|Other names||LPP; 17α-Ethynylestr-4-en-17β-ol 17β-(3-phenylpropionate); 19-Nor-17α-pregn-4-en-20-yn-17-ol benzenepropanoate|
|Drug class||Progestogen; Progestin; Progestogen ester|
|Chemical and physical data|
|Molar mass||416.602 g/mol g·mol−1|
|3D model (JSmol)|
Lynestrenol phenylpropionate (LPP), also known as ethynylestrenol phenylpropionate, is a progestin and a progestogen ester which was developed for potential use as a progestogen-only injectable contraceptive by Organon but was never marketed. It was assessed at doses of 25 to 75 mg in an oil solution once a month by intramuscular injection. LPP was associated with high contraceptive failure at the low dose and with poor cycle control. The medication was found to produce estrogenic effects in the endometrium in women due to transformation into estrogenic metabolites.
A single intramuscular injection of 50 to 100 mg LPP in oil solution has been found to have a duration of action of 14 to 30 days in terms of clinical biological effect in the uterus and on body temperature in women.
LPP has a long biological half-life in rats when given as an intramuscular depot injection; its half-life was similar to that of nandrolone laurate (nandrolone dodecanoate) and was about 2-fold longer than that of nandrolone decanoate, 10-fold longer than that of lynestrenol and nandrolone phenylpropionate, 50-fold longer than that of progesterone, and 430-fold longer than that of nandrolone.
|Progestogen||Form||Major brand names||Class||TFD
|Algestone acetophenide||Oil solution||Perlutal, Topasel, Yectames||Pregnane||?||–||75–150 mg||100 mg ≈ 14–32 days|
|Cyproterone acetate||Oil solution||Androcur Depot||Pregnane||?||–||–||300 mg ≈ 20 days|
|Dydrogesteronea||Aqueous suspension||–||Retropregnane||?||–||–||100 mg ≈ 16–38 days|
|Gestonorone caproate||Oil solution||Depostat, Primostat||Norpregnane||50 mg||–||–||25–50 mg ≈ 8–13 days|
|Hydroxyprogesterone acetatea||Aqueous suspension||–||Pregnane||350 mg||–||–||150–350 mg ≈ 9–16 days|
|Hydroxyprogesterone caproate||Oil solution||Delalutin, Proluton, Makena||Pregnane||250–500 mgb||–||250–500 mg||65–500 mg ≈ 5–21 days|
|Levonorgestrel butanoatea||Aqueous suspension||–||Gonane||?||–||–||5–50 mg ≈ 3–6 months|
|Lynestrenol phenylpropionatea||Oil solution||–||Estrane||?||–||–||50–100 mg ≈ 14–30 days|
|Medroxyprogesterone acetate||Aqueous suspension||Depo-Provera||Pregnane||50–100 mg||150 mg||25 mg||50–150 mg ≈ 14–50+ days|
|Megestrol acetate||Aqueous suspension||Mego-E||Pregnane||?||–||25 mg||25 mg ≈ >14 daysc|
|Norethisterone enanthate||Oil solution||Noristerat, Mesigyna||Estrane||100–200 mg||200 mg||50 mg||50–200 mg ≈ 11–52 days|
|Oxogestone phenylpropionatea||Oil solution||–||Norpregnane||?||–||–||100 mg ≈ 19–20 days|
|Progesterone||Oil solution||Progestaject, Gestone, Strone||Pregnane||200 mgb||–||–||25–350 mg ≈ 2–6 days|
|Aqueous suspension||Agolutin Depot||Pregnane||50–200 mg||–||–||50–300 mg ≈ 7–14 days|
|Note: All by intramuscular or subcutaneous injection. All are synthetic except for P4, which is bioidentical. P4 production during the luteal phase is ~25 (15–50) mg/day. The OID of OHPC is 250 to 500 mg/month. Footnotes: a = Never marketed by this route. b = In divided doses (2 × 125 or 250 mg for OHPC, 10 × 20 mg for P4). c = Half-life is ~14 days. Sources: Main: See template.|
Studies were made with nandrolone phenpropionate (Durabolin), nandrolone decanoate, and 16α-ethylprogesterone in peanut oil injected into the gastrocnemius muscle of rats. The free steroid was much more rapidly resorbed than the esters, explaining the action-prolonging effects obtained with the latter. Generally, resorption rates correlated well with duration of action. Resorption from the muscle was followed by transport to the receptor site in the body, during which time ester hydrolysis may occur, releasing the free steroid. Resorption and hydrolysis take place independently, since plasma with inactivated enzymes (heated to 55°) eluted the compds. from a filter paper strip as rapidly as did normal plasma.