* Alexion Pharmaceuticals Inc., of New Haven, Conn., said results of a Phase I/II trial of its lead drug, C5 Inhibitor 5G1.1-SC, for preventing tissue damage during cardiopulmonary bypass surgery showed the drug was well tolerated and demonstrated efficacy. The product, a single-chain antibody, is designed to inhibit activation of the body's complement cascade, which is part of the immune system and can trigger damaging inflammation. The company plans to conduct a Phase IIa study followed by a Phase II trial.

* Cellegy Pharmaceuticals Inc., of Foster City, Calif., completed a $3.8 million private placement of approximately 1.5 million shares to a group of investors. The company also has reacquired the rights to a skin repair technology that had been licensed to Neutrogena Corp., a subsidiary of Brunswick, N.J.-based Johnson & Johnson.

* Cypress Bioscience Inc., of San Diego, said an independent data safety and monitoring board recommended continuation of a pivotal trial of the company's Prosorba column for rheumatoid arthritis after a preliminary look at patients' responses to the device. Prior to the start of the trial, Cypress asked the independent board to examine the study and recommend either continuing or stopping based on projections for a 20 percent or greater response rate. Prosorba is on the market for treatment of idiopathic thrombocytopenic purpura, an immune-mediated bleeding disorder. The device is a disposable filter that uses protein A to remove circulating immune complexes, such as antibodies and antigens, that are believed to be responsible for autoimmune diseases.

* Gensia Laboratories Inc., a wholly owned subsidiary of San Diego-based Gensia Sicor Inc., has inked a two-year agreement to supply 10 products to 160 U.S. hospitals and institutions within the Catholic Materials Management Alliance organization. Financial terms were not disclosed.

* Geron Corp., of Menlo Park, Calif., entered an agreement with Synteni Inc., of Palo Alto, Calif., for use of the latter's gene expression microarray technology for drug discovery targeting age-related disorders. Synteni's technology will be used to evaluate gene expression patterns in senescent cells, those that have reached the end of their capabilities to divide and therefore begin to die.

* Human Genome Sciences Inc., of Rockville, Md., and SmithKline Beecham plc, of London, streamlined their 1993 agreement on development of diagnostics based on the former's identification of genes. The amended deal gives Human Genome Sciences rights to market diagnostics that support drugs it is developing. The new agreement also simplifies procedures for SmithKline to outlicense diagnostic products and grants Human Genome Sciences royalties on sales. The companies said the amendments do not affect their drug discovery collaborations.

* Oncogene Science Inc., of Uniondale, N.Y., extended for 15 months its collaboration with Hoechst Marion Roussel AG, of Frankfurt, Germany, for drug discovery targeting Alzheimer's disease, atherosclerosis, metabolic disorders and rheumatoid arthritis. The extended agreement expires March 31, 2002. Financial terms were not disclosed. The drug discovery collaboration is based on Oncogene's technology for regulating gene expression.

* NeoTherapeutics Inc., of Irvine, Calif., said data from a 10-patient, dose-ranging Phase I/II trial of its drug AIT-082 for Alzheimer's disease showed the compound was orally absorbed, produced no serious side effects and improved memory function. In the study, the 60 percent of patients who received the lowest doses demonstrated improved memory, while 80 percent in the placebo group experienced decreases in memory. The company said the efficacy results were statistically significant. NeoTherapeutics also said that at the highest doses no improved memory was exhibited. The drug is a small molecule designed to boost levels of neurotrophic factors for regeneration of nerve cells, which when damaged cause loss of memory.

* Repligen Corp., of Needham, Mass., identified a small molecule compound that inhibits basic fibroblast growth factor and vascular endothelial growth factor involved in angiogenesis, the process of blood vessel formation enabling cancer tumors to grow. The company said its compound blocks the interaction of the growth factors with glyceptors on the surface of blood vessel cells. The binding of the growth factors to the glyceptors is thought to be among the early molecular events in triggering angiogenesis.