WASHINGTON (AP) — Columbia Laboratories said Monday that U.S. health regulators denied approval of its hormone-based gel designed to prevent premature birth. Shares of the small drugmaker plummeted more than 8 percent on the news.

The company said the Food and Drug Administration rejected the drug after concluding it did not meet the minimum standards for effectiveness required of such products. The ruling followed a public hearing last month where a panel of reproductive health doctors voted 13-4 against approval for the progesterone-based gel. The FDA is not required to follow such recommendations, though it often does.

Columbia Laboratories submitted the drug as a treatment to reduce instances of non-full-term births by women with abnormally short cervixes. The company estimates the problem affects 10 to 12 percent of all pregnancies in the U.S. and accounts for 34 percent of all infant deaths in the U.S.