|Synonyms||LNG-B; HRP-002; Levonorgestrel 17β-butanoate; 17α-Ethynyl-18-methyl-19-nortestosterone 17β-butanoate; 17α-Ethynyl-18-methylestr-4-en-17β-ol-3-one 17β-butanoate|
|Drug class||Progestogen; Progestogen ester|
|Chemical and physical data|
|Molar mass||382.544 g/mol g·mol−1|
|3D model (JSmol)|
Levonorgestrel butanoate (LNG-B) (developmental code name HRP-002), or levonorgestrel 17β-butanoate, is a steroidal progestin of the 19-nortestosterone group which was developed by the World Health Organization (WHO) in collaboration with the Contraceptive Development Branch (CDB) of the National Institute of Child Health and Human Development as a long-acting injectable contraceptive. It is the C17β butanoate ester of levonorgestrel, and acts as a prodrug of levonorgestrel in the body. The drug is at or beyond the phase III stage of clinical development, but has not been marketed at this time. It was first described in the literature, by the WHO, in 1983, and has been under investigation for potential clinical use since then.
LNG-B has been under investigation as a long-lasting injectable contraceptive for women. A single intramuscular injection of an aqueous suspension of 5 or 10 mg LNG-B has a duration of 3 months, whereas an injection of 50 mg has a duration of 6 months. The drug was also previously tested successfully as a combined injectable contraceptive with estradiol hexahydrobenzoate, but this formulation was never marketed. LNG-B has been tested successfully in combination with testosterone buciclate as a long-lasting injectable contraceptive for men as well.
LNG-B may have several advantages over depot medroxyprogesterone acetate, including the use of much lower comparative dosages, reduced progestogenic side effects like hypogonadism and amenorrhea, and a more rapid return in fertility following discontinuation. The drug has a well-established safety record owing to the use of levonorgestrel as an oral contraceptive since the 1960s.
|Algestone acetophenide||Synthetic||Pregnane||?||–||75–150 mg||100 mg ≈ 14–32 days|
|Cyproterone acetate||Synthetic||Pregnane||?||–||–||300 mg ≈ 20 days|
|Dydrogesterone (aq. susp.)a||Synthetic||Retropregnane||?||–||–||100 mg ≈ 16–38 days|
|Gestonorone caproate||Synthetic||Norpregnane||50 mg||–||–||25–50 mg ≈ 8–13 days|
|Hydroxyprogesterone acetate (aq. susp.)a||Synthetic||Pregnane||350 mg||–||–||150–350 mg ≈ 9–16 days|
|Hydroxyprogesterone caproate||Synthetic||Pregnane||250–500 mgb||–||250–500 mg||65–500 mg ≈ 5–21 days|
|Levonorgestrel butanoate (aq. susp.)a||Synthetic||Estrane||?||–||–||5–50 mg ≈ 3–6 months|
|Lynestrenol phenylpropionatea||Synthetic||Estrane||?||–||–||50–100 mg ≈ 14–30 days|
|Medroxyprogesterone acetate (aq. susp.)||Synthetic||Pregnane||50–100 mg||150 mg||25 mg||50–150 mg ≈ 14–50+ days|
|Megestrol acetate (aq. susp.)||Synthetic||Pregnane||?||–||25 mg||25 mg ≈ >14 daysc|
|Norethisterone enanthate||Synthetic||Estrane||100–200 mg||200 mg||50 mg||50–200 mg ≈ 11–52 days|
|Oxogestone phenylpropionatea||Synthetic||Pregnane||?||–||–||100 mg ≈ 19–20 days|
|Progesterone||Bioidentical||Pregnane||200 mgb||–||–||25–350 mg ≈ 2–6 days|
|Progesterone (aq. susp.)||Bioidentical||Pregnane||50–200 mg||–||–||50–300 mg ≈ 7–14 days|
|Note: All are via i.m. or s.c. injection of oil solution unless noted otherwise. P4 production during the luteal phase is ~25 (15–50) mg/day. The OID of OHPC is 250 to 500 mg/month. Footnotes: a = Studied but never marketed (either as a medication or 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.|
- List of progestogen esters § Esters of 19-nortestosterone derivatives
- Progestogen-only injectable contraceptive
- Special Programme on Human Reproduction
- King TL, Brucker MC, Kriebs JM, Fahey JO (21 October 2013). Varney's Midwifery. Jones & Bartlett Publishers. pp. 495–. ISBN 978-1-284-02542-2.
- Shalender Bhasin (13 February 1996). Pharmacology, Biology, and Clinical Applications of Androgens: Current Status and Future Prospects. John Wiley & Sons. pp. 401–. ISBN 978-0-471-13320-9.
- Benno Clemens Runnebaum; Thomas Rabe; Ludwig Kiesel (6 December 2012). Female Contraception: Update and Trends. Springer Science & Business Media. pp. 429–. ISBN 978-3-642-73790-9.
- Crabbé P, Archer S, Benagiano G, Diczfalusy E, Djerassi C, Fried J, Higuchi T (1983). "Long-acting contraceptive agents: design of the WHO Chemical Synthesis Programme". Steroids. 41 (3): 243–53. doi:10.1016/0039-128X(83)90095-8. PMID 6658872.
- Koetsawang S (1991). "The injectable contraceptive: present and future trends". Ann. N. Y. Acad. Sci. 626: 30–42. doi:10.1111/j.1749-6632.1991.tb37897.x. PMID 1829341.
- Benagiano, G., & Merialdi, M. (2011). Carl Djerassi and the World Health Organisation special programme of research in human reproduction. Journal für Reproduktionsmedizin und Endokrinologie-Journal of Reproductive Medicine and Endocrinology, 8(1), 10-13. http://www.kup.at/kup/pdf/10163.pdf
- Paolo Giovanni Artini; Andrea R. Genazzani; Felice Petraglia (11 December 2001). Advances in Gynecological Endocrinology. CRC Press. pp. 105–. ISBN 978-1-84214-071-0.
- C. Coutifaris; L. Mastroianni (15 August 1997). New Horizons in Reproductive Medicine. CRC Press. pp. 101–. ISBN 978-1-85070-793-6.
- Shio Kumar Singh (4 September 2015). Mammalian Endocrinology and Male Reproductive Biology. CRC Press. pp. 270–. ISBN 978-1-4987-2736-5.
- Pramilla Senanayake; Malcolm Potts (14 April 2008). Atlas of Contraception, Second Edition. CRC Press. pp. 49–. ISBN 978-0-203-34732-4.