* Alexion Pharmaceuticals Inc., of New Haven, Conn., filed an investigational new drug application with the FDA to begin clinical trials of 5G1.1, the company's C5 complement inhibitor, for treatment of rheumatoid arthritis. The drug is a monoclonal antibody designed to block complement activity and reduce inflammation associated with chronic autoimmune diseases.

* Bausch & Lomb Inc., of Rochester, N.Y., completed its acquisition of Chiron Vision, a division of Emeryville, Calif.-based Chiron Corp. The $300 million cash purchase was proposed in October 1997. (See BioWorld Today, Oct. 23, 1997, p. 1.)

* Diatide Inc., of Londonderry, N.H., said it completed enrollment of its pivotal Phase III trial of P829, which is an imaging agent for detection and localization of cancer in the lung. The company expects to submit a new drug application for the product with the FDA in the second quarter of 1998. Diatide described P829 as a small-molecule, synthetic peptide combined with technetium-99m. It is designed to bind to a somatostatin receptor present on several types of cancer cells. The company expects to use the product as an alternative to invasive procedures to detect cancer.

* NaPro BioTherapeutics Inc., of Boulder, Colo., and its partner Ivax Corp., of Miami, said the FDA granted tentative approval for Paxene, the company's paclitaxel drug, for Kaposi's sarcoma as a second-line therapy. Final marketing approval, however, may not follow until 2004, which is when New York-based Bristol-Myers Squibb Co.'s seven-year orphan drug status in a related indication expires for its paclitaxel product, Taxol. Ivax said it will pursue alternative strategies for getting Paxene on the market in the U.S. for Kaposi's sarcoma.

* Ribozyme Pharmaceuticals Inc., of Boulder, Colo., signed a letter of intent to collaborate with Warner-Lambert Co., of Morris Plains, N.J., on evaluation of specific disease-related genes for drug intervention using Ribozyme's target validation technology. Financial terms were not disclosed. Ribozyme will be working with Warner-Lambert's Parke-Davis division.