* Amylin Pharmaceuticals Inc., of San Diego, lost 44 percent of its stock value in the first day of trading after it reported Johnson & Johnson (J&J), of New Brunswick, N.J., is pulling out of their collaboration to develop Amylin's lead product, pramlintide for diabetes. Pramlintide, a synthetic analogue of the human hormone amylin, is in Phase III trials. J&J's decision was made public late Monday. Amylin's stock (NASDAQ:AMLN) closed Tuesday at $2.813, down $2.25. (See BioWorld Today, March 3, 1998, p. 1.)

* ArQule Inc., of Medford, Mass., and Sepracor Inc., of Marlborough, Mass., entered a partnership to discover and develop therapeutics for resistant strains of HIV and hepatitis B. After using ArQule's Mapping Array program to identify lead compounds, the companies will use ArQule's Directed Array program to optimize them. The pair will share ownership rights to any active lead compounds, as well as revenues upon commercialization of them.

* Cellex Biosciences Inc., of Minneapolis, received notification from Unisyn Technologies Inc., of Hopkinton, Mass., that its board voted to terminate the merger agreement between the two companies. Unisyn claimed Cellex's financial performance and condition declined since the merger agreement began. Cellex denied the claim.

* Genentech Inc., of South San Francisco, signed an agreement with Dako A/S, of Copenhagen, Denmark, under which Dako will develop an in vitro diagnostics kit to be used for screening breast cancer patients for overexpression of the growth factor known as HER2. The test will show eligibility for treatment with Genentech's monoclonal antibody to HER2, Herceptin (trastuzumab), which currently is under development. Genentech will grant to Dako a license under Genentech's patent rights, and expertise for development of the immunohistochemical kit to be used in testing for overexpression of HER2. Dako will pay Genentech a royalty on worldwide sales of the kits.

* Idec Pharmaceuticals Corp., of San Diego, and SmithKline Beecham plc, of London, selected primatized IDEC-151 (Clenoliximab) as their lead anti-CD4 antibody for treating rheumatoid arthritis. Results from a Phase I trial testing safety, tolerance and clinical activity have been favorable, the companies said. Their agreement is worth up to $60 million to Idec, most of which already has been paid. Last year, they suspended a Phase III trial of another primatized monoclonal antibody. (See BioWorld Today, June 25, 1997, p. 1.)

* LXR Biotechnology Inc., of Richmond, Calif., entered a collaborative research agreement with Copernicus Gene Systems Inc., of Cleveland. The deal will focus on integrating a proprietary anticancer gene belonging to LXR with the enabling DNA compaction and expression technologies of Copernicus. LXR has discovered gene and gene families related to controlling apoptosis, or programmed cell death.

* Scriptgen Inc., of Medford, Mass., withdrew its initial public offering (IPO) of 3 million shares, citing unattractive market conditions. Scriptgen, of Medford, Mass., which received a patent early this year on its high-throughput screening process, called the Any Target Ligand Affinity Screen (ATLAS), a high-throughput pre-screening process, made public its plans for its IPO last November. (See BioWorld Today, Nov. 24, 1997, p. 1.)

* Quintiles Transnational Corp., of Research Triangle Park, N.C., acquired T2A SA, of Paris, a leading French contract sales organization serving the world's fourth-largest pharmaceutical market. Quintiles acquired T2A in exchange for Quintiles stock in a pool of interests transaction that is expected to be neutral to slightly accretive to Quintiles' earnings per share. Quintiles also completed the previously announced acquisition of More Biomedical Contract Research Organization Ltd., of Taiwan.