Altrenogest, sold under the brand names Swinemate and Altren manufactured by Aurora Pharmaceutical and Regumate manufactured by Merck, is a

progestin 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. ...

of the

19-nortestosterone Nandrolone, also known as 19-nortestosterone, is an endogenous androgen. It is also an anabolic steroid (AAS) which is medically used in the form of esters such as nandrolone decanoate (brand name Deca-Durabolin) and nandrolone phenylpropionat ...

group which is widely used in

veterinary medicine Veterinary medicine is the branch of medicine that deals with the prevention, management, medical diagnosis, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all a ...

to suppress or synchronize

estrus The estrous cycle (, originally ) is a set of recurring physiological changes induced by reproductive hormones in females of mammalian subclass Theria. Estrous cycles start after sexual maturity in females and are interrupted by anestrous phas ...

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 mi ...

s and

pig The pig (''Sus domesticus''), also called swine (: swine) or hog, is an omnivorous, domesticated, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of the genus '' Sus''. Some authorities cons ...

s. It is available for veterinary use in both

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

(as Regumate) and the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

(as Matrix).

Uses

Veterinary

Altrenogest is used in

Pharmacology

Pharmacodynamics

An ''

in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom (biology), kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are est ...

structure–activity relationship The structure–activity relationship (SAR) is the relationship between the chemical structure of a molecule and its biological activity. This idea was first presented by Alexander Crum Brown and Thomas Richard Fraser at least as early as 1868. Th ...

bioassay A bioassay is an analytical method to determine the potency or effect of a substance by its effect on animal testing, living animals or plants (''in vivo''), or on living cells or tissues (''in vitro''). A bioassay can be either quantal or quantit ...

study found that altrenogest was the most potent

agonist An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an R ...

of both the

progesterone receptor The progesterone receptor (PR), also known as NR3C3 or nuclear receptor subfamily 3, group C, member 3, is a protein found inside cells. It is activated by the steroid hormone progesterone. In humans, PR is encoded by a single ''PGR'' gene resi ...

(PR) and the

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in th ...

(AR) of a large selection of other

progestogen Progestogens, also sometimes written progestins, 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 progestoge ...

s as well as

anabolic–androgenic steroid Anabolic steroids, also known as anabolic-androgenic steroids (AAS), are a class of drugs that are structurally related to testosterone, the main male sex hormone, and produce effects by binding to the androgen receptor (AR). Anabolism, Anaboli ...

s (AAS). The observed potency of altrenogest even exceeded that of metribolone (methyltrienolone, R-1881), which was the second most potent compound. In the study, it showed an EC₅₀ of 0.64 nM for the AR and 688% of the relative activational potency of

testosterone Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

and an EC₅₀ of 0.3 nM and 1,300% of the relative activational potency of

progesterone Progesterone (; P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the ma ...

, with an AR/PR activational potency ratio of 0.53. Although very potent in both activities ''in vitro'', the AR/PR activational potency ratio of altrenogest was in the same range as that of other 19-nortestosterone progestins such as

norethisterone Norethisterone, also known as norethindrone and sold under the brand name Norlutin among others, is a progestin medication used in birth control pills, menopausal hormone therapy, and for the treatment of gynecological disorders. The medicatio ...

noretynodrel Noretynodrel, or norethynodrel, sold under the brand name Enovid among others, is a progestin medication which was previously used in birth control pills and in the treatment of gynecological disorders but is now no longer marketed. It was availa ...

norgestrel Norgestrel, sold under the brand name Opill among others, is a progestin which is used in birth control pills. It is often combined with the estrogen ethinylestradiol, marketed as Ovral. It is also used in menopausal hormone therapy. It is t ...

, and allylestrenol (ratio for all < 1.0), whereas the AR/PR activational potency ratio of its 17α-deallylated AAS analogue trenbolone was, at 64, profoundly increased (although the ratio of metribolone (the 17α-methylated variant of altrenogest), at 0.56, was almost the same as that of altrenogest). According to its

manufacturer Manufacturing is the creation or Production (economics), production of goods with the help of equipment, Work (human activity), labor, machines, tools, and chemical or biological processing or formulation. It is the essence of the secondary se ...

Roussel Uclaf Roussel Uclaf S.A. was a French pharmaceutical company and one of several predecessor companies of today's Sanofi. It was the second largest French pharmaceutical company before it was acquired by Hoechst AG of Frankfurt, Germany in 1997, with p ...

, altrenogest has weak

anabolic Anabolism () is the set of metabolic pathways that construct macromolecules like DNA or RNA from smaller units. These reactions require energy, known also as an endergonic process. Anabolism is the building-up aspect of metabolism, whereas catab ...

and

androgen An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

ic activity equivalent to 1/20th of that of

. However, no significant androgenic effects have been observed in young

stallion A stallion is an adult male horse that has not been gelded ( castrated). Stallions follow the conformation and phenotype of their breed, but within that standard, the presence of hormones such as testosterone may give stallions a thicker, "cre ...

s or mature

mare A mare is an adult female horse or other equidae, equine. In most cases, a mare is a female horse over the age of three, and a filly is a female horse three and younger. In Thoroughbred horse racing, a mare is defined as a female horse more th ...

s, and altrenogest has notably been used to maintain

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

in mares (similarly to the use of allylestrenol to maintain pregnancy in women) with no incidence of

virilization Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is a medical term commonly used in three medical a ...

or other abnormalities in

filly A filly is a female horse that is too young to be called a mare. There are two specific definitions in use: *In most cases, a ''filly'' is a female horse under four years old. *In some nations, such as the United Kingdom and the United States ...

offspring In biology, offspring are the young creation of living organisms, produced either by sexual reproduction, sexual or asexual reproduction. Collective offspring may be known as a brood or progeny. This can refer to a set of simultaneous offspring ...

. On the other hand, minor potential anabolic/androgenic effects have been suggested for altrenogest in pigs.

Chemistry

Altrenogest, also known as 17α-allyl-19-nor-δ^9,11-testosterone or as 17α-allylestra-4,9,11-trien-17β-ol-3-one, is a

synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

estrane Estrane is a C18 steroid derivative, with a gonane core. ''Estrenes'' are estrane derivatives that contain a double bond, with an example being nandrolone. ''Estratrienes'' (estrins) are estrane derivatives that contain three double bonds, for i ...

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

and

derivative In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is t ...

and 17α-allyltestosterone, or of 17α-allyl-19-nortestosterone. It is one of only two marketed progestins that possesses a 17α-allyl group, the other being allylestrenol. Most other progestins possess a 17α- ethynyl group, while AAS, if they are 17α-substituted, are usually 17α-alkylated (with a

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as ...

ethyl group In organic chemistry, an ethyl group (abbr. Et) is an alkyl substituent with the formula , derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry The International Union of Pure and Applied ...

). Altrenogest is the 17α-allylated derivative of the AAS

trenbolone Trenbolone is an androgen and anabolic steroid (AAS) of the nandrolone group which itself was never marketed. Trenbolone ester prodrugs, including trenbolone acetate (brand names Finajet, Finaplix, others) and trenbolone hexahydrobenzylcarbonat ...

(and hence can also be referred to as allyltrenbolone or allyltrienolone), which itself is the 9,11-didehydro analogue of the AAS

nandrolone Nandrolone, also known as 19-nortestosterone, is an endogenous androgen. It is also an anabolic steroid (AAS) which is medically used in the form of esters such as nandrolone decanoate (brand name Deca-Durabolin) and nandrolone phenylpropionate ...

(19-nortestosterone). Altrenogest is also closely related to norgestrienone.

History

Altrenogest has been marketed as Regumate since the early 1980s.

Society and culture

Generic names

''Altrenogest'' is the generic name of the drug and its , , and , while ''altrénogest'' is its .

Brand names

Altrenogest is marketed under the brand names Regumate and Matrix among others.

References

{{Progesterone receptor modulators Tertiary alcohols Allyl compounds Estranes Enones Progestogens Veterinary drugs Polyenes