FDA OK's drug to reduce preterm birth risk

The U.S. Food and Drug Administration (FDA) has approved a drug to reduce the risk of preterm birth in at-risk pregnant woman.

The Makena injection, which is manufactured by Baxter Pharmaceutical Solutions LLC, got the green signal from the FDA to reduce the risk of preterm delivery before 37 weeks of pregnancy, in pregnant women with a history of at least one spontaneous preterm birth.

The U.S. health regulator cleared Makena under the agency's accelerated approval regulations that allow promising drugs to be approved based on a surrogate endpoint benefit (here, reducing the risk of delivery before 37 weeks of pregnancy) that is reasonably likely to predict a clinical benefit.

Preterm birth is a significant public health issue in the United States, said Sandra Kweder of the FDA. This is the first drug approved by the FDA that is indicated to specifically reduce this risk.

The agency said a health care provider would give Makena once a week by injection into the hip. Treatment should begin at 16 weeks and no later than 21 weeks of pregnancy.

The FDA reviewed data on the safety and effectiveness of Makena in a multicenter randomized double-blind clinical trial. The study included 463 women 16 to 43 years of age who were pregnant with a single fetus and had a history of a prior spontaneous preterm birth. Among women treated with Makena, 37 percent delivered early (before 37 weeks) as compared with 55 percent of women in the control group.

A separate study evaluated the development of children born to mothers enrolled in the controlled trial. In this study, children ages 2.5 years to 5 years reached similar developmental targets, regardless of the mother's treatment. The confirmatory study that is ongoing will be followed by a similar infant follow-up study, to be completed about 2018. That study is expected to include 580-750 infants.

According to the FDA, the most common side effects reported with Makena included pain, swelling, or itching at the injection site; hives, nausea and diarrhea. Serious adverse reactions were rare.

The agency originally approved hydroxyprogesterone caproate under the trade name Delalutin in 1956 for use in pregnant women. The approved indications include threatened miscarriage. The original manufacturer requested the withdrawal of Delalutin from the market in 2000 for reasons unrelated to safety.