WO2007137380A1

WO2007137380A1 - Pharmaceutical product based on passiflora incarnata l., uses therefor and method to treat anxiety and insomnia

Info

Publication number: WO2007137380A1
Application number: PCT/BR2007/000127
Authority: WO
Inventors: Luiz Francisco Pianowski
Original assignee: Aché Laboratórios Farmacêuticos S/A
Priority date: 2006-05-25
Filing date: 2007-05-24
Publication date: 2007-12-06
Also published as: BRPI0602106B8; BRPI0602106B1; BRPI0602106A

Abstract

The present invention generally refers to a pharmaceutical product in powder based on Passiflora incarnata L., substantially lacking alkaloids, providing better safety to patients, keeping pharmacological action over anxiety and insomnia.

Description

"PHARMACEUTICAL PRODUCT BASED ON PASSIFLORA INCARNATA L, USES THEREFOR AND METHOD TO TREAT ANXIETY AND INSOMNIA"

FIELD OF INVENTION

The present invention generally refers to a powdered pharmaceutical product based on Passiflora incarnate L, substantially lacking alkaloids, which does not cause side effects to patients, keeping the pharmacological action over anxiety, insomnia, pharmaceutical compositions containing said product and its preparation processes.

BACKGROUND OF THE INVENTION Passiflora incarnata Linne is a plant from the family

Passifloraceae, traditionally used to combat anxiety and insomnia states. Various products obtained from leaves, flowers and fruit of Passiflora incarnata L. are known and commercialized worldwide as anxiolytic, antiseptic, anticonvulsive and analgesic. Passiflora incarnata L. is chemically constituted by flavonoids, sterols, cyanoglucosides, lignanes, fatty acids, alkaloids, tanines and others. The anxiolytic and sedative properties are attributed to two of its chemical constituents: alkaloids and flavonoids (Behavioural effects of Passiflora incarnata L. and its lndol Alkaloid and Flavonoid Derivatives and Maltol in the Mouse, J. Ethnopharmacol., 1997 Jun; 57 (1): 11-20).

However, toxicity cases connected to the ingestion of Passiflora incarnata L have been reported in the last few years. Hypersensitivity with cutaneous vasculitis and urticaria in humans, after ingestion of pellets containing Passiflora incarnata L, was reported by Vasculitis Associated with Herbal Preparation Containing Passiflora Extract, Brit. J. Rheumat, 1993; 32: 87-88). The plant is also associated to IgE mediator, asthma and rhinitis (Occupational Respiratory Allergic Disease Induced by Passiflora allata and Rhamnus purshiana, Ann. Allergy Asthma Immun., 1997; 79: 449-454). More severe cases have also been reported, with the hospitalization of patients due to the reduction of the consciousness level after ingestion of Passiflora (A Herbal Product Used for Intoxication, Tidsskr Nor Loegeforen, 1997; 117: 1140-1141) and cases of severe gastrointestinal and cardiovascular toxicity after the ingestion of therapeutic doses of anxiolytic medicine based on Passiflora incarnata L (Toxicity of Passiflora incarnata L₁ Clinical Toxicology, 2000, 38 (1), 63-66).

Causes of toxicity events associated to products based on Passiflora incarnata L. are little known in the pharmaceutical field. Therefore, the development of new products avoiding such undesired side effects to patients is desired.

DESCRIPTION OF THE INVENTION

Research made by the applicant has shown that side effects associated to the products based on Passiflora incarnata L. are attributed to the presence of alkaloids, particularly alkaloids with harmanic nucleus.

Alkaloids with harmanic nucleus are part of the β-carbolinesgroup , which are organic amines present in plants and animals.

Alkaloids are present in products based on Passiflora incarnata L, generically considered the active principle responsible for their therapeutically effects. On the contrary, it was verified that they promote a series of pharmacological actions in the cardiovascular and central nervous system , they induce bradichardia and ventricular arrhythmia, interaction with neurotransmitter metabolism and inhibition of the bowel smooth muscle.

Furthermore, people with polymorphic variation in the xenobiotic gene metabolism, like cytochrome P450 2D6, are prone to severe toxicity after alkaloid ingestion.

The present invention provides a powdered pharmaceutical product based on Passiflora incarnata L₁ substantially lacking alkaloids, which does not cause side effects to patients, maintaining the pharmacological action over anxiety and insomnia and convenience of use.

The standardized product of the present invention is obtained by means of a process that starts by extracting leaves of Passiflora incarnata L, particularly dry and milled, in hydroalcoholic solution with about 30% lower alcohols, particularly methanol, ethanol, propanol, butanol or their mixtures.

The extraction is conducted at a substantially constant temperature, between about 70 ⁰C and about 90 ⁰C, particularly about 80 ⁰C, under agitation for a period of about three hours. The temperature and time of residence provide thermal degradation of a substantial part of the alkaloids with harmanic nucleus and are important to obtain a product substantially lacking harmful substances, but keeping at the same time the appropriate pharmacological action over anxiety and insomnia. After cooling, the remaining alkaloids are removed by means of physical-chemical processes known to the person skilled in the art, but which should also be conducted according to a specific manner to obtain the product of the present invention.

Said means of alkaloid removal include one or more of (b1) ultrafiltration, (b2) removal with organic solvents, (b3) precipitation, (b4) distillation and (b5) ionic exchange resins.

In an appropriate alternative, ultrafiltration (b1) is effected in an equipment with membranes of about 10,000 Dalton.

In a first alternative, the removal of alkaloids (b2) by organic solvents particularly comprises the sequential steps of acidulation, to form alkaloid salts and their recovery. In a second embodiment, the removal of alkaloids (b2) particularly comprises the sequential steps of alkalinization with an organic solvent, acid concentration, alkalinizing and recovery. Hydrochloric acid is an appropriate acid and chloroform is an appropriate organic solvent to recover alkaloids .

Precipitation of alkaloids (b3) particularly comprises the sequential steps of adding hydroxide, particularly calcium and/or sodium hydroxide, and simple filtering.

Distillation (b4) is appropriately achieved in an alkalinized medium to avoid resinification of the alkaloids, and the use of ionic, particularly cationic exchange resins (b5), appropriately comprises sequential steps of extraction in acid solution, passage through the resin and elution with basic solution. After the removal of the remaining alkaloids, concentration in a vacuum chamber is performed at a maximum temperature of about 80 ⁰C, preferably about 70 ⁰C, up to about 20 to about 25% solids.

Hygroscopic carriers, particularly dextrin or corn starch, are advantageously added in the sequence, and spray dryer dehydration is undertaken.

Hygroscopic carriers have inert loads and, besides being drying aids, also have the function of product standardization, so as to keep constant the contents of isovitexin and the product to remain in the form of a fluid fine powder. The inlet temperature in the spray dryer equipment varies between about 190 ⁰C and 230 ⁰C, particularly about 210 ⁰C, the outlet temperature in the equipment varies between about 75 ⁰C and 95 ⁰C, particularly about 85 ⁰C.

The powdered pharmaceutical product of the present invention contains about 1 to about 10%, particularly about 7% by weight, of isovitexins and pharmaceutically acceptable carriers, particularly dextrin, corn starch or their mixtures, and may be either directly administered to the patient or be included in pharmaceutical compositions, in quantities between 1 and 3000 mg, to treat anxiety and/or insomnia, once or more times per day. By essentially lacking alkaloids, it is meant that products based on

Passiflora incarnata L. contain 1 ppm or less of alkaloids with harmanic nucleus.

In another aspect, the present invention refers to pharmaceutical compositions containing about 1 to about 3000 mg of the product based on Passiflora incarnata L of the invention and pharmaceutically acceptable excipients.

Pharmaceutically acceptable excipients are e. g. , but not limited to, the ones mentioned in the book Remington's Pharmaceutical Sciences, from the U. S. publisher Mack Publishing. In another aspect, the present invention refers to a method for treatment of anxiety and insomnia, characterized by the fact of administering to a patient in need of such treatment a daily amount of 1 to 3000 mg of the product, or pharmaceutical composition, of the present invention.

Merely illustrative examples of a specific embodiment of the present invention are presented below, not creating any limitation to its scope beyond those contained in the attached claims.

EXAMPLES

Preparation process by ultrafiltration

100 kg of Passiflora incarnata L leaves were milled and added to a reactor containing 1 ,000 I of a hydroalcoholic solution (30% ethanol). The mixture was kept for three hours under agitation at constant temperature of 80 ⁰C for part of the alkaloids to be thermally degraded.

After cooling, the mixture passed through an ultrafiltration system comprising 10,000 Dalton membranes to remove the remaining alkaloids. The mixture was concentrated within a vacuum chamber at maximum temperature of 70 ⁰C up to 20-25% solids.

5 kg dextrin were added and the mixture was dried in a spray dryer with inlet temperature of 210 ⁰C and outlet temperature of 85 ⁰C. 100 kg of a hygroscopic dry fine powder containing dextrin and 7% isovitexins, substantially free from alkaloids (as measured by a spectrophotometric method) were obtained.

EXAMPLE 2 PHARMACOLOGICAL ASSAYS

Comparative pharmacological assays were run for anxiolytic actions of standardized products based on Passiflora incarnata L₁ both with and without alkaloids. Assays were performed with mice and the control (C) was a common saline solution. The results as presented in Figure 1 show that 200 mg/kg oral dosage of the extract of Passiflora incarnata L. with and without alkaloids, did not produce significant reduction of the motor activity when evaluated by the open field assay, after 1 hour. A similar result was noticed in animals treated with diazepam (1 mg/kg, intraperitonial., 15 min). Each column represents the average of six to eight experiments and vertical bars show standard deviations from the average.

The removal of alkaloids did not significantly affect the anxiolytic activity. On the contrary, the comparative assay showed that products with and without the presence of alkaloids provided the same therapeutical effect with slight unexpected increase in the anxiolytic action of the product without alkaloids.

EXAMPLE 3 EFFECT OF ALKALOIDS OVER VENTRICULAR REPOLARIZATION

Graphs of Figures 2 and 3 represent the action of an alkaloid with harmanic nucleus, harmalol, over ventricular repolarization.

In the graph of Figure 2, line 1 represents T20, line 2 represents T50 and line 3 represents T90.

When the percentual increase of each interval in the heart submitted to alkaloid of harmanic nucleus is considered (graph of figure 3), a clear increase in T20 is verified, representing the plateau phase of the potential of action.

The plateau phase is crucial to determine the duration of myocardial concentration, providing appropriate relationship between the times of systole and diastole and a cardioprotectant window wherein re-excitation cannot occur, inhibiting the appearance of arrhythmia.

Alkaloids with harmanic nucleus cause modification of the plateau, inducing the increase in repolarization, which improves vulnerability against ventricular arrhythmias.

Claims

1. PROCESS TO PREPARE A PRODUCT BASED ON PASSIFLORA INCARNATA L₁ characterized by comprising the steps of: a. extraction of leaves in hydroalcoholic solution, keeping substantially constant shaking and temperature, for a period of about three hours; b. removal of remaining alkaloids by means of physical-chemical processes; c. concentration under maximum temperature of 80 ⁰C to about 20 to about 25% solids; and d. dehydration in the presence of hygroscopic carrier.

2. PROCESS of claim 1 , wherein the temperature of step (a) varies between about 70 ⁰C and about 90 ⁰C.

3. PROCESS of any of claims 1 or 2, wherein the temperature of step (a) is about 80⁰C.

4. PROCESS of claim 1 , wherein the leaves of Passiflora incarnata L. are dried and milled before step (a).

5. PROCESS of claim 1 , wherein the hydroalcoholic solution contains about 30% lower alcohols.

6. PROCESS of any of claims 1 or 5, wherein lower alcohols are selected from methanol, ethanol, propanol, butanol or their mixtures.

7. PROCESS of claim 1 , wherein a substantial part of alkaloids is removed by thermal degradation in step (a).

8. PROCESS of claim 1 , wherein the physical-chemical processes of step (b) may be one or more from (b1) ultrafiltration, (b2) removal with organic solvents, (b3) precipitation, (b4) distillation or (b5) ionic exchange resins.

9. PROCESS of claim 8, wherein (b1) is made in an equipment with membranes of about 10,000 Dalton.

10. PROCESS of claim 8, wherein (b2) comprises the sequential steps of acidulation and recovery in organic solvent.

11. PROCESS of claim 8, wherein (b2) comprises the sequential steps of extraction in alkaline medium and organic solvent, acid concentration, basification and recovery in organic solvent.

12. PROCESS of any of claims 10 or 11 , wherein the acid is hydrochloric acid and the organic solvent is chloroform.

13. PROCESS of claim 8, wherein (b3) comprises the sequential steps of hydroxide addition and filtration.

14. PROCESS of claim 13, wherein the hydroxide is calcium and/or magnesium hydroxide.

15. PROCESS of claim 8, wherein (b4) is made in alkalinized medium.

16. PROCESS of claim 8, wherein (b5) comprises sequential steps of extraction in acid solution, passage through a cationic resin and elution with basic solution.

17. PROCESS of claim 1, wherein the temperature of step (c) is not higher than 70 ⁰C.

18. PROCESS of claim 1 , wherein dehydration is made by spray dryer.

19. PROCESS of claim 18, wherein the inlet temperature in the equipment varies between about 190 ⁰C and 230 ⁰C and the outlet temperature in the equipment varies between about 75 ⁰C and 95 ⁰C.

20. PROCESS of any of claims 18 or 19, wherein the inlet temperature in the equipment is about 210 ⁰C and the outlet temperature in the equipment is about 85 ⁰C.

21. PROCESS of claim 1, wherein the hygroscopic carrier is dextrin, corn starch or their mixtures.

22. PROCESS of any of claims 1 to 21 , wherein removed alkaloids have harmanic nucleus.

23. PHARMACEUTICAL PRODUCT in powder based on Passiflora incarnata L., obtained as per any of claims 1 to 24, which contains about 1 to about 10% of isovitexins, about 1 ppm or less of alkaloids and pharmaceutically acceptable carriers.

24. PRODUCT of claim 23, which contains about 7% isovitexins.

25. PRODUCT of claim 24, wherein the carrier is dextrin, corn starch or their mixtures.

26. USE OF THE PRODUCT of any of claims 23 to 25, characterized by being intended to prepare a medicine to treat anxiety and/or insomnia.

27. PHARMACEUTICAL COMPOSITION characterized by comprising about 1 to about 3000 mg of the product as claimed by claims 23 to 25 and pharmaceutically acceptable excipients.

28. USE OF THE PHARMACEUTICAL COMPOSITION of claim

27, characterized by being intended to prepare a medicine to treat anxiety and/or insomnia.

29. METHOD TO TREAT ANXIETY AND INSOMNIA, characterized by giving a patient in need daily quantity of 1 to 3000 mg of the product as claimed by any of claims 23 to 25.

30. METHOD TO TREAT ANXIETY AND/OR INSOMNIA, characterized by giving a patient in need of said treatment daily quantity of 1 to 3000 mg of the pharmaceutical composition as claimed by claim 27.