Hydroxyprogesterone caproate

Hydroxyprogesterone caproate, sold under the brand name Delalutin among others, is a medication used to reduce the risk of preterm birth in women pregnant with one baby who have a history of spontaneous preterm birth. In March 2023, the manufacturer, Covis Pharma, agreed to withdraw the drug from the US market. The approval of this drug substance was withdrawn by the US Food and Drug Administration (FDA) in April 2023. In May 2024, the Pharmacovigilance Risk Assessment Committee of the European Medicines Agency recommended suspending the marketing authorizations of medications containing 17-hydroxyprogesterone caproate in the European Union.

Hydroxyprogesterone caproate is a progestin medication which was used to prevent preterm birth in pregnant women with a history of the condition and to treat gynecological disorders. It has also been formulated in combination with estrogens for various indications (brand names Gravibinon and Primosiston) and as a form of long-lasting injectable birth control (brand name Chinese Injectable No. 1). It is not used by mouth and is instead given by injection into muscle or fat.

Hydroxyprogesterone caproate is generally well tolerated and produces few side effects. Injection site reactions such as pain and swelling are the most common side effect of hydroxyprogesterone caproate. The medication may increase the risk of gestational diabetes when used in pregnant women. Hydroxyprogesterone caproate is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. It has some antimineralocorticoid activity and no other important hormonal activity. The medication shows a number of differences from natural progesterone.

Hydroxyprogesterone caproate was discovered in 1953 and was introduced for medical use in 1954 or 1955. It was marketed in the United States under the brand name Delalutin and throughout Europe under the brand name Proluton. The medication was discontinued in the United States in 1999. However, hydroxyprogesterone caproate was subsequently reintroduced in the United States under the brand name Makena for the treatment of preterm birth in 2011 until the FDA banned 17α-OHPC in 2023.