FDA questions effectiveness of Gestiva at preventing preterm labor

FDA in a review of Adeza’s experimental preterm labor prevention drug Gestiva said the drug seems to reduce deliveries before 37 weeks’ gestation but not births before 32 or 35 weeks’ gestation, according to documents posted Monday on the agency’s Web site, the Wall Street Journal reports (Corbett Dooren, Wall Street Journal, 8/29).

Births before 37 weeks’ gestation are considered premature, but most cases of death and health problems among premature infants occur among infants born before 32 weeks’ gestation, the AP/Contra Costa Times reports. FDA documents reviewing Gestiva say the results of a clinical trial do not show “statistically persuasive” evidence that the drug—injected weekly from between 16 and 20 weeks’ gestation to either the 36th week or birth—reduces the number of births before either 32 or 35 weeks’ gestation. However, Gestiva’s apparent effectiveness in preventing births before 37 weeks’ gestation is “noteworthy” because most premature infants are born after 32 weeks’ gestation (Bridges, AP/Contra Costa Times, 8/28). FDA’s review also says the drug appears to increase the risk of miscarriage and might increase the stillbirth rate. An independent advisory panel on Tuesday plans to consider Adeza’s application, and FDA asked the panel to recommend if further studies on Gestiva are needed.

Preterm Labor Drugs

Gestiva would be the only FDA-approved drug to prevent preterm labor if the company’s application is accepted, the Journal reports (Wall Street Journal, 8/29). The American College of Obstetricians and Gynecologists in 2003 recommended using the hormone progesterone to prevent premature deliveries for women with histories of early labor, the San Jose Mercury News reports. FDA said unapproved progesterone compounds are “being used widely” (Johnson, San Jose Mercury News, 8/29). A preterm labor drug containing the same ingredients as Gestiva was approved by the agency in 1956, but approval was withdrawn in 2000 after its manufacturer stopped producing it. According to Dow Jones, FDA granted Gestiva priority-review status, which cuts the approval process by four months, saying the need for an approved preterm labor drug is “particularly acute.” Adeza in a release said it expects the agency to decide on its application by Oct. 20 (Corbett Dooren, Dow Jones, 8/28). About 12% of U.S. infants born in 2002 were premature, an increase of 29% from 20 years ago, according to FDA (AP/Contra Costa Times, 8/28).