TNX-355 Among HIV Therapies Highlighted at International Meeting of the Institute of Human Virology

HOUSTON -- Tanox, Inc. medical director Dr. Stanley Lewis recently presented findings from the Phase I clinical trial of TNX-355 for the treatment of human immunodeficiency virus (HIV) at the 2004 International Meeting of the Institute of Human Virology (IHV) in Baltimore, Md.

In a conference track titled New Approaches to HIV Therapy, Lewis discussed the safety and anti-HIV activity of TNX-355 in testing conducted in HIV-infected patients during the trial.

TNX-355 is a humanized, non-immunosuppressive anti-CD4 monoclonal antibody that works by blocking the ability of HIV to enter CD4 cells.  It is one of a new class of drugs called viral entry inhibitors.  Entry inhibitors have the potential to offer significant advantages to treatment-naive and treatment-experienced patients over some currently available therapies due to the low risk of cross-resistance.

The annual IHV meeting is highly regarded in the scientific community as a central forum to discuss viral diseases, said Lewis.  There is significant interest among researchers and clinicians regarding the potential of antiviral entry inhibitors for HIV treatment, which are viewed by many experts as the next step in the evolution of anti-HIV therapy.

The Phase Ib clinical trial for TNX-355 was completed in 2003.  Results from the trial indicated that TNX-355 appeared to be safe and well tolerated.  The drug demonstrated a transient, but clinically significant, reduction in viral load, with no CD4 cell depletion.  TNX-355 received Fast Track status from the U.S. Food and Drug Administration (FDA) in October 2003.

A Phase II clinical trial for the drug began in May 2004.  The study is a three-arm, double-blind, placebo-controlled study, which will enroll approximately 80 patients.  All patients will be anti-retroviral therapy-experienced, and will receive optimized background therapy during the study, in addition to one of two doses of TNX-355 or placebo.  Data from the trial is expected in the second half of 2005.

Source: Tanox, Inc.