Enzo Biochem Reports Preclinical Findings At International AIDS Conference.

VANCOUVER, Canada--(BUSINESS WIRE)--July 10, 1996--Enzo Biochem (ASE:ENZ) of Famingdale, N.Y. announced today that its scientists and collaborators have produced human immune cells that are completely and stably resistant to multiple challenges of HIV.

This approach is targeted to provide the medical community with a powerful new weapon in the fight against AIDS. The Company said that following completion of the preclinical studies, it plans to move ahead towards the development of protocols for human clinical studies.

These findings were released today at the 11th International Conference on AIDS in a presentation by Norman Kelker, Ph.D., Senior Vice President of Enzo and a participating scientist at the conference. The studies show that CD4+ cells, that are normally sensitive to HIV-1 infection, are protected when treated with Enzo's antisense construct. Resistance to HIV-1, which was shown to correlate with production of antisense RNA by the cells, could lead to restoring immune competence in patients, even in the presence of challenge by HIV.

"We have now successfully demonstrated that we can create CD4+ cells that are resistant to HIV-1 and that maintain their resistance to the virus over a prolonged period," said Dr. Kelker. "This is a very important step in moving towards the development of an effective clinical product for HIV therapy. We believe that our antisense therapy alone, or in combination with already established protocols, can become an effective and widely applied treatment for HIV-infected individuals."

Enzo's approach utilizes methods to overcome effects due to the variability and mutability of the virus and to localize the antisense in the cell nucleus where its antiviral activity is most effective. The Company noted that, unlike currently used treatments aimed at viral reverse transcriptase or protease, its antisense approach is designed not to require repeated applications.

According to the report, which presents results from a more than year-long study, Enzo's therapeutic approach is aimed at inhibiting expression of HIV-1 genes by antisense RNA. The approach is gene specific and does not affect cellular genes. Thus, the establishment of such antisense-producing immune cells in the patient could protect against collapse of the immune system in AIDS patients. The therapy would be applied to immune cells removed from the patient and altered ex vivo, that is, outside the body, by the introduction of antisense producing genes. Altered cells reimplanted in the patient are expected to propagate HIV-resistant immune cells.

Enzo Biochem is engaged in the research, development and manufacture of innovative health care products based on molecular biology and genetic engineering techniques, and in providing diagnostic services to the medical community.

CONTACT: Barry Weiner, 212/856-0876

Steve Anreder, 212/421-4020