Quinestrol, also known as ethinylestradiol cyclopentyl ether (EECPE), sold under the brand name Estrovis among others, is an

estrogen Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three ...

medication which has been used in

menopausal hormone therapy Hormone replacement therapy (HRT), also known as menopausal hormone therapy or postmenopausal hormone therapy, is a form of hormone therapy used to treat symptoms associated with female menopause. Effects of menopause can include symptoms such ...

hormonal birth control Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The origin ...

, and to treat

breast cancer Breast cancer is a cancer that develops from breast tissue. Signs of breast cancer may include a Breast lump, lump in the breast, a change in breast shape, dimpling of the skin, Milk-rejection sign, milk rejection, fluid coming from the nipp ...

and

prostate cancer Prostate cancer is the neoplasm, uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of the prostate tissue is usually detected through Screening (medicine), screening tests, ...

. It is taken once per week to once per month

by mouth Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications. Oral administ ...

Medical uses

Quinestrol has been used as the estrogen component in

and in

combined hormonal birth control Combined hormonal contraception (CHC), or combined birth control, is a form of hormonal contraception which combines both an estrogen and a progestogen in varying formulations. The different types available include the pill, the patch and the v ...

. It has also occasionally been used in the treatment of

and

, as well as to suppress

lactation Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The process ...

. On its own as an estrogen, quinestrol was taken once per week

. As a

combined birth control pill The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. It is the oral form of combined hormonal contra ...

, it was used together with

quingestanol acetate Quingestanol acetate, sold under the brand names Demovis and Pilomin among others, is a progestin medication which was used in birth control pills but is no longer marketed. It is taken by mouth. Quingestanol acetate is a progestin, or a synthe ...

and was taken once per month by mouth.

Pharmacology

Quinestrol is a

prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ...

ethinylestradiol Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. Ethinylestradiol was widely used for various indications such as the treatment of menopausal symptoms, gynecological ...

(EE), with no estrogenic activity of its own. It is taken orally and has prolonged activity following a single dose, with a very long

biological half-life Biological half-life (elimination half-life, pharmacological half-life) is the time taken for concentration of a drug, biological substance (such as a medication) to decrease from its maximum concentration (chemistry), concentration (Cmax (pharm ...

of more than 120 hours (5 days) due to enhanced

lipophilicity Lipophilicity (from Greek λίπος "fat" and φίλος "friendly") is the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such compounds are called lipophilic (translated ...

and storage in

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers specif ...

. Because of its much longer half-life, quinestrol is two to three times as potent as EE. Also because of its long half-life, quinestrol can be taken once a week or once a month. Following administration, quinestrol is absorbed via the

lymphatic system The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphoid organs, lympha ...

, is stored in

adipose tissue Adipose tissue (also known as body fat or simply fat) is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, Blood vessel, vascular endothel ...

, and is gradually released from adipose tissue.

Chemistry

Quinestrol, also known as ethinylestradiol 3-cyclopentyl ether (EE2CPE), 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 a

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 ...

estradiol Estradiol (E2), also called oestrogen, oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of female reproductive cycles such as estrous and menstrual cycles. Estradiol is responsible ...

. It is an

estrogen ether An estrogen ester is an ester of an estrogen, most typically of estradiol but also of other estrogens such as estrone, estriol, and even nonsteroidal estrogens like diethylstilbestrol. Esterification renders estradiol into a prodrug of estradiol ...

, specifically the C3 cyclopentyl

ether In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R� ...

(17α-ethynylestradiol). Closely related estrogens include

mestranol Mestranol, sold under the brand names Enovid, Norinyl, and Ortho-Novum among others, is an estrogen medication which has been used in birth control pills, menopausal hormone therapy, and the treatment of menstrual disorders. It is formulated in ...

(ethinylestradiol 3-methyl ether) and

ethinylestradiol sulfonate Ethinylestradiol sulfonate (EES), sold under the brand names Deposiston and Turisteron among others, is an estrogen medication which has been used in birth control pills for women and in the treatment of prostate cancer in men. It has also been ...

(EES; Turisteron; ethinylestradiol 3-isopropylsulfonate).

History

Quinestrol was developed and introduced for medical use in the 1960s.

Society and culture

Generic names

''Quinestrol'' is the generic name of the drug and its , , and . It is also known by its former developmental code name ''W-3566''.

Brand names

Quinestrol has been marketed under brand names including Agalacto-Quilea, Basaquines, Eston, Estrovis, Estrovister, Plestrovis, Qui-Lea, Soluna, and Yueketing, among others.

Availability

Quinestrol was marketed as ''Estrovis'' in 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 ...

Parke-Davis Parke-Davis is a subsidiary of the pharmaceutical company Pfizer. Although Parke, Davis & Co. is no longer an independent corporation, it was once America's oldest and largest drug maker, and played an important role in medical history. In 1970 ...

and as ''Qui-Lea'' in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

, but is reportedly not currently marketed. However, it does appear to still be available as an

oral contraceptive Oral contraceptives, abbreviated OCPs, also known as birth control pills, are medications taken by mouth for the purpose of birth control. The introduction of the birth control pill ("the Pill") in 1960 revolutionized the options for contraception, ...

in combination with

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. ...

s in Argentina and

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. One tablet form available in China consists of 6 mg levonorgestrel and 3 mg quinestrol; it is used as a prescription "long-term" oral contraceptive, with one dose taken each month. It is sold under various brand names including Yuèkětíng () and Àiyuè (). A version with the racemic

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 ...

in place of levonorgestrel also appears to be available.

Veterinary use

Rodents

The Chinese levonorgestrel/quinestrol 2:1 formula is known as EP-1 in veterinary practice. It is known to have some organ-specific effects on the

Mongolian gerbil The Mongolian gerbil or Mongolian jird (''Meriones unguiculatus'') is a rodent belonging to the subfamily Gerbillinae. Their body size is typically , with a tail, and body weight , with adult males larger than females. The animal is used in ...

as measured by receptor mRNA expression. Incorporated into baits at a concentration of 50 ppm, EP-1 has been used to control wild Mongolian gerbil populations with some success.

References

{{Estrogen receptor modulators Ethynyl compounds Antigonadotropins Cyclopentyl ethers Estranes Estrogen ethers Synthetic estrogens Tertiary alcohols