FDA Okays Birth Control Pill to Eliminate Menstrual Cycles

ROCKVILLE, Md., May 23 -- The FDA has approved the first continuous use oral contraceptive for prevention of pregnancy -- a pill that will eliminate a woman's monthly menstrual cycle.

The new oral contraception willl be marketed in 28-day pill packs under the brand name Lybrel. Developed by Wyeth, Lybrel contains 90 mcg of levonorgestrel and 20 mcg of estrogen.

Unlike other oral contraceptive regimens that include four to seven placebo or off-pill days in order to stimulate a menstrual cycle, the new pill continuously suppresses the production of hormones so that women would not have a scheduled menstrual period.

The FDA said, however, that women who use Lybrel are likely to have unplanned, breakthrough, unscheduled bleeding, or spotting.

At an FDA briefing Scott Monroe, M.D., of the agency's Center for Drug Evaluation and Research said about half the women in clinical trials, which included more that 2,400 women ages 18 to 49, stopped taking the drug because of unscheduled bleeding or spotting.

Of the remaining women who completed the trials, only 30%- to 35% had no bleeding or spotting. Bleeding and spotting occurred an average of four to five days per 28-day cycle, which is the same as for women on traditional birth control pills and even for women who don't take birth control pills at all.

Pressed for more detail on the number of women who dropped out of the studies, Dr. Monroe said, "The number of people who have amenorrhea -- no bleeding or spotting-- at the end of 13 cycles is about 60%."

The FDA said physician and patients considering the use of the new pill should weigh the convenience of having no menstruation against the inconvenience of unscheduled bleeding or spotting.

Dr. Monroe said that the approval of Lybrel "concludes a comprehensive review process," but because there are no embolic event data on the drug-a risk with approved oral contraceptives--the FDA has asked Wyeth for a postmarketing safety study.

He said that the primary endpoint of the clinical trials was contraceptive efficacy. The postmarketing phase IV study will allow the FDA to "to see whether there are any long-term effects," but he added that the FDA did not "suspect any surprises in terms of long-term use of this product."

Because the pill eliminates regular periods, it may be difficult for women to recognize whether they have become pregnant, the FDA said. Women should take a pregnancy test if they believe they may be pregnant. Women should also discuss contraceptive use, and the precautions and warnings for use of the drug product, with their doctors or other professionals.