Columbia Laboratories' Announces the Conclusion of Its Multicenter Phase III Study for Its AIDS Fighting Spermicide Advantage-S.

Business Editors/Health & Medical Writers

MIAMI--(BUSINESS WIRE)--May 9, 2000

Results to be presented at the XIII International

AIDS Conference July 10-14, 2000

Columbia Laboratories (AMEX:COB) today announced that patient enrollment had been completed and final patient visits initiated in the phase III multi-center, randomized, placebo controlled double blind study of Advantage-S(r) in women at high risk of HIV infection. Analysis of the data is expected by the end of June and the results will be presented on July 10-14, 2000 in Durban, South Africa at the XIII International AIDS Conference.

Advantage-S is currently being sold in the United States, Canada and China as a spermicide. Assuming successful completion of the study, Columbia plans to submit an NDA later this year in the United States to amend its labeling to include a claim that Advantage-S helps prevent the transmission of HIV and other sexually transmitted diseases. A similar file will be submitted to EMEA in Europe as soon as the data is fully analyzed. Under current FDA regulations, the Company believes it will receive a priority review which should lead to approval within six months of submission. Columbia is also working to ensure that Advantage-S is made available, as soon as possible, to women in Africa and Asia in order to help stem the tide of the AIDS epidemic and prevent the transmission of HIV to women, their offspring and partners.

In 1999 there were 14.8 million women with AIDS and their number is growing by more than 2 million each year. The development of safe and effective microbicides capable of preventing the transmission of HIV (the AIDS virus) and other sexually transmitted organisms in the vagina has been Columbia's priority. Columbia has been working for the past six years to demonstrate that only with our patented bioadhesive delivery system can nonoxynol-9 reduce the transmission of HIV.

The activity of nonoxynol-9 is based on the disruption of cell membranes, of both sperm and microorganisms. Nonoxynol-9, particularly at high doses, can cause disruption of vaginal epithelial cells that can lead to irritation. The use of the bioadhesive technology to lower the dose helps minimize this problem. "The bioadhesive polymer maintains greater contact between the anti-STD agent and the infectant for a much greater period of time, enabling a lower concentration to act longer on the infectant, when compared to currently available commercial applications containing N-9. Such delivery will enable a safe and non-irritating decrease in the risk of infections with STD's including HIV" (Anti-STD: Patent No.5,667,492 (expires 10/7/14); and continuation application no. 08/870,653, filed June 6, 1997 (pending). There are corresponding patents in the rest of the world. Only the polycarbophil bioadhesive technology potentiates the action of nonoxynol-9 on STD's and at the same time minimizes the potential for irritation.

A previously published randomized placebo-controlled safety study (AIDS 1998, 12:433-437) of this bioadhesive vaginal gel among 534 healthy volunteers demonstrated its safety. The product was administered once a day for 14 days. Overall epithelial disruption occurred in 3.5% of the active group and 3.4% of placebo users. The conclusion of the study was that Advantage-S was safe and associated with minimal toxicity when used once daily.

Columbia Laboratories, Inc. is a U.S.-based international pharmaceutical company dedicated to research and development of women's health care products, including those intended to treat infertility, dysmenorrhea, endometriosis, hormonal deficiencies and the prevention of sexually transmitted diseases. Columbia's products primarily utilize the company's patented bioadhesive delivery technology.

This press release contains statements which constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Those statements include statements regarding the intent, belief or current expectations of the company and its management team. Prospective investors are cautioned that any such forward-looking statements are note guarantees of future performance and involve risks and uncertainties, and that actual results may differ materially from those projected in the forward-looking statements. Such risks and uncertainties include, among other things, the favorable outcome of the multicenter phase III study, timely filing and approval of Columbia's U.S. and foreign regulatory filings with respect to Advantage-S, competitive economic, and regulatory factors in the pharmaceutical and health care industry, general economic conditions and other risks and uncertainties that may be detailed, from time-to-time, in Columbia's reports filed with the Securities and Exchange Commission.