oils), for example almond oil, fractionated coconut oil, oily esters such as esters of glycerine, propylene glycol, or ethyl alcohol; preservatives, for example methyl or propyl p-hydroxybenzoate or sorbic acid; and if desired conventional flavouring or colouring agents.

For parenteral administration, fluid unit dosage forms are prepared utilizing the compound and a sterile vehicle, and, depending on the concentration used, can be either suspended or dissolved in the vehicle. In preparing solutions the compound can be dissolved in water for injection and filter sterilized before filling into a suitable vial or ampoule and sealing. Advantageously, adjuvants such as a local anaesthetic, a preservative and buffering agents can be dissolved in the vehicle. To enhance the stability, the composition can be frozen after filling into the vial and the water removed under vacuum. Parenteral suspensions are prepared in substantially the same manner, except that for the compounds which are suspended in the vehicle instead of being dissolved, and sterilization cannot be accomplished by filtration. The compound can be sterilized by exposure to ethylene oxide before suspending in the sterile vehicle. Advantageously, a surfactant or wetting agent is included in the composition to facilitate uniform distribution of the compound.

Compositions may contain from 0.1% to 99% by weight, preferably from 10-60% by weight, of the active material, depending upon the method of administration.

Compositions may, if desired, be in the form of a pack accompanied by written or printed instructions for use. The use of the composition to slow down the tempo of pubertal progression or to delay menarche may be specifically mentioned in these instructions for use.

The compositions are formulated according to conventional methods, such as those disclosed in standard reference texts, for example the British and US Pharmacopoeias, Remington's Pharmaceutical Sciences (Mack Publishing Co.), Martindale The Extra Pharmacopoeia (London, The Pharmaceutical Press) (for example see the 31st Edition page 341 and pages cited therein) and Harry's Cosmeticology (Leonard Hill Books).

In some embodiments, a compound of treatment is continuously administered to the female mammals or the human girls at risk of rapid puberty or early menarche to monitor the tempo of pubertal progression. Continuous administration may be especially suitable for short-acting agents sensitizers or accompanying active agents such as insulin-secretagogue or insulinotropic agents. Methods and means of continuous administration of therapeutic agents are well known in the art. For instance, solid implant drug delivery systems containing a drug incorporated in thermoplastic or thermosetting biodegradable polymers have been widely used. Such implants have to be inserted into the body through an incision which is sometimes larger than that desired by the medical professional and occasionally lead to a reluctance of the patients to accept such an implant or drug delivery system. The following U.S. Pat. Nos. 6,113,624; 5,868,788; 5,714,551; 5,713,920; 5,639,851; 5, 468,253; 5,456,679; 5,336, 057; 5,308,348; 5,279,608; 5,234,693; 5,234, 692; 5,209,746; 5,151,093; 5, 137,727; 5,112,614; 5,085,866; 5,059,423; 5, 057,318; 4,865,845; 4,008,719; 3,987,790 and 3,797,492 are believed to be representative of such drug delivery systems and are incorporated herein by reference. These patents disclose reservoir devices, osmotic delivery devices and pulsatile delivery devices for delivering beneficial agents. Injecting drug delivery systems as small particles, microspheres, or microcapsules avoids the incision needed to implant drug delivery systems. The art has developed various drug

delivery systems in response to the aforementioned challenges. The following U.S. Pat. Nos. 6, 432,438; 5,990, 194; 5,780,044; 5,733,950; 5,620,700; 5,599,552; 5,556, 905 5,278,201; 5, 242,910 and 4,938,763; and PCT publications WO 98/27962; WO 02/00137 and WO 02/058670 are believed to be representative and are incorporated herein by reference. See also Jain, R. et al, " Controlled drug delivery by biodegradable poly(ester) devices: different preparative approaches," Drug Dev. Ind. Pharm., 24(8): 703- 727, 1998; Eliaz, R. E. and Kost, J., "Characterization of a polymeric PLGA- injectable implant( ^λ ) deliver system for the controlled release of proteins," J. Biomed. Master Res., 50(3): 388-396, 2000; and Jain, R. A., "The manufacturing techniques of various drug loaded biodegradable poly(lactide-co-glycolide) (PLGA) devices," Biomaterials, 21(23): 2475-90, 2000. These patents and publications disclose polymer compositions for injectable implants using solvents and/or plasticizers. It will be apparent to those skilled in the art that various modifications and variations can be made in the treatment or prevention of early menarche or rapid puberty using the insulin sensitizers of the present invention and in the construction of the system and method without departing from the scope or spirit of the invention. Examples of such modifications have been previously provided.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only.

Table 1. Clinical, endocrine-metabolic, ultrasonography and body composition indices in girls with low birthweight and early-normal puberty, who were randomized to remain untreated or to receive metformin (850 mg/d) for 36 months.

Abdominal Fat Mass (Kg) 3.7 ± 0.5 6. 4 ± 0.5 # Ut 4. 7 ± 0.6 4 ,9 ± 0 .5 Lean Body Mass (Kg) 25.2 ± 1.2 31. 8 + 1.1 ## Ut 26. 6 ± 1.0 36.0 ± 0.8

Bone Mineral Density (g/cm2) 0.8 ± 0.02 1.1 ± 0.03 0.8 > ± 0.03

1.1 ± 0.02

Uterine length (mm) 42 ± 2 66 ± 1 40 ± 1 66 + 2 Mean ovarian volume (imL) 2.9 ± 0.2 3. 3 + 0.1 3. .0 ± 0.2 3 ,7 ± 0 .1

Values are mean ± SEM; BMI: Body Mass Index; IGFBP-1 , insulin-like growth factor binding-protein-1

* after 24 mo ^t Values (mean + SEM) in healthy, Tanner-stage matched girls (references 20,26 & 28) are as follows: Total Fat Mass, B2: 9.2 ± 0.8 Kg; B5: 12.9 ± 1.1 Kg; Abdominal Fat Mass, B2: 1.6 + 0.2 Kg; B5: 3.0 ± 0.4 Kg; Lean Body Mass, B2: 23.2 ± 0.7 Kg; B5: 32.7 ± 0.7 Kg; HOMA, B2: 1.3 ± 0.1 ; B5: 1.5 + 0.1 ; Leptin, B2: 7.5 ± 0.9 ng/mL; B5: 10.3 ± 1.8 ng/mL

Untreated versus Treated :

# p<0.05; ## p<0.01 ; ### p<0.001 at 36 mo;

+. p<0.05; tt p<0.01 ; +.+-φ p<0.001 for changes (over 0-36 mo, unless indicated otherwise).

Table 2. Height and bone age in girls with low birthweight and early-normal puberty, who were randomized to remain untreated or to receive metformin (850 mg/d) for 36 months. Between 36-42 mo, all girls were untreated.

ηeight velocity between 36-42 months Untreated versus Treated : # p<0.05; ## pr.9.01

Table 3. Baseline characteristics of the study population.

Total (n=38) Untreated (n=19) Treated (n=19)

Birthweight (Kg) 2.4 + 0.1 2.5 ±0.1 2.4 ±0.1

Gestational age (wk) 38.6 ± 0.4 38.7 ± 0.6 38.5 + 0.5

Age at diagnosis of PP (yr) 6.8 ± 0.2 7.1 ±0.2 6.6 ± 0.3

Age at study start (yr) 7.9 ±0.1 8.0 + 0.2 7.9 ±0.2

Bone age (yr) 9.0 ±0.1 9.1 ±0.2 8.8 ± 0.2

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Height (cm) 129.4 ±1.2 130.0 ±1.9 128.9 ±1.6

Weight (Kg) 31.0 ±0.9 30.8 ±1.2 31.3 ±1.4

BMI (Kg/m ² ) 18.4 ±0.3 18.1 ±0.4 18.7 ±0.6

Adrenal androgens at PP diagnosis

DHEAS (μg/dL) 102 + 6 96 + 5 108 ±10

Post-ACTH 17-OHP (ng/dL) 274 ±16 281 ± 24 268 ± 20

Values are mean ± SEM.

BMI, body mass index; PP, precocious pubarche; DHEAS, dehydroepiandrosterone-sulfate; 17-OHP, 17-hydroxyprogesterone.

To convert units to Sl, multiply the concentrations of DHEAS by 0.02714 and those of 17-OHP by 0.03026.

Table 4. Clinical, endocrine-metabolic, and body composition indices in prepubertal girls (age ~ 8 y) with a combined history of low birth weight and precocious pubarche. Girls were randomized to remain untreated (n =19) or to receive treatment with metformin (425 mg/d; n=19) for 24 mo.

Values are mean ± SEM. SHBG, sex hormone-binding globulin; DHEAS, dehydroepiandrαsterone-sulfate; BMD, bone mineral density; BMC, bone mineral content. To convert units to Sl, multiply the concentrations of testosterone by 0.03467; those of androstenedione by 0.0349; those of DHEAS by 0.02714; divide the concentrations of SHBG by 0.0288; those of triglycerides by 88.5, and those of HDL-cholesteroi and LDL- cholesterol by 38.7. ^a non-symptomatic prepubertal girls matched for body size [n=24 for endocrine-metabolic variables, age 8.3 ± 0.3 y (reference 18); n=12 for iGFBP-1 and ieptin, age 8.2 ± 02 y, n=13 for body composition, age 8.4 ± 0.4 yj. ^b no significant differences between randomized subgroups at 0 mo ^c p < 0.05, ^d p < 0.01, ^e p < 0.001 vs reference ^f p < 0.05, ⁸ P < 0.01, ^h p < 0.001, 'p < 0.0001 vs baseline (0 mo)

¹ P < 0.05, ^k p < 0.01, 'p < 0.001 for 0-24 mo change (δ) vs untreated.

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