A drug to help women carry their babies to term that is awaiting federal approval doesn’t appear to delay the earliest preterm births most often linked to death and serious health problems, according to federal documents released Monday.
The results of a single clinical trial were not “statistically persuasive” in suggesting that the injectable drug, Gestiva, reduced births before either 32 or 35 weeks’ gestation, Food and Drug Administration documents show.
However, the drug does appear to reduce births before the 37th week, considered the cutoff point for a newborn to be considered premature, study results suggest. Adeza Biomedical Corp. said in FDA filings that weekly injections of Gestiva lead to a “substantial reduction” in preterm births among women most at risk.
The FDA said even that effect could be of “noteworthy” importance to public health since a large number of preterm births occur after 32 weeks.
Babies born anytime after 32 weeks generally survive without serious, long-term developmental problems. Babies born before 32 weeks make up just 2 percent of births, but account for most cases of death and problems among preemies.
The U.S. premature birth rate grew to 12 percent in 2002, a 29 percent increase over the previous two decades, according to the FDA. The rate has increased as more older women get pregnant and the use of fertility treatments grows, the FDA said.
The FDA released the documents ahead of a meeting Tuesday by an outside panel of experts that is expected to recommend whether the agency should approve the drug application filed by the Sunnyvale, Calif.-based company.
One concern is that the drug may increase the miscarriage and stillborn rate, the FDA said. Among the questions being asked of the panel is whether further study of the drug is needed. The FDA generally requires pharmaceutical companies to submit results from at least two clinical trials.
Gestiva would be the only FDA-approved drug to prevent preterm birth. Some specialty pharmacies already make and sell the drug without federal approval.
The FDA originally approved the drug in 1956 to prevent spontaneous abortions. FDA withdrew approval in 2000 after its manufacturer stopped selling it.
The drug is intended for use in women who previously have had at least one preterm birth. It is meant to be injected weekly between the 16th and 20th weeks of pregnancy through the 36th week, or birth.