BACKGROUND OF THE INVENTION A"hot flush"is a sudden transient sensation ranging from warmth to intense heat and typically accompanied by flushing and perspiration. It is the classic sign of the menopause and the predominant complaint of menopausal women. Epidemiological studies report that the majority of menopausal women experience hot flushes, although with large variation in frequency and intensity (Treatment of the Postmenopausal Woman, Basic and Clinical Aspects, Raven Press 1994, ed. R. A. Lobo).

A positive correlation between plasma levels of calcitonin gene-related peptide (CGRP) and frequency of hot flushes in women has recently been reported (Chen et al., 1993, Lancet (342) 49), in accordance with the potent vasodilatory effect of CGRP (Brain et al., 1985, Nature, (313) 54-56).

Recently, a novel heptadeca peptide, nociceptin, was discovered (Meunier et al., 1995, Nature (377) 532-535, Reinscheid et al., 1995, Science (270) 792-794) Nociceptin and analogues thereof have been disclosed in WO 97/07212 and in WO 97/07208. These peptides and inhibitors thereof are said to be useful for antagonising physiologic effects of an opioid in an animal, and for treating/preventing a disease

related to: hyperalgesia, neuroendocrine secretion, stress, locomotor activity, anxiety etc.

SUMMARY OF THE INVENTION The present invention provides the use of a compound selected from nociceptin or an analogue, a variant or a homologue thereof, wherein 1 to 12 amino acid (s) have been deleted, 1-82 amino acid (s) have been added and/or 1-15 amino acid (s) have been substituted, or a pharmaceutically acceptable salt thereof, for the preparation of a pharmaceutical composition for the treatment of vasomotor disturbances, in particular the peripheral vasomotor effects known as hot flushes or hot flashes, wherein the deletion (s), addition (s) and/or substitution (s) does not substantially reduce the vasomotor disturbing effects of the analogue, variant or homologue of nociceptin.

It is an object of the invention to use a compound selected from nociceptin or an analogue, a variant or a homologue thereof, for the preparation of a pharmaceutical composition for a new use (new medical indication).

Further objects will become apparent from the following description.

DETAILED DESCRIPTION OF THE INVENTION It has been found that nociceptin and nociceptin analogues, variants or homologues inhibit cordal stimulated vasodilatation in the pithed rat (an in-vivo-model for the hot flushes, hereafter referred to as"the pithed rat") which is known to be mediated by CGRP (Nuki Y. et al. Effects of Dorsal Rhizotomy on Depressor Response to Spinal Cord Stimulation Mediated by Endogenous Calcitonin Gene-related Peptide in the Pithed Rat. J. Neurosurg. 1993; 79: 899-904).

Accordingly, in a first aspect, the present invention relates to the use of a compound selected from nociceptin or an analogue, a variant or a homologue thereof, wherein 1

to 12 amino acid (s) have been deleted, 1-82 amino acid (s) have been added and/or 1- 15 amino acid (s) have been substituted, or a pharmaceutically acceptable salt thereof, for the preparation of a pharmaceutical composition for the treatment of vasomotor disturbances, in particular the peripheral vasomotor effects known as hot flushes or hot flashes or for alleviating symptoms of drug withdrawal in particular abstinence symptoms occuring during withdrawal from abusive drugs, wherein the deletion (s), addition (s) and/or substitution (s) does not substantially reduce the vasomotor disturbing effects of the analogue, variant or homologue of nociceptin.

In one embodiment of the first aspect the compound is selected from Phe-Ser-Glu-Phe-Met-Arg-Gln-Tyr-Leu-Val-Leu-Ser-Met-Gln-Ser- Ser-Gln, Thr-Leu-His-Gln-Asn-Gly-Asn-Val, (both of which are produced as disclosed in WO 97/07208), and from Tyr-Gly-Gly-Phe-Leu-Arg-Arg-l le-Arg-Pro-Lys-Leu-Lys-Trp-Asp-Asn-Gln,<BR> Tyr-Gly-Gly-Phe-Met-Thr-Ser-Glu-Lys-Ser-Gln-Thr-Pro-Leu-Val- Thr,<BR> Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Gln-Phe-Lys-Val-Val-Thr and Tyr-Gly-Gly-Phe-Leu (all of which are produced as disclosed in WO 97/07212).

In a second embodiment of the first aspect the invention relates to the use of a compound of the general formula I (Xaa) Phe-Gly-Gly-Phe- (A')- (A2)- (A3)- (A4)- (A5)- (A6)- (A')- (AB)- (A9)- (A'°)- (A")- (A'2) _<BR> Gln-(Xaa) n (I) wherein A'is Thr, Leu or Met; A2 is Gly, Arg or Thr; A3 is Ala, Arg or Ser; A4 is Arg, lie Glu or Gln; A5 is Lys, Arg or Phe; A6 is Ser, Pro Lys; A'is Ala, Lys, Gtn or Val;

A8 is Arg, Leu, Thr or Val; A9 is lys, Pro or Thr; A'° is Tyr, Leu or Trp; A"is Ala, Asp or Val ; A12 is Asn, or Thr; and (Xaa) is any amino acid; n and m are integers wherein n + m is no more than 82; and wherein the amino ac- ids are each individually in either the D or L stereochemical configuration, or a pharmaceutically acceptable salt thereof, for the preparation of a pharmaceutical composition for the treatment of vasomotor disturbances, in particular the peripheral vasomotor effects known as hot flushes or hot flashes. The peptide of formula I is disclosed in WO 97/07212, wherein i. a. a procedure for the preparation thereof has been described.

In a third embodiment of the first aspect the compound is selected from the group consisting of Phe-Gly-Gly-Phe-Thr-Gly-Ala-Arg-Lys-Ser-Ala-Arg-Lys-Leu-Ala- Asn-Gln, Phe-Gly-Gly-Phe-Thr-Gly-Ala-Arg-Lys-Ser-Ala-Arg-Lys-Leu-Ala- Asn-Gln, Phe-Gly-Gly-Phe-Thr-Gly-Ala-Arg-Lys-Ser-Ala-Arg-Lys-Tyr-Ala- Asn-Gln, Phe-Gly-Gly-Phe-Thr-Gly-Ala-Arg-Lys-Ser-Ala-Arg-Lys-Leu-Ala- Asn-Gln and Phe-Gly-Gly-Phe-Thr-Gly-Ala-Arg-Lys-Ser-Ala-Arg-Lys-Tyr-Ala- Asn-Gln (all of which are produced as disclosed in WO 97/07212).

In a fourth embodiment of the first aspect the composition is in a form suitable for oral, nasal, transdermal, pulmonal, or parenteral administration.

In a fifth embodiment of the first aspect the compound is administered as a dose in the range from about 0.01 to about 100 g per patient per day, preferably from about 1 to about 1000 mg per patient per day, especially from about 10 to about 100 mg per patient per day, e. g. about 100 mg per patient per day.

In a sixth embodiment of the first aspect the amino acids are all in either the D or L stereochemical configuration, preferably the L stereochemical configuration.

However, the compounds of the invention may comprise both L and D amino acids.

In a second aspect the invention relates to a method for the treatment or prevention of vasomotor disturbances, in particular the peripheral vasomotor effects known as hot flushes or hot flashes or for alleviating symptoms of drug withdrawal in particular abstinence symptoms occuring during withdrawal from abusive drugs, the method comprising administering to a patient in need thereof an effective amount of nociceptin or an analogue, a variant or a homologue thereof, wherein 1 to 12 amino acid (s) have been deleted, 1-82 amino acid (s) have been added and/or 1-15 amino acid (s) have been substituted, or a pharmaceutically acceptable salt thereof, wherein the deletion (s), addition (s) and/or substitution (s) does not substantially reduce the vasomotor disturbing effects of the analogue, variant or homologue of nociceptin.

The effective, such as the therapeutically effective, amount of nociceptin or an ana- logue, a variant or a homologue thereof will depend upon the mode of administration, on the therapy desired, form in which administered, the subject to be treated and the body weight of the subject to be treated, and the preference and experience of the physician or veterinarian in charge.

In one embodiment of the second aspect the nociceptin or an analogue, a variant or a homologue thereof is administered as a dose with an effective amount in the range from about 0.01 to about 100 g per patient per day, preferably from about 1 to about 1000 mg per patient per day, especially from about 10 to about 100 mg per patient per day, e. g. about 100 mg per patient per day.

Within its scope the invention includes the D and/or L stereochemical configuration of all the amino acids which constitutes nociceptin and analogs, variants or homologs hereof.

As used herein the term"patient"comprises any mammal which may benefit from treatment or prevention of vasomotor disturbances, such as a human, especially if the mammal is a female, such as a woman. However,"patient"is not intended to be limited to a woman.

The compounds intended to be embraced by the present invention are such peptides which are disclosed in WO 97/07208 and/or in WO 97/07212, as well as close analogs thereof. For the purpose of facilitating the reading of the present description said compounds, e. g. nociceptin, analogs, variants and homologues of nociceptin as well as compounds of formula I are all together termed"nociceptins", however this term does not in any way limit the scope of the present invention. Methods of preparing these nociceptins are either conventional and known to the man skilled in the art, or described in WO 97/07208 or in WO 97/07212.

The term"nociceptin"is intended to comprise the peptide Phe-Gly-Gly-Phe-Thr-Gly- Ala-Arg-Lys-Ser-Ala-Arg-Lys-Leu-Ala-Asn-Gln, which peptide is disclosed in both WO 97/07208 and WO 97/07212.

The term"an analogue, a variant or a homologue thereof, wherein 1-12 amino acid (s) have been deleted, 1-82 amino acid (s) have been added and/or 1-15 amino acid (s) have been substituted"is intended to comprise nociceptin wherein 1-12 amino acid (s) have been deleted, 1-82 amino acid (s) have been added and/or 1-15 amino acid (s) have been substituted.

As used herein the term"treatment"is also meant to comprise profylactic treatment.

Within the present invention, the nociceptins may be prepared in the form of phar- maceutically acceptable salts, especially acid-addition salts, including salts of orga- nic acids and mineral acids. Examples of such salts include salts of organic acids such as formic acid, fumaric acid, acetic acid, propionic acid, glycolic acid, lactic acid, pyruvic acid, oxalic acid, succinic acid, malic acid, tartaric acid, citric acid, benzoic

acid, salicylic acid and the like. Suitable inorganic acid-addition salts include salts of hydrochloric, hydrobromic, sulphuric and phosphoric acids and the like. Further e- xamples of pharmaceutically acceptable inorganic or organic acid addition salts in- clude the pharmaceutically acceptable salts listed in Journal of Pharmaceutical Science, 66,2 (1977) which are known to the skilled artisan.

Also intended as pharmaceutically acceptable acid addition salts are the hydrates which the present nociceptins are able to form.

The acid addition salts may be obtained as the direct products of compound synthe- sis. In the alternative, the free base may be dissolved in a suitable solvent containing the appropriate acid, and the salt isolated by evaporating the solvent or otherwise separating the salt and solvent.

The nociceptins of this invention may form solvates with standard low molecular weight solvents using methods known to the man skilled in the art.

The nociceptins may be administered in pharmaceutically acceptable acid addition salt form or, where appropriate, as a alkali metal or alkaline earth metal or lower alkylammonium salt. Such salt forms are believed to exhibit approximately the same order of activity as the free base forms.

In a broad aspect the present invention relates to the use of a compound, e. g. selected from the nociceptins disclosed herein, for the preparation of a pharmaceutical composition for the treatment of vasomotor disturbances, in particular the peripheral vasomotor effects known as hot flushes or hot flashes, the compound being characterized by inhibiting cordal stimulated vasodilatation in"the pitched rat"and/or binding to nociceptin receptors (i. e. ORL-1 receptors as disclosed in WO 97/07212 and in WO 97/07208).

In a further aspect the invention relates to the use of a compound, e. g. selected from the nociceptins disclosed herein, for the preparation of a pharmaceutical composition

for alleviating symptoms of drug withdrawal in particular abstinence symptoms occuring during withdrawal from abusive drugs.

PHARMACEUTICAL COMPOSITIONS A pharmaceutical composition for use in accordance with the present invention comprises, one or more nociceptins as active ingredient (s), or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable carrier or diluent.

Pharmaceutical compositions containing nociceptins of the present invention may be prepared by conventional techniques, e. g. as described in Remington: The Science and Practise of Pharmacy. 19'"Ed. 1995. The compositions may appear in conventional forms, for example capsules, tablets, aerosols, solutions, suspensions or topical applications.

Typical compositions include nociceptins or a pharmaceutically acceptable acid addition salt thereof, associated with a pharmaceutically acceptable excipient which may be a carrier or a diluent or be diluted by a carrier, or enclose within a carrier which can be in the form of a capsule, sachet, paper or other container. In making the compositions, conventional techniques for the preparation of pharmaceutical compositions may be used. For example, the active compound will usually be mixed with a carrier, or diluted by a carrier, or enclose within a carrier which may be in the form of a ampoule, capsule, sachet, paper, or other container. When the carrier serves as a diluent, it may be solid, semi-solid, or liquid material which acts as a vehicle, excipient, or medium for the active compound. The active compound can be adsorbed on a granular solid container for example in a sachet. Some examples of suitable carriers are water, salt solutions, alcohol's, polyethylene glycol's, polyhydroxyethoxylated castor oil, peanut oil, olive oil, gelatine, lactose, terra alba, sucrose, cyclodextrin, amylose, magnesium stearate, talc, gelatine, agar, pectin, acacia, stearic acid or lower alkyl ethers of cellulose, silicic acid, fatty acids, fatty acid amines, fatty acid monoglycerides and diglycerides, pentaerythritol fatty acid esters,

polyoxyethylene, hydroxymethylcellulose and polyvinylpyrrolidone. Similarly, the carrier or diluent may include any sustained release material known in the art, such as glyceryl monostearate or glyceryl distearate, alone or mixed with a wax. The formulations may also include wetting agents, emulsifying and suspending agents, preserving agents, sweetening agents or flavouring agents. The formulations of the invention may be formulated so as to provide quick, sustained, or delayed release of the active ingredient after administration to the patient by employing procedures well known in the art.

The pharmaceutical compositions can be sterilised and mixed, if desired, with auxilia- ry agents, emulsifiers, salt for influencing osmotic pressure, buffers and/or colouring substances and the like, which do not deleteriously react with the active compounds.

The route of administration may be any route, which effectively transports the active compound to the appropriate or desired site of action, such as oral, nasal, pulmonary, transdermal or parenteral e. g. rectal, depot, subcutaneous, intravenous, intraurethral, intramuscular, intranasal, ophthalmic solution or an ointment.

If a solid carrier is used for oral administration, the preparation may be tablette, placed in a hard gelatine capsule in powder or pellet form or it can be in the form of a troche or lozenge. If a liquid carrier is used, the preparation may be in the form of a syrup, emulsion, soft gelatine capsule or sterile injectable liquid such as an aqueous or non-aqueous liquid suspension or solution.

For nasal administration, the preparation may contain a compound of formula I dissolved or suspended in a liquid carrier, in particular an aqueous carrier, for aerosol application. The carrier may contain additives such as solubilizing agents, e. g. propylene glycol, surfactants, absorption enhancers such as lecithin (phosphatidylcholine) or cyclodextrin, or preservatives such as parabenes.

For parenteral application, particularly suitable are injectable solutions or suspensi- ons, preferably aqueous solutions with the active compound dissolved in polyhydro- xylated castor oil.

Tablets, dragees, or capsules having talc and/or a carbohydrate carrier or binder or the like are particularly suitable for oral application. Preferable carriers for tablets, dragees, or capsules include lactose, corn starch, and/or potato starch. A syrup or elixir can be used in cases where a sweetened vehicle can be employed.

A typical tablet which may be prepared by conventional tabletting techniques may contain: Core: Active compound (as free compound or salt thereof) 100 mg Colloidal silicon dioxide (Aerosil) 1.5 mg Cellulose, microcryst. (Avicel) 70 mg Modified cellulose gum (Ac-Di-Sol) 7.5 mg Magnesium stearate Ad.

Coating: HPMC approx. 9 mg *Mywacett 9-40 T approx. 0.9 mg *Acylated monoglyceride used as plasticizer for film coating.

Any novel feature or combination of features described herein is considered essential to this invention.

Pharmacological effects: Male Sprague Dawley rats (30025 g) were anaesthetised with pentobarbital sodium (50 mg/kg i. p.) and polyethylene catheters were positioned in both femoral veins for the intravenous administration of drugs, such as nociceptin and analogues, and into the left femoral artery in order to measure arterial blood pressure and heart rate. The trachea was cannulated with polyethylene tubing and the rat was pithed, ventilated and drug treated as described by Nuki Y. et al. (Effects of Dorsal Rhizotomy on Depressor Response to Spinal Cord Stimulation Mediated by Endogenous Calcitonin Gene-related Peptide in the Pithed Rat. J. Neurosurg. 1993; 79: 899-904).

Results: Electrical stimulation of the rod at 4 Hz induced a profound decrease in arterial blood pressure which could be completely blocked by nociceptin and the nociceptin analogues.