BioChem Pharma Inc. Triple Combination of 3TC/AZT with Protease Inhibitor Reduces HIV to Undetectable Levels.

MONTREAL--(BUSINESS WIRE)--July 11, 1996--BIOCHEM PHARMA INC.(TSE, ME: BCH NASDAQ: BCHXF ) BioChem Pharma Inc. today announced that the latest data, to be presented in three separate sessions today at the XI International Conference on AIDS in Vancouver, British Columbia, consistently show that combination therapy, built upon the cornerstone combination of 3TCr (Epivir(TM)) plus AZT, is capable of reducing HIV to undetectable levels in the blood.

The results of the three studies show that the triple combination therapy of 3TCr (Epivir(TM)) and AZT with a protease inhibitor reduces viral load to undetectable levels in several different population groups, from very early HIV infection to patients with more advanced disease who had been previously treated with antiretrovirals.

3TCr (Epivir(TM)), AZT and indinavir in AZT-experienced subjects

In one study to be reported today, a three-drug combination of anti-HIV agents, 3TCr (Epivir(TM)), AZT and the protease inhibitor indinavir, resulted in undetectable levels of virus in the blood of HIV positive individuals throughout 44 weeks of treatment.

The study randomized 97 participants to receive either 3TC and AZT, 3TC and AZT in combination with indinavir, or indinavir alone. Median CD4 cell count on entry was 142 cells/mm3.

Median prior AZT experience was 31 months.

Five of six patients who received the triple combination had undetectable levels of HIV in their blood throughout the 44 weeks for which data is currently available. In addition, a median increase of 218 CD4 cells/mm3 over baseline has been shown after 44 weeks of treatment in this group of patients. The triple combination was generally well tolerated.

3TCr (Epivir(TM)), AZT and nelfinavir in antiretroviral therapy-naive subjects

In a second study to be presented today at the conference, preliminary 12-week data on twelve patients with a combination of 3TCr (Epivir(TM)), AZT and nelfinavir, an investigational protease inhibitor, will be reported. None of the patients had received prior antiretroviral treatment for HIV infection before entering the trial. After 12 weeks of treatment, eleven patients had their HIV viral load drop to undetectable levels (less than 25 copies/ml), as measured using the most sensitive assay currently available - the third generation bDNA assay. An average increase of 109 CD4 cells/mm3 was observed. The triple combination therapy was well tolerated. One patient withdrew from the study due to adverse events.

3TCr (Epivir(TM)), AZT and ritonavir in subjects with primary HIV infection

Preliminary data from a third study suggest that treatment with the combination of 3TCr (Epivir(TM)), AZT and ritonavir can also reduce the amount of virus in the blood to undetectable levels. All of the patients in the study were infected with HIV and demonstrated symptoms of primary infection. Primary, or acute, infection describes the initial massive viral replication phase which follows the original infection with HIV and often results in temporary symptoms similar to those associated with influenza. Following treatment with this triple combination, eleven of twelve patients in the study had the virus in their blood reduced to undetectable levels. The twelfth patient had viral load slightly above the detection level. Patients were treated for a period varying between 28 and 240 days. Of the twelve patients in the study, nine identified a precise time of acquiring infection that preceded the onset of symptoms by 15 days, on average. Treatment with the triple drug combination was initiated within an average of 65 days following the onset of symptoms. One patient discontinued ritonavir due to an allergic reaction, but remained in the study receiving the double combination of 3TCr (Epivir(TM)) and AZT.

Commenting on the triple combination therapy data to be presented, Dr. Gervais Dionne, Executive Vice-President, Research and Development, BioChem Pharma stated, "The results obtained from these studies provide support for the view that complete suppression of viral replication may be possible with 3TCr (Epivir(TM))/AZT as cornerstone in combination with a protease inhibitor." "The data also provide support for the view that aggressive treatment, early in the infection, will have a marked clinical benefit," he added.

The detailed results of the meta-analysis evaluating the four 3TCr (Epivir(TM)) pivotal studies will be presented at the conference later today. The data show that the combination of 3TCr (Epivir(TM)) and AZT is associated with a statistically significant decrease in clinical progression compared to the control arms, thus providing the first indication of clinical effectiveness of this dual combination. A meta-analysis, a pooling of data from several trials of a given treatment, is conducted to detect the effect of treatment on an endpoint which may be too rare to analyze in individual trials. It is also conducted to evaluate whether the effect of the treatment on the endpoint is consistent across the trials.

3TCr (Epivir(TM)) plus AZT is the most widely used combination regimen for the treatment of HIV and AIDS in the United States. 3TCr (Epivir(TM)) plus AZT is also the foundation of combination therapy for at least 11 triple-drug regimens currently being studied in clinical trials.

Epivir(TM) is now approved in the U.S, Australia, and Brazil and, under the tradename 3TCr, in Canada, New Zealand, Uruguay and Switzerland. The European Union's Committee for Proprietary Medicinal Products (CPMP) voted in early 1996 in favor of recommending the approval of Epivir(TM) for marketing in Europe and the final decision on marketing approval by the European Commission is awaited.

Under the terms of a license agreement between BioChem Pharma and Glaxo Wellcome, BioChem receives royalties based on sales of 3TCr (Epivir(TM)). Under the terms of the agreement, Glaxo Wellcome has the right to develop, manufacture and sell 3TCr (Epivir(TM)) worldwide, subject to special arrangements in Canada, where a Glaxo Wellcome BioChem partnership is commercializing 3TCr.

BioChem Pharma is an international biopharmaceutical company dedicated to the research, development and commercialization of innovative products for the prevention, detection, and treatment of human diseases. The Company's shares are traded on the Montreal and Toronto Stock exchanges (BCH) and on NASDAQ (BCHXF).

CONTACT: BioChem Pharma Inc.

Christine Lennon, 514/978-7771