CytRx Announces Phase I HIV Vaccine Clinical Trial Enrollment Completion

LOS ANGELES -- CytRx Corporation, Advanced BioScience Laboratories (ABL) and the University of Massachusetts Medical School (UMMS) today announced the completion of enrollment of healthy volunteers in a three-arm Phase 1 clinical trial for a novel HIV DNA vaccine.

The primary objective of the Phase 1 clinical trial is to determine the safety and tolerability of different dosages and routes of administration of the DNA vaccine, and a fixed dosage and route of administration of an HIV protein boost. The vaccine strategy is to assess in human volunteers whether a DNA vaccine with a protein boost can stimulate both antibody and T-cell immune responses to the virus as previously demonstrated in animal models. To date, the vaccine has been well tolerated in humans.

"We reached this significant recruitment milestone six months ahead of our internal timetable" stated Steven A. Kriegsman, president and chief executive officer of CytRx. "We had previously announced that dosing would be completed by the end of 2005. Based on clinical investigators' efforts at UMMS to quickly complete enrollment, we now expect dosing to be completed by the end of July 2005, six months ahead of schedule."

CytRx, ABL and UMMS anticipate that preliminary safety, tolerability and limited immunogenicity data from this trial will be presented by the clinical investigators later this year.

"It is our hope that the results from this clinical trial will provide useful information regarding the immune response to this DNA vaccination as well as the effect of using protein as a vaccine boost," said Jeff Kennedy, MD, assistant professor of medicine at UMMS and the principal investigator of the clinical trial.

The trial consists of three groups: Group A received the DNA vaccine intradermally, and Groups B and C received the DNA vaccine intramuscularly, with Group C receiving a six fold higher DNA dose compared with Groups A and B. This trial is designed to test the ability of different routes of administration and doses of the vaccine on immune responses to the antigens incorporated in the vaccine. Participants are monitored at regular intervals for adverse events as well as antibody responses and cell-mediated immune responses, which are the ability of the vaccine to cause the host to produce T-cells that kill HIV-infected cells.

It is projected that Groups A and B will complete the five inoculations required by the protocol by May 2005 and data from ongoing assays of immune response are planned to be available in the third quarter of 2005. Group C is projected to complete DNA vaccination requirements in the third quarter of 2005.

The HIV vaccine formulation created by researchers at UMMS and ABL is a polyvalent vaccine based on multiple strains of HIV collected directly from infected people living in different parts of world, representing five different strains of the virus. The secondary objectives of the trial will test whether the approach can generate cross-clade anti-HIV immune response in humans. The vaccine contains elements from selected HIV genes, not the live virus and, therefore, individuals receiving inoculations cannot get HIV from the vaccine.

The HIV vaccine is exclusively licensed to CytRx by UMMS and ABL. To date, the HIV vaccine project has been funded under a five-year HIV Vaccine Design and Development Team contract from the National Institute of Allergy and Infectious Diseases (NIAID), part of the NIH.

Source: CytRx Corporation