"Composition comprising nexrutine for use in patients with early prostate cancer"

TECHNICAL FIELD

The present invention relates to nexrutine (Nx) or its compositions for use in a method for the preventive or curative treatment of stage I prostate cancer in a specific subset of patients.

STATE OF THE ART

Prostate cancer is a tissue formation consisting of cells that grow in an uncontrolled and abnormal manner within the prostate gland and has become the most frequent cancer in the male population of Western countries.

In its early stages of development, prostate cancer is entirely asymptomatic, which is why it is difficult to detect it by early diagnosis. As the tumour mass grows, the typical symptoms of the disease begin: difficulty in urination, especially the start, need to urinate frequently, feeling of feeling of unemptied bladder and the presence of blood in the urine or semen.

There are screening tests that can be used to diagnose the presence of prostate cancer. First of all is the assay of prostate-specific antigen (PSA). Prostate biopsies, transrectal ultrasound and magnetic resonance imaging (MRI) may be performed if a urology visit reveals a suspicion of presence of prostate cancer.

Once prostate cancer is diagnosed, it is classified. Depending on stage (I, II, III, IV), different therapeutic treatments, all of which have significant unwanted effects, are used. Usually when stage IV is diagnosed, treatment with hormone therapy is the most commonly used treatment. Local therapy with surgery or radiotherapy may also be recommended to help control symptoms. In the case of stage III or stage II cancer, surgery, radiotherapy, brachytherapy or proton therapy and hormone therapy are usually performed.

In case of stage I cancer instead, therapeutic and treatment approaches are reduced to active surveillance or watchful waiting. Above all, in the case of older men, or with serious health problems, a watchful waiting regime is usually undertaken. Although radical prostatectomy or radiotherapy are sometimes used, they are generally considered to be disproportionate approaches.

Therefore, in the case of stage I cancer, there is a limited therapeutic choice which envisages undergoing surgery or to live with the cancer. Although this is often a source of discomfort both for subjects with cancer and their partners, the alternative - surgery or radiotherapy - entails risks and potential significant side effects.

As regards active surveillance (AS), although there is increasing recognition of it as a reasonable prostate cancer management option, it is chosen by only 10% of men (United States statistics) (Andriole et aL, 2009). Furthermore, these subjects often live with a state of anxiety due to "non-action", and the idea of being in a "wait and see" condition.

These observations apply to all those subjects who are in a post-operative monitoring phase of tumours considered to be low risk. Even in these cases, the subjects are subjected to an active surveillance regime during which PSA, TNM stage, and Gleason score are measured to monitor the course and risk of recurrence. It is therefore clear that there is a therapeutic shortage of therapies that allow to slow or prevent the development of an initial stage of cancer, and that there is a need to support patients with early stage prostate cancer (stage I).

In particular, there is a therapeutic vacuum in the case of the subset of patients with stage I prostate cancer, characterised by the following clinical parameters:

- cTl-T2a;

- Gleason score <6;

- PSA <10 ng/ml.

These patients are usually subjected to an active surveillance or watchful waiting regimen where no therapeutic action - other than - monitoring is taken, or they are subjected to interventional therapies that are deemed disproportionate in most cases.

Therefore, there is the strong need for the identification of new treatments that can reduce/slow down the development of early prostate cancer (stage I) and the development of cancer in more advanced stages (stage II, III, or IV), which are highly effective in a broad spectrum of subjects, well tolerated and without side effects.

Novel treatments should be directed toward the problem of relapses and/or that prevent the development of the cancer in more advanced stages (stage II, III, or IV).

Following an intense and extended research and development activity, the Applicant surprisingly found that the use of nexrutine, or its compositions for use, is effective in the treatment of stage I prostate cancer, particularly in subjects with certain clinical parameters.

The use of nexrutine, or its compositions for use, subject of the present invention has been found to reduce, delay or reverse the progression of cancer located in the prostate in subjects with stage I prostate cancer characterised by the following clinical parameters (Low risk/very low risk class);

- cTla, cTlb, cTlc, o cT2a; and

- Gleason score <6; and

- PSA <10 ng/ml.

The use of nexrutine according to the present invention, or its compositions for use, potentially enables to prevent/slow down the development of stage I prostate cancer into stage II, III and IV prostate cancer, and to reduce or slow down the onset of relapses in subjects subjected to surgery or radiotherapy treatment to remove a stage I cancer.

The compositions of the present invention do not have significant side effects and they can be administered to all categories of subjects in need, including elderly men or those with other comorbidities, who normally cannot be subjected to any other type of therapy.

Furthermore, the compositions of the invention comprising nexrutine (in short, compositions of the invention) can be advantageously formulated for oral administration.

Lastly, the compositions of the present invention are easy to administer and not particularly complicated or demanding to prepare. Even in terms of cost-effectiveness, it is advantageous with respect to medical or surgical therapies.

These and other objects which will be apparent from the detailed description that follows, are achieved by the compositions of the present invention due to the technical characteristics claimed in the attached claims. BRIEF DESCRIPTION OF THE INVENTION

The present invention relates to nexrutine for use in the treatment of stage I prostate cancer, wherein said nexrutine is administered to a subset of patients characterised by the following clinical parameters:

- a TNM stage: cTla, cTlb, cTlc, or cT2a; and

- PSA values <10 ng/ml; and

- a Gleason score <6 (grade 1).

Furthermore, the present invention relates to a nexrutine composition for use according to any one of the embodiments described in the present context and at least one pharmaceutical or food grade additive.

BRIEF DESCRIPTION OF THE FIGURES

FIGURES 1 and 2: Details of classification of prostate cancer stages.

FIGURE 3: AIOM (Italian Association of Medical Oncologists) guidelines summary scheme Edition 2020.

FIGURE 4: Life expectancy rates reported in OECD data (2021), "Life expectation at birth (indicator), doi: 10.1787/27e0fc9d-en (Accessed on 27 August 2021)".

FIGURE 5 A and B: Representation of a Tla clinical (on the left) and Tib clinical (right) prostate cancer, as reported in AJCC Manual 8 ^th edition.

DETAILED DESCRIPTION OF THE INVENTION

Definitions "Prostate": prostate is a gland the size of a chestnut present in the male organism, located anterior to the rectum. It plays an important role in reproductive functions, and it is affected by the action of hormones.

"Active surveillance": (AS) active surveillance consists of closely monitoring cancer without administering immediate treatment. Active surveillance is intended to avoid unnecessary treatment that could cause unpleasant unwanted effects. Physicians generally check blood PSA levels and perform prostate biopsies or magnetic resonance imaging (MRI) during active surveillance. If the cancer progresses, the physician will recommend appropriate curative treatment.

"Watchful waiting": (WW) consists of closely monitoring cancer without administering immediate treatment. This approach envisages fewer follow-up examinations with respect to active surveillance. It is generally an option for men with low risk localised prostate cancer.

"PSA": prostate-specific antigen. PSA is a protein produced by the prostate and it is usually found in the semen and in traces released into the bloodstream. Although not a guarantee of prostate cancer, PSA levels tend to increase when there is a problem with the prostate. PSA is measured through blood sampling, results are reported in nanograms of PSA per millilitre of blood (ng/ml).

"Treatment of a stage I cancer": It refers to the to the reduction or slowing of a stage I cancer.

"Preventive treatment of a stage II, III, IV cancer" is used to indicate a use that enables to prevent or delay the progression of a stage I cancer into later stages, or to reduce the risk of relapse, for example, in patients successfully subjected to treatment of stage I cancer. Below is a detailed description of clinical parameters used to define the subset of patients of interest according to the present invention. These parameters are as defined and updated during the eighth edition of the (AJCC) American Joint Committee on Cancer “Cancer staging edition", whose content - relevant to the present invention

- is incorporated here for reference (page 723-734 of the manual) and reproduced hereinafter.

Classification in prostate cancer stages is carried out using multiple tests in order to evaluate the aggressiveness of the cancer in cells and its spread.

Generally, the stage is evaluated based on three parameters (described and used in the context of the present invention, following AJCC guidelines):

- Staging (Stage T) (TNM category) (cancer stage);

- Gleason score/grade (Grade Group);

- PSA levels.

TNM CLINICAL STAGING (CTNM)

In the present context, one of the parameters evaluated is clinical staging (cTNM). Staging is a conventional way of indicating the location and size of the cancer. This method enables to determine whether the disease has spread to other anatomical structures, that is whether there are metastases.

As understood in the present context, a transrectal fine needle aspiration biopsy of the prostate gland or a TRUS (transrectal ultrasonography) is usually performed in order to obtain the cinema classification. TNM staging is considered the clinical "gold standard" for prostate cancer and it is used as a basis for guiding the treatment decision making process. The TNM clinical classification/staging as described and used in the present context is in accordance with the AJCC guidelines (8 ^th edition) and it is reported in table 1 below.

In detail, in the TNM clinical staging system (cTNM) T indicates the extent of the cancer, N indicates the involvement of the lymph nodes and M indicates the presence of metastases.

The prostate cancer stages according to the TNM system are usually divided into:

Table 1 - AJCC Definitions (8 ^th Edition). Definition of primary cancer (T), clinical T (cT).

In the light of the above, it is therefore clear that in the present context cTla is used to indicate prostate cancer when it is found incidentally in less than 5% of resected tissue (See Figure 5a).

In the present context, cTlb is used to indicate cancer when found in more than 5% of resected tissue.

(See Figure 5b). In the present context, cTlc is used to indicate prostate cancer when found in both lobes of the prostate.

In the present context, cT2a is used to indicate prostate cancer when it affects half of a single lobe or less.

Advantageously, the subjects treated in the present context have N=0 and M=0 in the TNM staging system.

GLEASON SCORE/GRADE GROUP (1-5) Gleason score is a highly prognostic factor for prostate cancer that describes the microscopic architecture of cancer tissue. The standard procedure for evaluating Gleason scores, that is biopsy, consists in removing the prostate tissue so as to observe it under the microscope. Currently, biopsies are guided by the transrectal ultrasonography (TRUS).

The test yields scores ranging from 2 to 10 as reported in Table 2 below.

Table 2

Recently, the Gleason system was grouped into the so-called grade system. However, the AJCC guidelines (8 ^th edition of the "Cancer Staging Manual") recommend to report both the grade and Gleason score.

Grade grouping is based on the histologic pattern of arrangement of carcinoma cells in hematoxylin and eosin-stained sections. Five basic grade patterns are used to generate

Grade groups ranging from 1 to 5.

The grade group is the stratification of Gleason histological grade scores into prognostically relevant groups. They are as reported in Table 3 below.

Table 3 - AJCC Guidelines according to the 8 ^th edition of the cancer staging manual.

CLASSIFICATION OF PSA LEVELS

PSA is a protein produced by prostate gland cells. PSA level is measured in the blood. The results are reported as nanograms of PSA per millilitre (ng/mL) of blood. The higher the PSA level in men, the higher the risk of diagnosis and mortality from prostate cancer.

Therefore, in the present context, PSA <10 ng/ml is used to indicate blood prostatespecific antigen values below 10 ng/ml, measured through blood analysis using standard clinical methods known in the industry. In general, the classification of PSA levels according to the AJCC guidelines is as reported in table 4 below.

Table 4 PSA level below 10 ng/mL is considered low, from 10 to 20 ng/mL is considered intermediate, and when above 20 ng/mL it is considered high.

NEXRUTINE AND ITS COMPOSITIONS

The present invention relates to nexrutine and its compositions comprising nexrutine as an effective ingredient to slow or stop stage I prostate cancer, in a subset of patients characterised by specific clinical parameters.

The nexrutine in the present invention is mixture of an extract of a bark of Phellodendron amurense (philodendron) and Berberine. The composition of the present invention is used in the reduction and/or slowing of stage I prostate cancer in a subset of patients characterised by specific clinical parameters, as described in the present context.

Subjects with stage I prostate cancer treated in the present context are that subset of patients characterised by the following clinical parameters:

- a TNM stage: cTla, cTlb, cTlc, or cT2a;

- PSA values <10 ng/ml;

- a Gleason score <6 (grade 1).

Preferably, the treated subjects are further characterised by the following parameters:

- less than three positive core needle biopsies with <50% neoplasm in each core needle, evaluated by analysing under the microscope;

- PSA density <0.15 ng/ml/g, measured through blood tests using a standard clinical method.

Therefore, when the subjects are characterised in that they have:

- PSA values <10 ng/ml; and - a Gleason score <6;

- a TNM stage; Tic; and

- less than three positive core needle biopsies with <50% neoplasm in each core needle; and/or

- PSA density <0.15 ng/ml/g, measured using a standard clinical methods.

Patients diagnosed with prostate cancer using these clinical parameters are classified as "low or very low" risk patients.

To date, this type of cancers is not treated if not surgically or with radiotherapy, both invasive treatments, with a significant post-operative course or with considerable side effects. Alternatively, the patient is subjected to the so-called "Active surveillance", or "watchful waiting" and the progress of the disease is monitored.

The present invention falls within this context and proposes nexrutine for use in a method for the treatment of stage I prostate cancer, in patients with low-risk or very low-risk prostate cancer.

These subjects may have a life expectancy of > 10 years or comprised within 10 years. This generally has a significant impact on the therapeutic choice or on the use of active surveillance or watchful waiting.

Life expectancy as understood in the present context is defined as the average time a male person can expect to live, depending on the mortality rates valid at the time of filing of the application. These rates vary depending on the nationality. Therefore, they will have to be evaluated according to life expectancy in the country where the patent is in force. An overview with the recommendations valid as of 2021 reported by the OECD is shown in Figure 4. For example, the life expectancy of a male subject in Italy in 2020-2021 is 80 years. Therefore, as a result the compositions according to the present invention are preferably for use in subjects about <80 years of age, preferably <70 years of age.

Advantageously, the compositions according to the present invention can be administered during the period of active surveillance or watchful waiting.

Advantageously, nexrutine, the present invention, can be administered during the period of active surveillance or watchful waiting and following surgery so as to avoid or reduce the risk of relapse.

The compositions according to the present invention are for concomitant use with radiotherapy treatments.

Therefore, nexrutine can also be used as an adjuvant or co-adjuvant in surgical or radiant therapy.

In all cases, the use of nexrutine is independent of the life expectancy of the subject.

Nexrutine used in the present context is a mixture of an extract of a bark of Phellodendron amurense and Berberine. Phellodendron amurense is a tree belonging to the family of rutacee (Rutacea). Berberine is a plant alkaloid present in the bark, roots and stems of plants belonging to the genus Berberis, such as common barberry (Herbers vulgaris L.).

Common barberry is a plant of the family of Berberidaceae and is commonly found both in Asia and Europe. There are several species of this plant, including Berberis aristata L. It is one of the most used in traditional oriental medicine.

Extracts of philodendron have also been traditionally used in Chinese medicine for hundreds of years as anti-diarrhoeal, astringent and anti-inflammatory agents. Nexrutine is considered a natural treatment for pain and inflammation in the United States.

Surprisingly, the authors of the present invention discovered that nexrutine can be advantageously used in the treatment of stage I prostate cancer in subjects characterised by certain clinical parameters.

Therefore, the present invention provides a pharmaceutical composition comprising nexrutine, for treating stage I prostate cancer, in a specific subset of subjects. Furthermore, the composition according to the present invention allows to reduce the risk of relapse into stage I prostate cancer, after surgery or radiotherapy.

Therefore, forming an object of the present invention is nexrutine, a composition comprising berberine and extract of the philodendron bark for use in a method for the treatment of Stage I prostate cancer characterised by:

- a TNM stage: cTla, cTlb, cTlc, or cT2a;

- PSA values <10 ng/ml;

- a Gleason score <6; said composition comprises:

- nexrutine, preferably in a concentration comprised from 59 % to 66 %, of berberine by weight with respect to the total weight of the composition and extract of the bark of phellodendron amurense between 12 % and 15 %;

- completed by corn starch 14-18% and calcium phosphate 5-7%.

In the present context, nexrutine is used to indicate a mixture of an extract of a bark of Phellodendron amurense and Berberine.

Nexrutine used in the present context is obtained by mixing the aforementioned extracts that can be obtained through commonly known extraction processes, but also available on the market for purchase. The purity of the extracts used herein is always pharmaceutical and/or food grade.

Nexrutine used in the present context contains isoquinoline alkaloids such as berberine, palmatine (1.2%), philodendron (0.5%), jatrorrhizine (0.5%) and magnoflorine (up to 1.1%, candicine (0.5%) and liminoid, limonin.

One type of nexrutine that can be used in the present context may be in powdered form and have the following chemical composition (table 5).

Table 5

For example, it may be the nexrutine produced and sold by InterHealth Nutraceuticals under the trade name Nexrutine*. The composition according to the present invention may further comprise at least one pharmaceutical or food grade additive. Said at least one acceptable pharmaceutical or food grade additive and/or excipient can be selected from all substances known to the man skilled in the pharmaceutical art or skilled in preparing food products, such as preservatives, emulsifiers and/or thickeners such as for example hydroxymethyl cellulose, sweeteners, dyes such as for example E171 dye, natural and artificial flavours, antioxidants, stabilisers, fillers, anticaking agents such as for example vegetable magnesium stearate, fatty acid magnesium salts and silicon dioxide, bulking agents such as for example microcrystalline cellulose and mixtures thereof.

For example, pharmacologically acceptable additives which can be used in the composition according to the present invention may be selected from the group consisting of corn starch, dibasic calcium phosphate, silicon dioxide and mixtures thereof.

The composition according to the present invention may contain nexrutine in an amount by weight comprised from 71% and 81%, with respect to the total weight of the composition.

Preparation of the bark of the extract of Phellodendron amurense.

The extract obtained from the bark of Phellodendron is dried and pulverised. The loss on drying preferably does not exceed 12% by weight. For example, it can be in a range from 10% to 3% by weight, preferably comprised from 9% to 5%.

The content of berberine, preferably berberine chloride is not less than (<) 59% by weight with respect to the total content, in a range preferably comprised from 59% to 66%. As understood in the present context, "it is not less than" means that the Berberine titre is in an amount of 50% by weight or in a lower amount. This amount of berberine is measured using standard analytical HPLC techniques. Preferably the expression Nexrutine in the present context is used to indicate a mixture of an extract of bark of Phellodendron amurense and Berberine comprising an amount by weight (titre) in berberine of at least 50%, at least of 60%, at least of 70%.

Preferably, nexrutine according to the present invention comprises an amount by weight (titre) in berberine of at least 50%, of at least 60%, of at least 70%.

Berberberine is a quaternary ammonium salt (5,6-dihydro-9,10- dimethoxybenzo[g]benzodioxolo[5,6-a]quinolizinium, identified for example with CAS No. 2086-83-1, chemical formula C2OHISN04 ⁺ ) of the protoberberine group of benzyl isoquinoline alkaloids. Berberine comprised in the extract used in the present context preferably berberine chloride, that is the hydrochloric salt form of berberine.

Advantageously, said nexrutine is administered as a composition of the invention to a subject in need an oral daily dose which comprises nexrutine in an amount comprised in the range from 500 mg per day to 1500 mg per day.

The aforementioned daily doses can be administered to the subject in need in a single dose (one dose) or in repeated doses, for example two, three daily doses.

Said compositions of the invention, according to any one of the described embodiments, may be a pharmaceutical composition (or Live Biotherapeutic Products), a medical device composition, a dietary supplement, a food (or novel food or food for special medical purposes), a composition for a dietary supplement or food, or, alternatively, a composition for cosmetic use.

Unless specified otherwise, the expression composition or other comprising a component at an amount "comprised in a range from x to y" is used to indicate that said component may be present in the composition or other at all the amounts present in said range, even though not specified, extremes of the range comprised. Unless specified otherwise, the indication that a composition "comprises" one or more components or substances means that other components or substances can be present besides the one, or the ones, indicated specifically.

The expression "subject/s" in the context of the present invention is used to indicate mammals, preferably male human subjects.

The expression "medical device" in the context of the present invention is used in the meaning according to Legislative Decree n° 46 dated 24 February 1997, or according to the new Medical Device Regulation (EU) 2017/745 (MDR).

In the context of the present invention, the term "novel food" is used in the meaning according to Regulation EC 258 dated 1997.

EXPERIMENTAL PART

- Active surveillance: can treatment with Nexrutine (Nx) delay the progression of cancer in patients under AS? To answer the question, there is carried out a prospective study to see if patients chronically treated with Nx show better results in the long term with respect to control patients.

- Before prostatectomy: Do patients treated with Nx prior to RP have a benefit in terms of histopathological disease and long-term results?

- After prostatectomy: does Nx have any impact on avoiding BCR? After prostatectomy, does the treatment decrease the incidence of BCR?

- Before RT: Can treatment with Nx effectively increase the efficacy of RT? Is it possible to minimise radiation dose in Nx-treated patients with overlapping results? - Potential association and potential benefit in patients under ADT.

Clinical studies are carried out to evaluate the aforementioned aspects appropriately.

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