HK1078780B - Pharmaceutical compositions comprising one or more steroids, one or more tetrahydrofolate components and vitamin b12 - Google Patents

Description

Pharmaceutical composition comprising one or more steroids, one or more tetrahydrofolate components and vitamin B12

Technical Field

The present invention relates to a kit comprising a plurality of oral dosage units for use in a method of hormonal contraception or hormone replacement therapy in a female mammal. The kit consists of at least ten dosage units comprising one or more steroids selected from the group consisting of estrogen and progestin, one or more tetrahydrofolate components, and vitamin B12.

Other aspects of the invention relate to a method of hormonal contraception and a method of hormone replacement therapy in a female mammal, said method comprising orally administering to the female mammal at least once daily one or more dosage units further comprising one or more tetrahydrofolate components and vitamin B12, in order to provide steroids in an amount effective to inhibit ovulation and/or to prevent or suppress symptoms of hypogonadism.

Background

Folate depletion is associated with sustained oral administration of hormonal preparations, particularly for hormonal contraception or hormone replacement therapy (Martindale, The Complete Drug Reference,healthcare series vol.111, edition date 3/2002). Some reports also mention reduced vitamin B12 levels in patients taking oral contraceptives (e.g., Martindale).

WO99/53910 describes a folic acid containing pharmaceutical composition comprising an oral contraceptive or hormone replacement component. The purpose of these compositions is to provide a method for providing folic acid to a patient suffering from or at increased risk of suffering from a folate-treatable disease. WO99/53910 states that correction of low folate levels in pregnant women requires a minimum of 2 months, while reserves can only be maintained for a few weeks. It is also mentioned that folic acid supplementation shortly before discontinuation of oral contraceptives or shortly after a positive pregnancy test may not be sufficient to provide optimal protection to a growing fetus. It is further stated that a reduction in folate levels in a subject taking an oral contraceptive poses an additional risk to those subjects who are pregnant within 3 to 6 months of discontinuation of the contraceptive.

As described in WO99/53910, the combination of folic acid with an oral contraceptive or a hormone replacement composition has the advantage of helping the user of an oral contraceptive or a hormone replacement composition to prevent folic acid deficiency.

However, folic acid, in combination with oral contraceptives and hormone replacement compositions, can mask the symptoms of vitamin B12 deficiency, such as megaloblastic anemia, and thus carry a serious health risk. The blood abnormalities seen with vitamin B12 deficiency can be treated with folic acid alone. However, neuropsychiatric abnormalities caused by vitamin B12 deficiency will not be corrected and may actually worsen. For example, folic acid administration to patients with megaloblastic anemia arising from folic acid deficiency will mask early symptoms, leading to neurological symptoms such as ataxia, paresthesia (combined systemic disease) in later stages.

Vitamin B12 deficiency is a multisystemic disease that varies clinically and is present in 0.4% of the total us population. Symptoms of vitamin B12 deficiency include severe anemia, manifested for example by a decrease in hematocrit or a decrease in hemoglobin, with megared blood cells, or neurological symptoms of peripheral neuropathy and/or ataxia. The blood abnormalities seen are caused by a deficiency of intracellular folate. Since folate is required for many of the essential enzymatic reactions in DNA and RNA synthesis and the form of folate (5-formyltetrahydrofolate) in serum must be metabolized to tetrahydrofolate by the vitamin B12-dependent enzyme methionine synthase in order to be available to RNA-and DNA-related enzymes.

The incidence of folate deficiency in the human population is unknown, but is believed to occur commonly in people with varying degrees of alcoholism, people with malabsorption or malnutrition, women using hormonal contraceptives, pregnant women, and some cancer patients. A common method of treating or preventing folate deficiency is oral folate. In order to alleviate or prevent the symptoms of folate deficiency, folic acid must be metabolized to a metabolically active form through a number of steps. After absorption, folic acid is reduced to dihydrofolic acid and then tetrahydrofolic acid (THF) by folate reductase and dihydrofolate reductase. Both enzymes require NADPH (nicotinic acid-dependent) as a cofactor. Serine then binds to pyridoxal-5' -phosphate to transfer the hydroxymethyl group to THF. As a result, 5, 10-methylenetetrahydrofolic acid and glycine were produced. This molecule is of great importance because it is a precursor of 5-methyltetrahydrofolate, which is metabolically active and involved in the metabolism of the hormone homocysteine, and also of methlynetetrahydrofolate (which is involved in purine synthesis). The methenyltetrahydrofolic acid also acts independently on the formation of the side chain of thymine constituting DNA. Studies have demonstrated that the oral bioavailability of folic acid varies widely. There are reports in the literature of poor intestinal folate uptake in individuals who respond normally to intramuscular injections. The metabolic process of orally administering folic acid to its active metabolites is known to be influenced by a variety of physiological, nutritional and pharmacological factors. In particular, the reduction of folate to THF is known to be hampered by external factors such as the use of hormonal contraceptives and certain drugs such as methotrexate, fluorouracil (5-flurouracil), sulfasalazine, diphenylhydantoin, trimethoprim, pyrimethamine and sulfonamides. Therefore, supplementation of folic acid to women using hormonal contraceptives has the disadvantages of (a) this approach is not sufficient to restore normal serum folate levels and (b) more importantly, the effect of such supplementation varies from individual to individual due to individual differences in folate metabolism.

Disclosure of Invention

The main object of the present invention is to achieve the benefits of folate supplementation for vitamin B12 deficient patients in hormonal contraceptive methods and hormone replacement therapy, avoiding the above-mentioned adverse consequences. The inventors have found that this object can be effectively and reliably achieved by co-administration of tetrahydrofolic acid and vitamin B12 in oral contraceptive methods or hormone replacement therapy.

Furthermore, in the method of the present invention, the prevention of folate deficiency is effectively and reliably achieved by administering a tetrahydrofolate selected from the group consisting of: (6S) -tetrahydrofolic acid, 5-methyl- (6S) -tetrahydrofolic acid, 5-formyl- (6S) -tetrahydrofolic acid, 10-formyl- (6R) -tetrahydrofolic acid, 5, 10-methylene- (6R) -tetrahydrofolic acid, 5, 10-methenyl- (6R) -tetrahydrofolic acid, 5-formimino- (6S) -tetrahydrofolic acid, pharmaceutically acceptable salts of these folic acids, and glutamyl derivatives. Unlike folic acid, the physiological effects of tetrahydrofolic acid are predictable and reliable because they are not affected by external factors such as, in particular, the concurrent administration of oral contraceptives.

Detailed Description

Accordingly, in one aspect the invention relates to a kit for use in a hormonal contraceptive method or hormone replacement therapy in a female mammal. The kit comprises at least 10 oral dosage units comprising at least 1 μ g of one or more steroids selected from estrogens and progestins; at least 0.1mg of one or more tetrahydrofolate components selected from the group consisting of: (6S) -tetrahydrofolic acid, 5-methyl- (6S) -tetrahydrofolic acid, 5-formyl- (6S) -tetrahydrofolic acid, 10-formyl- (6R) -tetrahydrofolic acid, 5, 10-methylene- (6R) -tetrahydrofolic acid, 5, 10-methenyl- (6R) -tetrahydrofolic acid, 5-formimino- (6S) -tetrahydrofolic acid, pharmaceutically acceptable salts of these folic acids, and glutamyl derivatives; and at least 0.1mg vitamin B12.

Throughout this document the term "folic acid" encompasses folic acid as well as salts of folic acid. Similarly, the term "tetrahydrofolic acid" refers to tetrahydrofolic acid as well as salts thereof. In a particularly preferred embodiment of the invention, the one or more tetrahydrofolic acid components are selected from the group consisting of 5-formyl-tetrahydrofolic acid (folinic acid), 5-methyl-tetrahydrofolic acid, and pharmaceutically acceptable salts and glutamyl derivatives of these acids. More preferably, the one or more tetrahydrofolate components are selected from the group consisting of folinic acid and pharmaceutically acceptable salts and glutamyl derivatives thereof. Most preferably, the tetrahydrofolate component is folinic acid.

Folinic acid (5-formyl-tetrahydrofolic acid or leucovorin) has long been used in therapeutics for several diseases. Examples include rescue of methotrexate chemotherapy toxicity and synergy with fluorouracil to treat different cancers. It is also used for treating acute anemia. High doses (e.g., 50 mg/day) of 5-methyl-tetrahydrofolic acid have patented for the treatment of depression and other neurological diseases (EP 382019 and EP388827, 1990 to Le Grazie; and EP482493, 1992 to Le Greca).

The term vitamin B12 is used to denote compounds of the cobalt corrinoid family, in particular the cobalamin group. The most common of this group of compounds is cyanocobalamin, and therefore the term vitamin B12 is sometimes used to denote cyanocobalamin. In the present description, the term vitamin B12 should be interpreted in its broadest sense to include all cobalt corrinoids of the cobalamin group, which specifically includes cyanocobalamin, hydroxocobalamin, methylcobalamin and nitrocobalamin. The present invention includes the use of vitamin B12 itself and a precursor of vitamin B12 capable of releasing vitamin B12 in vivo for use according to the present method, and vitamin B12 in vivo metabolites (e.g. conjugates with polypeptides) that exhibit the same in vivo efficacy as vitamin B12, particularly in terms of alleviating the symptoms of vitamin B12 deficiency.

Vitamin B12 deficiency may occur in unhealthy individuals with intestinal absorption problems (malabsorption) and several other conditions. It may also result from the use of certain drugs. And vitamin B12 deficiency is not common in strict vegetarians and vegetarians.

Examples of estrogens suitable for use in the dosage units of this invention include ethinyl estradiol, methyl estrol ether, quinestranol, estradiol, estrone, estrane (estran), estriol, conjugated equine estrogens and prodrugs thereof which release similar estrogens in vivo when used in the methods of this invention.

Progestins that may be suitable for use in the dosage units of the present invention include levonorgestrel, norgestimate, norethindrone, dydrogesterone, drospirenone, 3 β -hydroxydesogestrel, 3-ketodesogestrel (etonogestrel), 17-deacetyl norgestimate, 19-norgestrel, acetoxypregnenolone, allylestrenol, anagestrel, chlormadrogesterone, cyproterone, demegestone, desogestrel, dienogest, dihydroprogesterone, demegestone, ethisterone, norethindrone diacetate, fluogesterone, gestodene, trienone, medroxyprogesterone, hydroxyprogesterone, lynestrenol (, lynoenol), medroxyprogesterone, megestrol, norelgestromone, norethindrone (═ norethindrone), norethindrone, norgestrel (including d-norgestrel and dl-norgestrel), Norgestenone, nornethisterone, progesterone, quingestrol, (17 α) -17-hydroxy-11-methylene-19-norpregn-4, 15-dien-20-yn-3-one, tibolone, trimegestone, acetophenone diglycol, nestorone, promeggestone, 17-hydroxyprogesterone esters, 19-nor-17 hydroxyprogesterone, 17 α -ethynyl-testosterone, 17 α -ethynyl-19-nor-testosterone, d-17 β -acetoxy-13 β -ethyl-17 α -ethynyl-gon-4-en-3-one oxime and precursors of these compounds. Preferred progestogens for use in the progestogenic phase are selected from the group consisting of levonorgestrel, norgestimate, norethindrone, drospirenone, dydrogesterone and prodrugs thereof which are capable of releasing similar progestogens in vivo when used in the method of the present invention.

The kit of the invention preferably comprises at least 10 oral dosage units comprising from 2 μ g to 30mg of one or more steroids, from 0.2 to 15mg of one or more tetrahydrofolate components and from 0.2 to 20mg of vitamin B12. Examples of suitable oral dosage units include tablets and capsules. They may contain excipients such as binders (e.g. hydroxypropylmethylcellulose, polyvinylpyrrolidone, other cellulosic materials and starch), diluents (e.g. lactose and other sugars, starch, dicalcium phosphate and cellulosic materials), disintegrants (e.g. starch polymers and cellulosic materials) and lubricants (e.g. stearates and talc).

The kits of the present invention are suitably in the form of a container or strip containing a plurality of oral dosage units. In the case of a strip, the daily (or other periodic) doses are arranged in the appropriate order for administration. In a preferred embodiment, the present invention provides a kit for continuous daily administration, the kit consisting of a pharmaceutical pack containing a plurality of dosage units.

The kit of the invention is suitable for different oral contraceptive methods. One well-known oral contraceptive regimen uses so-called monophasic preparations containing a fixed amount of estrogen and progestin throughout the administration cycle. The newer two-or triphasic formulations have different levels of estrogen and progestin; typically contain relatively constant levels of estrogen and a stepwise increase of progestin throughout the administration period. Mono-, di-, and triphasic contraceptives are commonly referred to as compound contraceptives.

Common to virtually all combined contraceptives is that they are based on a regimen with a 7-day rest period during which withdrawal bleeding occurs, mimicking the symptoms of normal menstruation, without the need for medication. Thus, hormone was taken for 21 days but the offspring were taken for 7 days without hormone for the rest period.

As an alternative to the above-mentioned contraceptive methods, so-called sequential methods have been proposed. A typical sequential contraceptive regimen comprises two phases, one during which estrogen is administered alone and the progestin is not administered, and another during which a combination of estrogen and progestin is administered. The earliest sequential regimens, like the above-described combined contraceptive regimen, also had a 7 day rest period with no dosing. More recently, sequential methods have been proposed which do not include such a non-administration (or placebo) period, i.e. the estrogen is administered during the entire administration period and the progestogen is administered only during part of the cycle. WO95/17895(Ehrlich et al) describes such an uninterrupted sequential process.

Another example of an oral contraceptive method with uninterrupted continuous administration is the so-called continuous combined method, which combines the administration of an estrogen and a progestogen during more than 28 days, in particular more than 2 months. Yet another example of an oral contraceptive method with uninterrupted continuous administration is the progestogen-only method, which continuously takes progestogen without estrogen for more than 28 days, especially for more than 2 months.

When the kit of the invention is used in a contraceptive method having an intermittent period of non-steroid administration, it is preferred to continue administration of the tetrahydrofolate component and vitamin B12 (and other optional vitamins, such as vitamin B6) during the intermittent period. Thus, the kit preferably comprises one or more dosage units, preferably 3 to 8 dosage units, comprising one or more tetrahydrofolate components and vitamin B12 in the amounts described herein, but which are substantially free of progestogen or estrogen.

It was found that the continuous, uninterrupted administration of one or more tetrahydrofolate components and vitamin B12 is more effective in preventing and treating deficiencies of one or both of these components than a regimen of intermittent administration for several days during each (4 week) cycle. Thus, in a preferred embodiment, the method essentially comprises administering one or more tetrahydrofolate components and vitamin B12 (and other optional vitamins such as vitamin B6) sequentially over a time interval of at least 40 days, preferably at least 90 days. In another preferred embodiment, the method comprises an intermittent period of 3-8 days during which one or more tetrahydrofolate components and vitamin B12 are administered without estrogen or progestin. As mentioned above, it is advantageous to administer the tetrahydrofolate component and vitamin B12 continuously and uninterruptedly, even in cases where a contraceptive regimen (e.g. in a combined contraceptive regimen) requires that no estrogen or progestin be administered for a particular period.

Contraceptive regimens without an interval of no administration (or administration of placebo) are more likely to result in folate depletion than regimens with such an interval. Thus, the advantages of the present invention are highlighted in oral contraceptive methods that do not have a regular, e.g., 4 week, non-dosing interval. Similarly, the present invention provides important benefits for hormone replacement therapy using continuous uninterrupted administration of steroids, particularly estrogens in combination with progestins. Accordingly, in a preferred embodiment, all dosage units in the kit of the invention contain the one or more steroids, the one or more tetrahydrofolate components and vitamin B12 in the stated amounts, i.e. the kit of the invention does not contain any placebo.

In another aspect, the invention relates to a hormonal contraceptive method comprising orally administering one or more steroid containing dosage units to a female mammal at least once daily to provide steroids in an amount effective to inhibit ovulation, and wherein the dosage units further contain at least 0.1mg of one or more tetrahydrofolate components and at least 0.1mg vitamin B12.

Yet another aspect of the invention relates to hormone replacement therapy in a female mammal during the peri-menopausal, or post-menopausal period, which comprises orally administering to the female at least once daily one or more steroid containing dosage units thereby providing an effective amount of steroid to prevent or inhibit the symptoms of hypogonadism. Wherein the dosage unit further comprises at least 0.1mg of one or more tetrahydrofolate components and at least 0.1mg of vitamin B12.

The steroid used in the above method is preferably selected from the group consisting of estrogens and progestins. Examples of suitable estrogens and progestins are described above. Preferably, the estrogen is selected from the group consisting of: ethinyl estradiol, 17 β -estradiol, estetrol and precursors thereof. The progestogen is preferably selected from the group consisting of: levonorgestrel, norgestimate, norethindrone, drospirenone, dydrogesterone, trimegestone, and precursors thereof.

Because the ethinyl estradiol has a remarkable inhibiting effect on the concentration of folic acid in serum, the advantages of the invention are highlighted when the ethinyl estradiol is taken in combination with tetrahydrofolic acid and vitamin B12. Ethinyl estradiol is used in almost all oral contraceptives sold to date. In a particularly preferred embodiment of the invention, the dosage unit contains from 3 to 40 μ g, preferably from 10 to 30 μ g, of ethinyl estradiol.

The main purpose of co-adding the tetrahydrofolate component and vitamin B12 is to prevent or treat deficiencies in either of these vitamins. The cause of folate deficiency is generally the long-term use of the steroids mentioned above. Thus, the dosage unit is preferably administered to provide a therapeutically effective amount of one or more folic acid components to prevent or treat folate deficiency. The method of the present invention is particularly effective for preventing or inhibiting folate deficiency caused by long-term use of the above steroids. Preferably, vitamin B12 is also administered to provide a therapeutically effective amount of vitamin B12 to prevent or treat vitamin B12 deficiency.

Vitamin deficiency is usually diagnosed by measuring serum levels. Normal serum vitamin B12 levels were 211-911pg/ml, with levels below 100pg/ml determined to be indicative of a clinically significant deficiency. However, serum vitamin B12 levels are a relatively insensitive method for diagnosing vitamin B12 deficiencies, since only 50% of patients clinically diagnosed with vitamin B12 deficiency have levels below 100pg/ml, 40% are 100pg/ml, and at least 5-10% are between 200pg/ml and 300 g. The diagnosis is further complicated by the fact that 2.5% of subjects without any symptoms of vitamin B12 deficiency have low serum vitamin B12 levels.

Normal serum folate levels are about 2.8ng/ml, with levels below 2.8ng/ml indicating a potential for clinically significant deficiency. However, as with vitamin B12 serum levels, serum folate levels are a relatively insensitive approach, as only 50-75% of patients with folate deficiency have serum folate levels below 2.8 ng/ml. Advances in Homocysteine (HC), alanine buthionine (CT), methylmalonic acid (MMA) and 2-methylcitric acid (2-MCA) sensitive serum metabolite analysis enabled the study of the relationship between metabolite levels and vitamin deficiency. (Stabler et al, (1987) anal. biochem.162: 185-196; Stabler et al, (1986) J.Clin.invest.77: 1606-1612; Stabler et al, (1988) J.Clin.invest.81: 466-474).

Elevated serum HC and MMA levels were found to be clinically useful in assays for functional intracellular vitamin B12 and folate Deficiency, with elevated HC levels being associated with vitamin B12 and folate Deficiency, and elevated MMA levels being associated with vitamin B12 Deficiency (Allen et al, (1990) am. J. Hematol.34: 90-98; Lindenbaum et al, (1990) am. J. Hematol.34: 99-107; Lindenbaum et al, (1988) N. Engl. J. Med.318: 1720-1728; Beck (1991) in Neuropychiatric Consequence of Cobalmin Deficiency, Mosby Yearrk-36: 33-56; Moelby et al, J Intern-228: 373, and 1204; Uelsum and Refsumm (1989) J. ocean J. Cleark. 36: Med.68; Geelb.501: P.103: P. J. Geelr.501; Soelsu et al, J. 1988). Elevated CT levels can be seen in both deficiencies, and 2-MCA levels are elevated in vitamin B12 deficiency.

In a preferred embodiment of the method of the invention, a therapeutically effective amount of one or more tetrahydrofolate components and vitamin B12, which significantly reduces serum levels of at least one of homocysteine, thiolyalaninate, methylmalonic acid and/or 2-methylcitric acid, is administered to a female animal having elevated serum levels of one or more of these substances. In a particularly preferred embodiment, the method of the invention restores all of the above to normal serum levels.

The method of the invention preferably comprises a dosing regimen that provides the female with at least 18 consecutive daily doses for:

from 2 μ g to 30mg of one or more steroids;

from 0.2 to 15mg of one or more tetrahydrofolate components; and

from 0.2 to 20mg vitamin B12.

In another preferred embodiment, the method of the invention comprises a regimen providing to the female an at least 18 consecutive daily dosage of days comprising an estrogen in an amount equivalent to 3 to 40 μ g of ethinyl estradiol and/or a progestin in an amount equivalent to 30 to 750 μ g of levonorgestrel.

As previously mentioned, the advantages of the present invention are highlighted in particular in the context of hormone replacement therapy or oral contraceptive methods with continuous uninterrupted administration of one or more steroids. Thus, the method of the invention preferably consists essentially of administering steroid containing dosage units continuously over a time interval of at least 40 days, preferably at least 90 days.

The term "continuous" when used in reference to the administration of one or more active ingredients means that the one or more active ingredients are administered at relatively regular intervals and without (therapeutically) significant interruptions. Naturally, short-term interruptions may be present which do not affect the overall effectiveness of the method of the invention, and in fact such deviations are encompassed by the invention. In a preferred embodiment, a dosage regimen is considered continuous if, more mathematically, the interval between two consecutive doses is no longer than 3.5 times its average dosing interval. Still more preferably, the above-mentioned longest interval is not longer than 2.5 times the average interval.

Similar to vitamin B12 deficiency, vitamin B6 (pyridoxine) deficiency also leads to hematologic and neuropsychiatric abnormalities. Vitamin B6 is required for the first step in heme synthesis and plays an important role in transamination reactions in amino acid metabolism, in decarboxylation and in the synthesis of neuroactive amines such as histamine, tyramine, serotonin and γ -aminobutyric acid. Clinical symptoms of vitamin B6 deficiency include microcytic hypohemoglobin anemia, significant skin lesions such as dermatitis and acrodynia, muscle weakness, and a variety of neuropsychiatric abnormalities including stress increases, convulsions, depression and confusion (Newberne and Conner (1989), Clinical Biochemistry of Clinical analytics Animals, Academic Press, San Diego, pp.796-834).

The human body usually contains 40-150mg of vitamin B6. It is administered at a daily dose of 1-2 mg. It is generally recommended to ingest higher amounts of vitamin B6 during pregnancy. A normal diet can meet this elevated demand, but dietary analysis of 26 pregnant women in the united states showed that only one pregnant woman ingested more than 2.5mg per day of vitamin B6. Studies conducted in the United states and Sweden (Hamfelt and Tuveno, Clin chem Acta (1972) 41: 287 and Lumeng et al, Am J Clin Nutr (1976) 29: 1376-1383) suggest that pregnant women are eligible to consume about 10mg of vitamin B6 per day. It is believed that the increased demand of vitamin B6 may be explained by the important role of this vitamin in fetal development. This important effect is evidenced by the finding that the concentration of vitamin B6 in blood taken from the umbilical cord of a pregnant human woman is higher than the concentration of vitamin B6 in the blood of the mother. Also, experimental studies in rats (Davis et al, Science (1970) 169: 1329) have shown that vitamin B6 deficiency can lead to congenital malformations.

Studies have also shown that (Martindale) oral contraceptives can lead to vitamin B6 deficiency in some users. It is therefore apparent that users of oral contraceptives are at risk of developing vitamin B6 deficiencies. The risk of vitamin B6 deficiency is even more pronounced, especially in women who become pregnant shortly after discontinuation of oral contraceptives, especially because it takes a long time for the vitamin B6 serum levels to return to normal.

Thus, in a particularly preferred embodiment of the invention, the dosage unit further comprises at least 3mg vitamin B6, more preferably 5 to 250mg vitamin B6. The term "vitamin B6" as used throughout this document includes any ingredient that is capable of being converted in vivo to pyridoxal, pyridoxal phosphate or a pyridoxal salt. Vitamin B6 component which is converted in vivo to pyridoxal, pyridoxal phosphate or a pyridoxal salt in at least 10 mol% within 24 hours after administration is particularly useful. Pyridoxal phosphate and pyridoxamine phosphate are biologically active forms of vitamin B6 as coenzymes for more than 100 biological responses in living human or animal cells.

It is known that the diagnosis of folate, vitamin B12 and vitamin B6 deficiencies is usually based on concentrations in serum/plasma. It is generally accepted that adult humans lack folate at serum concentrations below 2.8 ng/ml. Similarly, vitamin B12 and vitamin B6 were diagnosed as deficient if the serum concentration of vitamin B12 was less than 211pg/ml and the plasma concentration of vitamin B6 (measured as pyridoxal-5-phosphate) was less than 5 ng/ml. These baseline values have been published by the clinical laboratory at the university of california, san diego. The methods proposed by these clinical laboratories to measure levels of folate, vitamin B12 and vitamin B6 are:

folic acid: chemiluminescence competition method, CPTCode82746

Vitamin B12: chemiluminescence competition method, CPTCode82746

Vitamin B6: radioimmunoassay, CPTCode84207

The invention is further illustrated by the following examples.

Examples

Example 1

A contraceptive kit in the form of a strip comprising 28 tablets each weighing 0.25 grams was prepared. Of the 28 tablets, 21 contained composition a and 7 contained composition B. Compositions a and B are shown below:

composition A composition B

Ethinyl estradiol 30 mug

Levonorgestrel 150 μ g

Folic acid 0.5mg

Vitamin B121 mg 1mg

Vitamin B650 mg 50mg

Balance of excipient

Example 2

A kit in the form of a strip containing 28 tablets for use in a sequential contraceptive method is prepared. The kit contains 14 tablets of composition a and 14 tablets of composition B. Compositions a and B are shown below:

composition A composition B

30 mug of ethinyl estradiol and 30 mug

Levonorgestrel 150 μ g

Folic acid 0.5mg

Vitamin B121 mg 1mg

Vitamin B650 mg 50mg

Balance of excipient

Example 3

40 women were randomized into 2 groups of 20 women each. One group used the contraceptive kit described in example 1 over a period of 4 months. For the same period of time, the same kit was used for the other group, but the tablets in the kit did not contain folic acid or vitamin B12 or vitamin B6.

Serum concentrations of folic acid, vitamin B12 and vitamin B6 were determined before and after the start of the trial using the method described in 2002 by the aforementioned clinical laboratory of the university of California, san Diego. It was found that the serum concentration of the above substances did not change significantly during the experiment in the group receiving oral contraceptives without folic acid, vitamin B12 or vitamin B6. However, a significant increase in folate, vitamin B12 and/or vitamin B6 levels was observed in a majority of women in the other group.

Some women were found to be deficient in folic acid, vitamin B12 and/or vitamin B6 before the start of the experiment. Women suffering from this deficiency and receiving oral contraceptives with increased levels of folic acid, vitamin B12 and vitamin B6 were found to no longer lack any of the 3 above at the end of the experiment.

Example 4

The experiment of example 4 was repeated with the kit described in example 2 instead of the kit described in example 1.

During the experiment, it was found that the serum levels of folic acid, vitamin B12 and vitamin B6 did not change significantly in a group of women receiving an oral contraceptive that did not contain folic acid, vitamin B12 or vitamin B6. At the end of the experiment, a significant increase in levels of folate, vitamin B12 and/or vitamin B6 was found in a majority of women in the other group.

Women who were found to be deficient in folic acid, vitamin B12 and/or vitamin B6 prior to the start of the experiment and who received oral contraceptives supplemented with folic acid, vitamin B12 and vitamin B6 were not deficient in any of the three substances described above after the end of the experiment.

Claims (8)

1. A kit for use in a hormonal contraceptive method or hormone replacement therapy in a mammalian female, said kit comprising at least 10 oral dosage units comprising:

a)10-40 μ g of ethinyl estradiol;

b)0.2-15mg of one or more tetrahydrofolate components selected from the group consisting of: (6S) -tetrahydrofolic acid, 5-methyl- (6S) -tetrahydrofolic acid, 5-formyl- (6S) -tetrahydrofolic acid, 10-formyl- (6R) -tetrahydrofolic acid, 5, 10-methylene- (6R) -tetrahydrofolic acid, 5, 10-methenyl- (6R) -tetrahydrofolic acid, 5-formimino- (6S) -tetrahydrofolic acid, pharmaceutically acceptable salts of these tetrahydrofolic acids, and glutamyl derivatives of these tetrahydrofolic acids; and

c)0.2-20mg of vitamin B12.

2. The kit of claim 1, wherein the kit comprises one or more dosage units comprising one or more of said tetrahydrofolate components and vitamin B12 in said amounts, but no progestin or estrogen.

3. Kit according to claim 2, wherein the kit comprises 3 to 8 dosage units containing one or more of said amounts of tetrahydrofolate component and vitamin B12, but no progestin or estrogen.

4. Kit according to any one of claims 1 to 3, wherein the one or more tetrahydrofolate components are selected from the group consisting of 5-formyl-tetrahydrofolic acid, 5-methyl-tetrahydrofolic acid, and pharmaceutically acceptable salts of these acids and glutamyl derivatives of these folic acids.

5. The kit of claim 4, wherein said one or more tetrahydrofolate components are selected from the group consisting of 5-formyl- (6S) -tetrahydrofolic acid, 5-methyl-tetrahydrofolic acid, and pharmaceutically acceptable salts of these tetrahydrofolic acids and glutamyl derivatives of these tetrahydrofolic acids.

6. Kit according to any one of claims 1 to 3, wherein the dosage unit comprises from 10 to 30 μ g of ethinyl estradiol.

7. The kit of any one of claims 1-3 and 5, wherein the one or more tetrahydrofolate components are selected from the group consisting of 5-formyl- (6S) -tetrahydrofolic acid, pharmaceutically acceptable salts of 5-formyl- (6S) -tetrahydrofolic acid, and glutamyl derivatives of 5-formyl- (6S) -tetrahydrofolic acid.

8. The kit of any one of claims 1-3 and 5, wherein said dosage unit contains at least 3mg of vitamin B6.