Bio-Technology General And Ares-Serono Sign Major License Agreement For OxSODrol, BTG'S Recombinant Superoxide Dismutase.

ISELIN, NJ--(BUSINESS WIRE)--September 3, 1997--

--BTG To Receive Milestone Payments and License

Fees Of Up To $21 Million--

Bio-Technology General Corp. (NASDAQ:BTGC) today announced that Ares-Serono, a multinational pharmaceutical company based in Geneva, Switzerland, has licensed exclusive worldwide rights, except in the United States, Japan, Canada, and Israel, to OxSODroL(TM), BTG's genetically engineered human superoxide dismutase ("SOD") enzyme, for the treatment of bronchopulmonary dysplasia ("BPD") in premature neonates. The drug is currently in Phase III clinical trials in the U.S.

Under the terms of the agreement, BTG will manufacture and supply recombinant superoxide dismutase to Ares-Serono in the licensed territory and will receive license fees as well as payments linked to the achievement of certain milestones which could total up to $21 million, as well as royalties on all commercial sales of the product.

BPD is a serious lung disease which can occur in premature infants with respiratory distress syndrome (RDS). RDS affects 60-70% of infants born at less than 30 weeks of gestation and often leads to death. Treatment of RDS consists of providing supplemental oxygen with mechanical ventilation and administration of a lung surfactant.

There are more than 30,000 premature neonates born in Western Europe each year diagnosed with RDS. Excess oxygen free-radicals in the neonate lung, which are linked to high concentrations of oxygen due to the mechanical ventilation used in the treatment of RDS, are thought to cause permanent tissue damage leading to BPD in premature babies.

Superoxide dismutase, an enzyme that degrades oxygen free-radicals, has been shown to be protective against such tissue damage in a variety of animal models. Premature neonates have low levels of naturally occurring antioxidant enzymes such as superoxide dismutase, which converts toxic oxygen free-radicals to less toxic hydrogen peroxide and water.

In January 1997, BTG initiated a U.S. multicenter Phase III clinical trial assessing the efficacy and safety of prophylactic administration of superoxide dismutase in the prevention of BPD in premature neonates with RDS. To date, over 120 premature infants have been enrolled in the study, and the company expects enrollment to be completed in the first half of 1998. The duration of treatment is four weeks or less.

Commenting on the agreement, Sim Fass, Chairman, President & CEO of BTG, stated: "Ares-Serono is a highly successful multinational company with an impressive portfolio of drugs in well targeted therapeutic areas. As a manufacturer and marketer of both traditional pharmaceuticals and a growing number of biotechnology drugs, Ares-Serono is an excellent partner for BTG's OxSODrol. We are confident that this relationship will significantly advance our worldwide development program for OxSODrol and we look forward to working closely with Ares-Serono to realize the promise and potential of our product."

"With recombinant superoxide dismutase, we are reinforcing our commitment to neonatology, said Ernesto Bertarelli, Chief Executive Officer of Ares-Serono. It will be the perfect complement to our natural lung surfactant, Curosurf(R). Curosurf(R) is the leading product in Europe for the treatment of RDS in premature infants. As there is currently no approved therapy for BPD, demonstration of clinical efficacy of prophylactic administration of superoxide dismutase would add a vitally important new component to the care of premature newborns. BTG has a proven track record of developing recombinant drugs, and we are looking forward to a fruitful collaboration."

BTG's SOD was licensed to JCR Pharmaceuticals Co. Ltd. of Japan in 1995 for the BPD indication in the Japanese market and is currently in clinical development by JCR.

Bio-Technology General Corp., a leading biopharmaceutical company, develops, manufactures and markets genetically engineered and other products for human health care. Currently, four of BTG's products are marketed in up to 30 countries around the world. Two of these products - Oxandrin(R) and Delatestryl(R) - are marketed in the U.S.

The Ares-Serono Group is a leading Swiss developer and marketer of pharmaceutical products with executive headquarters in Geneva, Switzerland. World leader in the treatment of infertility, Ares-Serono is also active in the fields of growth, wasting and multiple sclerosis/immunology. With nine recombinant products under development, Ares-Serono is one of today's biotechnology leaders. Three of these products are already marketed for various indications. Ares-Serono operates subsidiaries and manufacturing facilities in 30 countries. Shares of Ares-Serono S.A., the holding company of the group, are traded on the Swiss stock exchange.

CONTACT:Investor Relations Contact

Don Weinberger Leah Berkovits

STRATEGIC GROWTH INTERNATIONAL BIO-TECHNOLOGY GENERAL CORP.

516-829-7111 732-632-8800