Medrogestone

Last updated
Medrogestone
Medrogestone.svg
Clinical data
Trade names Colprone, others
Other namesMetrogestone; Medrogesterone; AY-62022, NSC-123018, R-13615; 6,17α-Dimethyl-6-dehydroprogesterone; 6,17α-Dimethyl-4,6-pregnadiene-3,20-dione
Pregnancy
category
  • X
Routes of
administration
By mouth
Drug class Progestogen; Progestin
ATC code
Legal status
Legal status
  • In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability Nearly 100% [1] [2]
Protein binding 95%: Albumin (90%), CBG (3%), SHBG (2%) [2]
Metabolism Hepatic (hydroxylation) [1]
Elimination half-life 35–36 hours [3] [4] [5]
Identifiers
  • (8R,9S,10R,13S,14S,17S)-17-acetyl-6,10,13,17-tetramethyl-2,8,9,11,12,14,15,16-octahydro-1H-cyclopenta[a]phenanthren-3-one
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
CompTox Dashboard (EPA)
ECHA InfoCard 100.012.323 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C23H32O2
Molar mass 340.507 g·mol−1
3D model (JSmol)
  • O=C4\C=C3\C(=C/[C@@H]1[C@H](CC[C@@]2([C@@](C(=O)C)(CC[C@@H]12)C)C)[C@@]3(C)CC4)C
  • InChI=1S/C23H32O2/c1-14-12-17-18(21(3)9-6-16(25)13-20(14)21)7-11-23(5)19(17)8-10-22(23,4)15(2)24/h12-13,17-19H,6-11H2,1-5H3/t17-,18+,19+,21-,22-,23+/m1/s1
  • Key:HCFSGRMEEXUOSS-JXEXPEPMSA-N

Medrogestone, sold under the brand name Colprone among others, is a progestin medication which has been used in menopausal hormone therapy and in the treatment of gynecological disorders. [6] [2] It is available both alone and in combination with an estrogen. [7] It is taken by mouth. [2] [8]

Contents

Medrogestone is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. [2] It has weak antiandrogenic, glucocorticoid, and antimineralocorticoid activity and no other important hormonal activity. [2] [1] [9] [10] Due to its progestogenic activity, medrogestone has antigonadotropic effects. [1] [2]

Medrogestone was described as early as 1963 and was introduced for medical use by at least 1966. [11] [12] [9] It has mostly been discontinued and remains available only in a few countries. [13] [7]

Medical uses

In the past, medrogestone was used in the treatment of endometrial cancer and in some regimens for breast cancer, and, in men, for benign prostatic hyperplasia. It still finds use in the treatment of amenorrhea [14] and as the progestin component in certain forms of menopausal hormone therapy. [15]

Cyclic treatment with low-dose (10 mg/day) medrogestone has been found to be effective in the treatment of fibrocystic breast changes and associated mastodynia (breast pain). [16]

Medrogestone is used as a form of progestogen-only birth control, although it is not specifically licensed as such. [17]

Contraindications

Intrahepatic cholestasis of pregnancy (acute or in history), vaginal bleeding of unknown origin, and severe diseases of the liver such as tumors are absolute contraindications for medrogestone, as are thrombotic events such as thrombophlebitis or stroke. [18]

Medrogestone is contraindicated during pregnancy because progestogens are associated with risks for the fetus in animals and humans. [19]

It is not known whether medrogestone passes into breast milk, but it is to be expected given its lipophilicity and studies with structurally related progestins. [19]

Side effects

Medrogestone seldom produces side effects, all of which are typical of progestogens. They include nausea, depression. [18]

Overdose

The acute toxicity of the drug is low. Overdose causes only harmless side effects such as nausea and vaginal bleeding. [19] The LD50 has been found to range between 500 mg/kg in dogs and over 3000 mg/kg in rats. Chronic toxicity has been examined in animals, but nothing but the typical adverse effects of progestogens, and reduction of prostatic weight in rhesus monkeys, have been found. Accidental intake of the drug, including in children, is normally not dangerous. Intake of extremely large doses, or intake by patients with epilepsy or impaired kidney function, can result in central nervous cramping. [18]

Interactions

Enzyme inducers such as barbiturates, phenylbutazone, phenytoin, ampicillin or tetracyclines are expected to reduce plasma concentrations of medrogestone, but no systematic research has been done. [19]

Pharmacology

Pharmacodynamics

Medrogestone is described as a pure progestogen similar in profile to progesterone. [9] [20] In contrast to progesterone however, medrogestone is more potent and is orally active. [9] There is reportedly no information available on the receptor binding of medrogestone at the various steroid hormone receptors. [2] However, based on animal research (e.g., the Clauberg test and other assays), medrogestone appears to be a potent progestogen, devoid of androgenic, estrogenic, and glucocorticoid activity, but with weak antiandrogenic and very weak antimineralocorticoid activity. [9] Accordingly, no evidence of androgenic or glucocorticoid activity, including effects on the estrogen-induced increase in triglycerides and HDL cholesterol and adrenal suppression, were observed in clinical studies. [2] [21] However, in a very high-dosage (100 mg/day for 6 months) study of medrogestone for benign prostatic hyperplasia, a hyperglycemic effect and changes in plasma cortisol levels were observed and considered likely to be secondary to glucocorticoid activity, and decreased sodium levels were also observed and attributed to antimineralocorticoid activity. [10] In any case, under normal circumstances (i.e., at typical clinical dosages), medrogestone is described as a progestogen and antigonadotropin and weak antiandrogen in humans without other clinically relevant activity. [1] [2]

Medrogestone has been found to be an inhibitor of 3β-hydroxysteroid dehydrogenase/Δ5-4 isomerase in vitro , preventing conversion of pregnenolone to progesterone and 17α-hydroxypregnenolone to 17α-hydroxyprogesterone in rat testis preparations, and inhibits the biosynthesis of testosterone in vivo in rats. [22] [23] [24] In addition, similarly to progesterone, medrogestone can inhibit 5α-reductase in vitro in microsomal preparations of skin and prostate. [25] Although their clinical relevance is uncertain, these actions of medrogestone could contribute to its weak antiandrogen activity. [26]

Pharmacokinetics

Upon oral administration, medrogestone is rapidly absorbed, and the bioavailability is nearly 100%. [1] [2] After ingestion of a 10 mg dose of medrogestone, peak circulating concentrations (Cmax) of 10–15 ng/mL are achieved. [2] The distribution and elimination half-lives of medrogestone are 4 hours and 35–36 hours, respectively. [2] [3] [4] The drug is largely bound (90%) to albumin, and to only small extents to corticosteroid-binding globulin (3%) and sex hormone-binding globulin (2%). [2] The metabolism of medrogestone is most importantly by hydroxylation. [1] [2]

Chemistry

Medrogestone, also known as 6,17α-dimethyl-6-dehydroprogesterone or as 6,17α-dimethyl-4,6-pregnadiene-3,20-dione, is a synthetic pregnane steroid and a derivative of progesterone. It is structurally related to the 17α-hydroxyprogesterone derivatives megestrol acetate and medroxyprogesterone acetate. [1] [2] Medrogestone itself is not a 17α-hydroxyprogesterone derivative and is instead a derivative of 17α-methylprogesterone. [1] [2] This is because it features a methyl group at the C17α position instead of a hydroxy or acetoxy group. [1] [2] In addition to its C17α methyl group, medrogestone possesses a methyl group at the C6 position and a double bond between the C6 and C7 positions. [1] The only structural difference between medrogestone and megestrol acetate is the replacement of the C17α acetoxy group with a methyl group. [11] [13] [7]

Synthesis

The oral activity of 17α-methylprogesterone has already been alluded to. This compound, which may well owe this property to the inhibition of metabolism in a manner analogous to synthetic androgens and estrogens, is not sufficiently potent in its own right to constitute a useful drug. Incorporation of known potentiating modifications yields the commercially available oral progestin medrogestone (4).

The preparation of the 6-methyl-16-dehydropregnenolone acetate (1) precursor is covered here.

Medrogestone synthesis. Medrogestone synthesis.svg
Medrogestone synthesis.

Reduction of the conjugated 16,17 double bond of 6-methyl-16-dehydropregnenolone acetate by means of lithium in liquid ammonia leads initially to the 17 enolate ion; this is alkylated in situ with methyl iodide. The now-familiar steric control asserts itself to afford the 17α-methyl compound,.

The acetate group is lost as a side reaction. In an interesting modification on the usual scheme, (3) is treated with aluminum isopropoxide and a ketone (Oppenauer conditions) as well as chloranil in a single reaction; the 4,6-diene, (medrogesterone), is obtained directly from this step.

History

Medrogestone was first described as early as 1963 and appears to have been marketed since at least 1966. [11] [12] [9]

Society and culture

Generic names

Medrogestone is the generic name of the drug and its INN, USAN, and BAN. [11] [13] [6] [7] It is also known by its developmental code names AY-62022, NSC-123018, and R-13615. [11] [13] [6] [7]

Brand names

Medrogestone is or has been marketed under the brand names Ayerluton, Colpro, Colpron, Colprone, Etogyn, Prothil, and, in combination with conjugated estrogens, Presomen. [11] [13] [7]

Availability

Medrogestone has been marketed in the United States [9] and Canada and widely throughout Europe, as well as in Argentina, Hong Kong, and other countries. [13] However, it is no longer available in the United States [28] or many other countries, and is reported to remain marketed only in a few countries including France, Germany, Tunisia, and Egypt. [7]

Related Research Articles

Progestogen Steroid hormone that activates the progesterone receptor

Progestogens, also sometimes written progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestogen in the body. The progestogens are named for their function in maintaining pregnancy, although they are also present at other phases of the estrous and menstrual cycles.

<span class="mw-page-title-main">Progestogen (medication)</span> Medication producing effects similar to progesterone

A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a synthetic progestogen. Progestogens are used most commonly in hormonal birth control and menopausal hormone therapy. They can also be used in the treatment of gynecological conditions, to support fertility and pregnancy, to lower sex hormone levels for various purposes, and for other indications. Progestogens are used alone or in combination with estrogens. They are available in a wide variety of formulations and for use by many different routes of administration. Examples of progestogens include natural or bioidentical progesterone as well as progestins such as medroxyprogesterone acetate and norethisterone.

<span class="mw-page-title-main">Norethisterone acetate</span> Chemical compound

Norethisterone acetate (NETA), also known as norethindrone acetate and sold under the brand name Primolut-Nor among others, is a progestin medication which is used in birth control pills, menopausal hormone therapy, and for the treatment of gynecological disorders. The medication available in low-dose and high-dose formulations and is used alone or in combination with an estrogen. It is ingested orally.

<span class="mw-page-title-main">Norgestimate</span>

Norgestimate, sold under the brand names Ortho Tri-Cyclen and Previfem among others, is a progestin medication which is used in birth control pills for women and in menopausal hormone therapy. The medication is available in combination with an estrogen and is not available alone. It is taken by mouth.

<span class="mw-page-title-main">Norethisterone</span> Progestin medication

Norethisterone, also known as norethindrone and sold under many brand names, is a progestin medication used in birth control pills, menopausal hormone therapy, and for the treatment of gynecological disorders. The medication is available in both low-dose and high-dose formulations and both alone and in combination with an estrogen. It is used by mouth or, as norethisterone enanthate, by injection into muscle.

<span class="mw-page-title-main">Gestonorone caproate</span> Chemical compound

Gestonorone caproate, also known as gestronol hexanoate or norhydroxyprogesterone caproate and sold under the brand names Depostat and Primostat, is a progestin medication which is used in the treatment of enlarged prostate and cancer of the endometrium. It is given by injection into muscle typically once a week.

<span class="mw-page-title-main">Ethisterone</span> Chemical compound

Ethisterone, also known as ethinyltestosterone, pregneninolone, and anhydrohydroxyprogesterone and formerly sold under the brand names Proluton C and Pranone among others, is a progestin medication which was used in the treatment of gynecological disorders but is now no longer available. It was used alone and was not formulated in combination with an estrogen. The medication is taken by mouth.

<span class="mw-page-title-main">Hydroxyprogesterone caproate</span> Medication

Hydroxyprogesterone caproate (OHPC), sold under the brand names Proluton and Makena among others, is a progestin medication which is used to prevent preterm birth in pregnant women with a history of the condition and to treat gynecological disorders. It has also been formulated in combination with estrogens for various indications and as a form of long-lasting injectable birth control. It is not used by mouth and is instead given by injection into muscle or fat, typically once per week to once per month depending on the indication.

<span class="mw-page-title-main">Dienogest</span> Chemical compound

Dienogest, sold under the brand name Visanne among others, is a progestin medication which is used in birth control pills and in the treatment of endometriosis. It is also used in menopausal hormone therapy and to treat heavy periods. Dienogest is available both alone and in combination with estrogens. It is taken by mouth.

<span class="mw-page-title-main">Chlormadinone acetate</span> Chemical compound

Chlormadinone acetate (CMA), sold under the brand names Belara, Gynorelle, Lutéran, and Prostal among others, is a progestin and antiandrogen medication which is used in birth control pills to prevent pregnancy, as a component of menopausal hormone therapy, in the treatment of gynecological disorders, and in the treatment of androgen-dependent conditions like enlarged prostate and prostate cancer in men and acne and hirsutism in women. It is available both at a low dose in combination with an estrogen in birth control pills and, in a few countries like France and Japan, at low, moderate, and high doses alone for various indications. It is taken by mouth.

Dimethisterone Chemical compound

Dimethisterone, formerly sold under the brand names Lutagan and Secrosteron among others, is a progestin medication which was used in birth control pills and in the treatment of gynecological disorders but is now no longer available. It was used both alone and in combination with an estrogen. It is taken by mouth.

Promegestone Chemical compound

Promegestone, sold under the brand name Surgestone, is a progestin medication which is used in menopausal hormone therapy and in the treatment of gynecological disorders. It is taken by mouth.

Allylestrenol Chemical compound

Allylestrenol, sold under the brand names Gestanin and Turinal among others, is a progestin medication which is used to treat recurrent and threatened miscarriage and to prevent premature labor in pregnant women. However, except in the case of proven progesterone deficiency, its use for such purposes is no longer recommended. It is also used in Japan to treat benign prostatic hyperplasia (BPH) in men. The medication is used alone and is not formulated in combination with an estrogen. It is taken by mouth.

Trimegestone Chemical compound

Trimegestone, sold under the brand names Ondeva and Totelle among others, is a progestin medication which is used in menopausal hormone therapy and in the prevention of postmenopausal osteoporosis. It was also under development for use in birth control pills to prevent pregnancy, but ultimately was not marketed for this purpose. The medication is available alone or in combination with an estrogen. It is taken by mouth.

Nomegestrol acetate Chemical compound

Nomegestrol acetate (NOMAC), sold under the brand names Lutenyl and Zoely among others, is a progestin medication which is used in birth control pills, menopausal hormone therapy, and for the treatment of gynecological disorders. It is available both alone and in combination with an estrogen. NOMAC is taken by mouth. A birth control implant for placement under the skin was also developed but ultimately was not marketed.

<span class="mw-page-title-main">Segesterone acetate</span>

Segesterone acetate (SGA), sold under the brand names Nestorone, Elcometrine, and Annovera, is a progestin medication which is used in birth control and in the treatment of endometriosis in the United States, Brazil, and other South American countries. It is available both alone and in combination with an estrogen. It is not effective by mouth and must be given by other routes, most typically as a vaginal ring or implant that is placed into fat.

Osaterone acetate Chemical compound

Osaterone acetate, sold under the brand name Ypozane, is a medication which is used in veterinary medicine in Europe in the treatment of enlarged prostate in dogs. It is given by mouth.

<span class="mw-page-title-main">Progestogen ester</span>

A progestogen ester is an ester of a progestogen or progestin. The prototypical progestogen is progesterone, an endogenous sex hormone. Esterification is frequently employed to improve the pharmacokinetics of steroids, including oral bioavailability, lipophilicity, and elimination half-life. In addition, with intramuscular injection, steroid esters are often absorbed more slowly into the body, allowing for less frequent administration. Many steroid esters function as prodrugs.

Bromoketoprogesterone

Bromoketoprogesterone (BKP), also known as 9α-bromo-11-oxoprogesterone (BOP), and known by the tentative brand name Braxarone (Squibb), is an orally active progestin which does not appear to have been marketed.

<span class="mw-page-title-main">Pharmacology of cyproterone acetate</span>

The pharmacology of cyproterone acetate (CPA) concerns the pharmacology of the steroidal antiandrogen and progestin medication cyproterone acetate.

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