Intravaginal use of topical immune booster tested for cervical dysplasia. (May Spur Spontaneous Resolution of Lgsil).

A topical drug that boosts the immune system and is delivered intravaginally may have a role in treating low-grade cervical dysplasia.

The prototype agent of this kind, imiquimod (Aldara), has been tested in a recently completed phase II study that included 130 women with low-grade squamous intraepithelial lesions (LGSIL). The study was sponsored by the drug's manufacturer, 3M.

A completed analysis of the results is not expected until next year. In the meantime, several gynecologists have used imiquimod to treat these types of patients on an anecdotal basis, a step that 3M cautions against.

"We're aware of the anecdotal experience, but 3M does not in any way, shape, or form recommend that physicians try this on their own. We recommend the opposite," said Nancy M. Klinger, a senior clinical research specialist with 3M in St. Paul.

In fact, even if the results of the phase II study are positive, 3M currently does not plan to pursue development of this indication for imiquimod, Ms. Klinger said in an interview. The company is developing additional topical immune-response modifiers that will likely be the eventual focus of more extensive clinical studies.

Safety is the main concern with imiquimod, said Dr. Ken Trofatter, a professor of ob.gyn. at the University of Minnesota in Minneapolis and medical monitor for the imiquimod study. Based on experience using the drug to treat external anogenital warts (the approved indication), expected adverse events in the cervical dysplasia study included local site reactions and systemic, flulike symptoms.

"We stopped the [phase II] study a little early because we saw a little too many local reactions," Ms. Klinger said. "We'll focus on new molecules where that doesn't happen. It's very clear to us that this has to be a product that is very, very safe."