The Lea's Shield is denied FDA Approval
by Lena Kuo
On October 21, 1996, the FDA advisory panel for Ob/Gyn Devices advised against the pre-market approval (PMA) of the Lea's Shield, a new contraceptive device. The Lea's Shield is a barrier method which, like the diaphragm, covers the cervix to prevent pregnancy and possibly sexually transmitted diseases which infect through the cervix, such as Chlamydia and gonorrhea. The Lea's Shield is constructed from soft silicone rubber and stays in place by filling the area surrounding the cervix. The device is designed so that one size fits all women, giving it the potential to eventually be available in drug stores. It might also be preferable to the diaphragm for women who are allergic to latex, experience repeated urinary tract infections or who have difficulty inserting the device correctly.
The manufacturers of the Lea's Shield, Yama Inc., applied for PMA under 1990 'DA guidelines which expedite approval barrier methods that prevent the spread of sexually transmitted diseases, especially HIV. In order to speed the approval of such barrier methods, the 1990 FDA guidelines expedites the research necessary for PMA, calling for a non-randomized, 6 month study with 200 participants to determine the safety and efficacy of the device. The research group for the Lea's Shield, Contraceptive Research and Development (CONRAD), based its evaluation of the Lea's Shield on these "fast track" guidelines.
Although CONRAD designed its study according to guidelines outlined by the FDA, the advisory panel concluded that the research data were insufficient in determining the efficacy of the device. The CONRAD study determined that Lea's Shield is 91% effective in preventing pregnancy, a result which is as good or better than other women-controlled barrier methods. Interestingly, the study also found that the Shield was nearly as effective, 87%, even without spermicide. Ironically, it was this positive finding that interfered with approval. Because the manufacturer plans to advise women to use spermicide, the FDA refused to consider data from women who used the device with a placebo gel. From the FDA's point of view the Lea's Shield study was "too small." Although some members of the Advisory Panel argued for conditional approval with written informed consent, FDA officials stated that they were not comfortable with that option and the Panel members voted 7-1 against approval.
The Network strongly supported the approval of the Lea's Shield. Prior to the FDA advisory panel meeting, the Network organized a policy briefing on the Lea's Shield. We discussed the importance of female barrier devices that prevent the transmission of sexually transmitted diseases. Lisa Cox, Network program director, testified at the FDA meeting, stressing the need for female-controlled barrier devices that not only prevent pregnancy but also may offer protection against sexually transmitted diseases. In addition, the Network urged the FDA to adhere to 1990 guidelines that expedite approval for female barrier devices.These guidelines represent a sensible middle ground between traditional requirements for large, long-term randomized trials and 510K (substantial equivalence) approval which requires no efficacy data. Lisa Cox argued that the 1990 guidelines offer reasonable safety and efficacy data, while speeding greatly needed, safe contraceptive devices to women.
What is next for the Lea's Shield? The National Institutes of Health may sponsor additional efficacy studies necessary for future approval. However, American women will not see this barrier device on the market for quite a while. Until then, the Network will continue to support the FDA approval of safe, effective female-controlled barrier devices.
Please contact the Clearinghouse for a free copy of the Network's testimony.
Lena Kuo was a fall intern.