Indevus Pharmaceuticals Announces PRO 2000 Found to Show Promise in Large HIV Prevention Study
Results of NIH-sponsored Clinical Trial to be Presented at Retrovirus Conference
LEXINGTON, Mass., Feb. 9 /PRNewswire-FirstCall/ -- Indevus Pharmaceuticals, Inc. (Nasdaq: IDEV) announced today that a National Institutes of Health (NIH)-sponsored clinical study found that participating women who received PRO 2000, the Company's candidate vaginal microbicide for HIV prevention, had an approximately 30% lower risk of acquiring HIV infection than women who received a placebo or no vaginal product. All women participating in the study were offered free condoms and safer-sex counseling. This is the first trial to suggest any microbicide may prevent male-to-female sexual transmission of HIV although the beneficial effect did not reach statistical significance. The results will be presented today at the 16th Conference on Retroviruses and Opportunistic Infections in Montreal.
"We are extremely excited with the results of this trial," stated Glenn L. Cooper, M.D., chairman and chief executive officer of Indevus. "Though not conclusive, these results provide encouragement that PRO 2000 may offer a female-controlled method that can be used to protect against the sexual transmission of HIV.
"In addition to the HPTN 035 trial, we are awaiting results from the MRC-sponsored trial which will provide data on nearly 10,000 women," continued Dr. Cooper. "These results should be available by the end of 2009."
The HIV Prevention Trials Network (HPTN) 035 trial was a multi-national, randomized, placebo-controlled trial to assess the safety and effectiveness of PRO 2000 and another investigational vaginal microbicide (BufferGel(R), ReProtect, Inc.) in preventing HIV infection in women. The trial was sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), a component of the NIH, and conducted by the NIH-funded Microbicide Trials Network (MTN) at seven clinical centers in Malawi, Zimbabwe, South Africa, Zambia, and the United States.
The trial was initiated in February 2005 and enrolled approximately 3,100 eligible, HIV-uninfected women, all of whom provided written informed consent. Enrolled participants were randomly assigned to one of four arms: PRO 2000 gel (0.5% strength), BufferGel, a placebo gel, or no gel. Women enrolled in the three gel arms were asked to apply the assigned study product vaginally up to one hour before each act of sexual intercourse. The gel arms were double-blinded so that neither the participant nor the study staff knew the identity of the assigned study product. Women in all four arms received a standard-of-care HIV prevention package, which included free male condoms, risk-reduction counseling, and treatment of sexually transmitted infections. Participants were followed for 12-30 months (20 months on average), depending on when they entered the study.
A total of 194 new HIV infections occurred among study participants over the course of the trial. Of these, 36 occurred in the PRO 2000 arm, 54 in the BufferGel arm, 51 in the placebo arm, and 53 in the no-gel arm. Based on these data, PRO 2000 was 30 percent effective (approximately 33 percent effectiveness would have been considered statistically significant). The adverse event profile was similar in all four arms, indicating that 0.5% PRO 2000 is safe for vaginal use. A full analysis of the trial data is underway.
The study was conducted in communities where the background rate of HIV infection is high. Participants who became infected with HIV during the trial were referred to local HIV care and support services. Where possible, infected participants were invited to participate in Microbicide Trials Network (MTN) 015, a clinical study examining the nature of HIV progression and treatment response in HIV-positive women who had been using a topical microbicide or oral antiretrovirals as an HIV preventive measure when they acquired HIV infection.
A second large trial testing the safety and effectiveness of the 0.5% dose of PRO 2000 is currently underway. This trial is being sponsored by the United Kingdom's Medical Research Council (MRC) and conducted by the Microbicides Development Programme (MDP), an international partnership of researchers established to develop microbicides for the prevention of HIV transmission. Study MDP 301 is a multi-national, randomized, double-blind, placebo-controlled Phase III trial designed to examine the safety and effectiveness of PRO 2000 in preventing HIV infection in women. As in the HPTN 035 trial, all participants receive free condoms, risk-reduction counseling, and treatment for sexually transmitted infections. Approximately 9,400 women have been enrolled at study sites in South Africa, Tanzania, Uganda, and Zambia. The trial is expected to be completed during the summer of 2009.
Should PRO 2000 be shown conclusively to be safe and effective, Indevus intends to seek worldwide marketing approvals, and plans to work with government agencies and other organizations to help ensure affordable access to the product in resource-limited settings where the need is greatest.
According to statistics from UNAIDS and the U.S. Centers for Disease Control and Prevention, nearly half of the 33 million people living with HIV/AIDS worldwide are women. Most HIV infections in women are due to heterosexual intercourse. Moreover, women are twice as likely as their male partners to acquire HIV during sex, due in part to biological factors that make women more vulnerable. Although correct and consistent use of male condoms has been shown to prevent HIV infection, women often cannot negotiate condom use with their male partners. A safe and effective vaginal microbicide could offer a readily available approach for many women who cannot simply rely on condoms or abstinence as methods for protecting themselves from HIV. Even a partially effective microbicide could have a profound impact on the dynamics of HIV transmission. According to mathematical modeling conducted by the London School of Hygiene and Tropical Medicine, 2.5 million HIV infections could be averted over three years if a microbicide with 60 percent effectiveness were used in 73 low-income countries.
Indevus Pharmaceuticals, Inc. is a specialty pharmaceutical company engaged in the acquisition, development, and commercialization of products to treat conditions in urology and endocrinology. The Company's approved products include SANCTURA(R) and SANCTURA XR(TM) for overactive bladder, VANTAS(R) for advanced prostate cancer, SUPPRELIN(R) LA for central precocious puberty, and DELATESTRYL(R) to treat male hypogonadism. The Indevus development pipeline contains multiple compounds within the Company's core therapeutic areas in addition to several partnered or partnerable programs. The most advanced compounds in development include, VALSTAR(TM) for bladder cancer, NEBIDO(R) for hypogonadism, PRO 2000 for the prevention of infection by HIV and other sexually-transmitted pathogens, the octreotide implant for acromegaly and carcinoid syndrome, and pagoclone for stuttering.
PRO 2000 (a naphthalene sulfonate polymer) is under development as a topical vaginal microbicide to prevent the sexual transmission of HIV and other sexually transmitted diseases. Laboratory studies have shown that PRO 2000 is active against HIV, herpes simplex virus, chlamydia and the bacterium that causes gonorrhea. Vaginally applied PRO 2000 has been found to afford protection in mouse models for genital herpes infection and gonorrhea, and in a simian model for vaginal HIV infection. Prior to initiation of the HPTN 035 trial, PRO 2000 had undergone extensive safety testing in several clinical trials involving women and men in the United States, Europe, Africa and India.
Forward Looking Statements
Except for the descriptions of historical facts contained herein, this press release contains forward-looking statements that involve risks and uncertainties that could cause the Company's actual results and financial condition to differ materially from those anticipated by the forward-looking statements. These risks and uncertainties are set forth in the Company's filings under the Securities Act of 1933 and the Securities Exchange Act of 1934 under "Risk Factors" and elsewhere, and include, but are not limited to: dependence on the success of SANCTURA(R), SANCTURA XR(TM), NEBIDO(R) , VANTAS(R) and SUPPRELIN(R) LA; need for additional funds and corporate partners, including for the development of our products; effectiveness of our sales force; competition and its effect on pricing, spending, third-party relationships and revenues; dependence on third parties for supplies, particularly for histrelin, manufacturing, marketing, and clinical trials; risks associated with being a manufacturer of some of our products; risks associated with contractual agreements, particularly for the manufacture and co-promotion of SANCTURA and SANCTURA XR and the manufacture of NEBIDO, VANTAS, SUPPRELIN LA and VALSTAR(TM); reliance on intellectual property and having limited patents and proprietary rights; dependence on market exclusivity, changes in reimbursement policies and/or rates for SANCTURA, SANCTURA XR, VANTAS, SUPPRELIN LA, DELATESTRYL(R) and any future products; acceptance by the healthcare community of our approved products and product candidates; uncertainties relating to clinical trials, regulatory approval and commercialization of our products, particularly SANCTURA XR, NEBIDO, and VALSTAR; product liability and insurance uncertainties; risks relating to the Redux-related litigation; history of operating losses and expectation of future losses; uncertainties relating to controls over financial reporting; valuation of our Common Stock; risks related to repayment of debts; risks related to increased leverage; general worldwide economic conditions and related uncertainties; and other risks. Indevus undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise.