Mitsui Ventures 三井ベンチャーズ(MVC、MCVP) ベンチャーキャピタル ベンチャー 三井物産 起業

NEWS 2004

[11/23/2004]

HIV Drug Candidate, PA-457, Exhibits Potent Anti-HIV Activity Following a Single Dose in HIV-infected Patients

Full Results to be Presented at the 12th Conference on Retroviruses and Opportunistic Infections, February 2005

GAITHERSBURG, MD, November 23, 2004 /PRNewswire/ -- Panacos Pharmaceuticals, Inc. today announced positive preliminary results from a proof-of-principle Phase I/II clinical trial of the Company’s lead HIV drug candidate, PA-457. In that study, PA-457 was administered as a single oral dose to HIV-infected patients who were not on other therapy, in order to determine the pharmacokinetics and antiviral effect of the compound. Several different dose levels were tested in addition to placebo and the level of virus in the plasma, known as the viral load, was measured before and at intervals after treatment in each patient. A significant reduction in viral load, of up to approximately 0.7 log10, was seen in patients receiving the higher dose levels.

The study has been selected for oral presentation at the 12th Conference on Retroviruses and Opportunistic Infections to be held in Boston, MA during February, 2005, at which time a detailed description of the clinical trial and results will be provided. The Company will also present data from a recently completed Phase Ib clinical trial of PA-457 at the Conference. In that trial, PA-457 was administered orally once a day for 10 days to uninfected volunteers. PA-457 was well tolerated and plasma concentrations of the compound reached levels significantly greater than those predicted to provide a therapeutic benefit in HIV-infected patients.

Dr. David E. Martin, Panacos’ VP, Drug Development, commented: “The results of the proof-of-principle study in HIV-infected patients are extremely encouraging and provide strong validation for PA-457’s further development. A reduction of up to 0.7 log10 in HIV RNA following just a single dose should translate into a much greater antiviral effect when PA-457 is administered on a daily basis for several days or more.”

PA-457 is the first in a new class of oral HIV drugs discovered by Panacos scientists that inhibit virus maturation, the last stage of the virus life cycle. It is designed to combat drug resistance, which occurs in most HIV patients treated with currently available drugs. Resistance to existing drugs is the most pressing problem in HIV therapy and the leading cause of treatment failure. PA-457 works by a mechanism completely different from that of any approved drug or other drug in development, by blocking a key step in the processing of a viral core protein called capsid. Preclinical studies have shown that PA-457 retains full activity against drug-resistant virus, is effective in an animal model of HIV infection and should be suitable for use in combination therapy with other drugs.

The Company is about to initiate a key multiple dose Phase IIa study in HIV-infected patients with results expected in the first half of 2005. This study is designed to determine the antiviral effect of multiple once-daily doses of PA-457 in patients who are not on other antiretroviral therapy.

About Panacos

Panacos Pharmaceuticals is engaged in the discovery and development of small molecule oral drugs for the treatment of HIV and other major human viral diseases. Panacos’ proprietary discovery technologies focus on novel targets in the virus life cycle, including virus fusion and virus maturation, the first and last steps of viral infection.

On June 2, 2004, Panacos Pharmaceuticals entered into a definitive merger agreement with V.I. Technologies, Inc. (Nasdaq: VITX), a biotechnology company dedicated to developing novel anti-infective technologies. The terms of the merger were amended on November 5, 2004, November 29, 2004 and December 8, 2004. The transaction is expected to close in the first quarter of 2005 and is subject to the approval by shareholders of both companies and other customary closing conditions.

More information on Panacos is available at www.Panacos.com.

http://www.panacos.com/