Repligen Corp. on Wednesday said it has completed anagreement to reacquire certain rights to HIV monoclonalantibodies from Merck & Co. Inc.

Last October, Repligen dissolved its joint research program withMerck on a post-infective agent. Under terms of the agreementannounced Wednesday, Repligen has granted Merck a non-exclusive license under certain Repligen patent applications forHIV monoclonal antibodies that were developed jointly withMerck. In return, Merck will pay Repligen a royalty if itrequires a license to manufacture or sell a future Merckproduct.

The agreement does not affect the companies' AIDS vaccineresearch project, which has been renewed for a fifth year,through May 1993, said Ramesh Ratan, Repligen's chieffinancial officer.

Repligen (NASDAQ:RGEN) is now developing monoclonalantibodies as anti-infectives in mother-neonate transmission ofAIDS and as potential therapeutics for HIV, said Ratan. "Weexpect to file an investigational new drug application in late1992 or early 1993," he told BioWorld.

Merck has signed an agreement with MedImmune Inc.(NASDAQ:MEDI) to jointly develop and market monoclonalantibodies as post-exposure prophylactics against the AIDSvirus.

Repligen shares picked up 25 cents to $19.25. MedImmunegained $2.50 to $34.25. -- Kris Herbst

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