Estradiol valerate (EV), sold for use by mouth under the brand name Progynova and Primiwal E4 and for use by injection under the brand names Delestrogen and Progynon Depot among others, is an estrogen medication. It is used in hormone therapy for menopausal symptoms and low estrogen levels, hormone therapy for transgender people, and in hormonal birth control. It is also used in the treatment of prostate cancer. The medication is taken by mouth or by injection into muscle or fat once every 1 to 4 weeks.
Combined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy.
Estradiol benzoate (EB), sold under the brand name Progynon-B among others, is an estrogen medication which is used in hormone therapy for menopausal symptoms and low estrogen levels in women, in hormone therapy for transgender women, and in the treatment of gynecological disorders. It is also used in the treatment of prostate cancer in men. Estradiol benzoate is used in veterinary medicine as well. When used clinically, the medication is given by injection into muscle usually two to three times per week.
Estradiol cypionate (EC), sold under the brand name Depo-Estradiol among others, is an estrogen medication which is used in hormone therapy for menopausal symptoms and low estrogen levels in cis women, in hormone therapy for trans women, and in hormonal birth control for cis women. It is given by injection into muscle once every 1 to 4 weeks.
Estradiol undecylate, also known as estradiol undecanoate and formerly sold under the brand names Delestrec and Progynon Depot 100 among others, is an estrogen medication which has been used in the treatment of prostate cancer in men. It has also been used as a part of hormone therapy for transgender women. Although estradiol undecylate has been used in the past, it was discontinued and hence is no longer available. The medication has been given by injection into muscle usually once a month.
Estradiol dipropionate (EDP), sold under the brand names Agofollin, Di-Ovocylin, and Progynon DP among others, is an estrogen medication which has been used in hormone therapy for menopausal symptoms and low estrogen levels in women and in the treatment of gynecological disorders. It has also been used in feminizing hormone therapy for transgender women and in the treatment of prostate cancer in men. Although widely used in the past, estradiol dipropionate has largely been discontinued and is mostly no longer available today. It appears to remain in use only in Japan, Macedonia, and Australia. Estradiol dipropionate is given by injection into muscle at intervals ranging from once or twice a week to once every week and a half to two weeks.
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 with increased resistance to first-pass metabolism, slightly improving its oral bioavailability. In addition, estrogen esters have increased lipophilicity, which results in a longer duration when given by intramuscular or subcutaneous injection due to the formation of a long-lasting local depot in muscle and fat. Conversely, this is not the case with intravenous injection or oral administration. Estrogen esters are rapidly hydrolyzed into their parent estrogen by esterases once they have been released from the depot. Because estradiol esters are prodrugs of estradiol, they are considered to be natural and bioidentical forms of estrogen.
Estradiol hexahydrobenzoate (EHHB), sold under a number of brand names including Benzo-Ginoestril A.P., BenzoGynoestryl Retard, Ginestryl-15-Depot, Menodin, and Tardoginestryl, is an estrogen medication which was previously used for indications such as menopausal hormone therapy and gynecological disorders. EHHB is given by injection into muscle at regular intervals, for instance once every few weeks.
Estradiol stearate (E2-17-St), also known as estradiol octadecanoate and sold under the brand name Depofollan, is a naturally occurring estrogen and an estrogen ester – specifically, the C17β stearate ester of estradiol. It occurs in the body as a very long-lasting metabolite and prohormone of estradiol. The compound is one of the components that collectively constitute lipoidal estradiol, another of which is estradiol palmitate. It is extremely lipophilic and hydrophobic. Estradiol stearate has no affinity for the estrogen receptor, requiring transformation into estradiol via esterases for its estrogenic activity. The compound does not bind to sex hormone-binding globulin or α-fetoprotein, instead being transported by lipoproteins such as high-density lipoprotein and low-density lipoprotein.
Estradiol dienanthate (EDE), sold under the brand names Climacteron among others, is a long-acting estrogen medication which was previously used in menopausal hormone therapy for women and to suppress lactation in women. It was formulated in combination with estradiol benzoate (EB), a short-acting estrogen, and testosterone enanthate benzilic acid hydrazone (TEBH), a long-acting androgen/anabolic steroid. EDE has not been made available for medical use alone. The medication, in combination with EB and TEBH, was given by injection into muscle once or at regular intervals, for instance once every 6 weeks.
Estradiol benzoate butyrate (EBB), sold under the brand names Neolutin N, Redimen, Soluna, and Unijab and formerly known under the developmental code name Unimens, is an estrogen medication which is used in hormonal birth control for women. It is formulated in combination with dihydroxyprogesterone acetophenide, a progestin, and is used specifically as a combined injectable contraceptive. EBB is not available for medical use alone. The medication, in combination with DHPA, is given by injection into muscle once a month.
Testosterone enantate benzilic acid hydrazone (TEBH), or testosterone 17β-enantate 3-benzilic acid hydrazone, is a synthetic, injected androgen/anabolic steroid and an androgen ester – specifically, the C17β enantate (heptanoate) ester and C3 benzilic acid hydrazone of testosterone. It was previously marketed in combination with estradiol benzoate and estradiol dienantate under the brand names Climacteron, Lactimex, and Lactostat. Clinical studies have assessed this formulation. TEBH was first described in the scientific literature in 1959. It is a very long-lasting prodrug of testosterone when administered in oil via intramuscular injection.
Estradiol sulfamate, or estradiol-3-O-sulfamate, is a steroid sulfatase (STS) inhibitor which is under development for the treatment of endometriosis. It is the C3 sulfamate ester of estradiol, and was originally thought to be a prodrug of estradiol. The drug was first synthesized as an STS inhibitor along with its oxidized version estrone 3-O-sulfamate (EMATE) in the group of Professor Barry V L Potter at the University of Bath, UK, working together with Professor Michael J Reed at Imperial College, London and was found to be highly estrogenic in rodents. Such aryl sulfamate esters were shown to be "first-in-class" highly potent active site-directed irreversible STS inhibitors. Compounds of this class are thought to irreversibly modify the active site formylglycine residue of STS. The drug shows profoundly reduced susceptibility to first-pass metabolism relative to estradiol, and was believed to be the first "potent" estradiol prodrug to be discovered. It was clinically investigated for possible use as an estrogen for indications like hormonal contraception and menopausal hormone therapy. However, it showed no estrogenic effects in women. The potent non-estrogenic clinical STS inhibitor Irosustat (STX64/667-Coumate) was used to explore the possibility that STS might be responsible for the hydrolysis of estrogen sulphamates. Results demonstrated convincingly that STS is the enzyme responsible for the removal of the sulfamoyl group from estrogen sulfamates and has a crucial role in regulating the estrogenicity associated with this class of drug. Thus, STS inhibition blocks the conversion of E2MATE into estradiol and thereby abolishes its estrogenicity in humans. Irosustat has completed a number of clinical trials in oncology as an STS inhibitor currently up to Phase II.
Estrone sulfamate, or estrone-3-O-sulfamate, is a steroid sulfatase (STS) inhibitor which has not yet been marketed. It is the C3 sulfamate ester of the estrogen estrone. Unlike other estrogen esters however, EMATE is not an effective prodrug of estrogens. A closely related compound is estradiol sulfamate (E2MATE), which is extensively metabolized into EMATE and has similar properties to it.
Estrone (E1), sold under the brand names Estragyn, Kestrin, and Theelin among many others, is an estrogen medication and naturally occurring steroid hormone which has been used in menopausal hormone therapy and for other indications. It has been provided as an aqueous suspension or oil solution given by injection into muscle and as a vaginal cream applied inside of the vagina. It can also be taken by mouth as estradiol/estrone/estriol and in the form of prodrugs like estropipate and conjugated estrogens.
EC508, also known as estradiol 17β-(1- -L-proline), is an estrogen which is under development by Evestra for use in menopausal hormone therapy and as a hormonal contraceptive for the prevention of pregnancy in women. It is an orally active estrogen ester – specifically, a C17β sulfonamide–proline ester of the natural and bioidentical estrogen estradiol – and acts as a prodrug of estradiol in the body. However, unlike oral estradiol and conventional oral estradiol esters such as estradiol valerate, EC508 undergoes little or no first-pass metabolism, has high oral bioavailability, and does not have disproportionate estrogenic effects in the liver. As such, it has a variety of desirable advantages over oral estradiol, similarly to parenteral estradiol, but with the convenience of oral administration. EC508 is a candidate with the potential to replace not only oral estradiol in clinical practice, but also ethinylestradiol in oral contraceptives. Evestra intends to seek Investigational New Drug status for EC508 in the second quarter of 2018.
Ethinylestradiol sulfamate, or 17α-ethynylestradiol 3-O-sulfamate, is a synthetic estrogen and estrogen ester which was never marketed. It is the C3 sulfamate ester of ethinylestradiol. The drug shows considerably improved oral estrogenic potency (uterotrophic) relative to ethinylestradiol in rats but without an increase in hepatic estrogenic potency. Related compounds like ethinylestradiol N,N-diethylsulfamate (J271) and ethinylestradiol pyrrolidinosulfonate (J272) have also been developed, and have similar properties in animals. However, the closely related compound estradiol sulfamate (E2MATE) failed to show estrogenic activity in humans, which is due to the fact that it is additionally a highly potent inhibitor of steroid sulfatase and prevents its own bioactivation into estradiol.
The pharmacology of estradiol, an estrogen medication and naturally occurring steroid hormone, concerns its pharmacodynamics, pharmacokinetics, and various routes of administration.
Estradiol benzoate/progesterone (EB/P4), sold under the brand names Duogynon and Sistocyclin among others, is a combination medication of estradiol benzoate (EB), an estrogen, and progesterone (P4), a progestogen. It has been formulated both as short-acting oil solutions and long-acting microcrystalline aqueous suspensions and is given by injection into muscle either once or continuously at regular intervals.
