Drug aims to reduce risk of premature labor
Pregnant women at risk of going into premature labor now finally have a drug option that researchers say can help them reach full term. The US Food and Drug Administration yesterday approved Makena, a progesterone injection to reduce the risk of preterm delivery in women who have already had a preterm birth — defined as before 37 weeks of pregnancy.
About 12 percent of women give birth prematurely, and preterm babies are at greater risk of having lung problems, learning disabilities, and of dying during infancy and even later in childhood, according to a 2008 study published in the Journal of the American Medical Association.
“It’s really exciting to have this approved. We’ve been waiting for this for a while,’’ said Dr. Errol R. Norwitz, chairman of obstetrics and gynecology at Tufts Medical Center, who is researching progesterone and the prevention of preterm labor.
Makena (hydroxyprogesterone caproate), though, isn’t a cure-all for preterm birth. In a 2003 clinical trial of 463 pregnant women who had previously had preterm delivery, some 37 percent of women who had weekly Makena injections — starting between 16 and 21 weeks — delivered prematurely, compared with 55 percent of the control group.
“The magnitude of the effect is modest,’’ said Dr. Michael Greene, chief of obstetrics at Massachusetts General Hospital. “But we don’t have anything that’s better.’’
Hydroxyprogesterone caproate was actually approved by the FDA under the name Delalutin a half-century ago to halt impending miscarriages. It was deemed safe but the manufacturer took it off the market in 2000 because it was eventually shown to be ineffective in stopping miscarriages.
The FDA noted that “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; there was a single report each of blood clot in the lungs (pulmonary embolism) and an infection at the injection site.’’
The agency waited eight years after the original study to approve Makena for the prevention of preterm births because it wanted follow-up data on the children born to women who were on the drug. All of the children of the study participants reached similar developmental targets at 2 1/2 years of age and again at 5 years of age.
KV Pharmaceutical/Ther-Rx Corp., maker of Makena, will continue to study the drug to see whether it provides real clinical benefits in terms of better health outcomes for babies who make it to full term. The drug’s pricing hasn’t yet been set, but it will be available in early March.
The drug has its limits. It hasn’t been shown to be effective at preventing premature births in women who are carrying twins or triplets, Greene said. And it’s only approved for women who already had a preterm birth. Women with shortened cervixes have also been found to benefit from progesterone in the form of suppositories, he said.
Deborah Kotz can be reached at firstname.lastname@example.org.