MERCK AIDS INHIBITOR PROJECT: HIV-1 PROTEASE MAP

MERCK AIDS INHIBITOR PROJECT: HIV-1 PROTEASE MAP published in Feb. 16 issue of Nature sheds light on the angle and status of Merck's AIDS therapeutic work. Merck Chairman Roy Vagelos has previously called the development project an "enormous effort . . . historically one of the biggest" at Merck. However, the effort has had low visibility outside the scientific community prior to the Nature article. The report was authored by Manuel Navia et al., a group of nine Merck molecular biologists and biophysical chemists. The Feb. 16 article illustrates the crystal structure of protease molecule. The article maintains that "large regions of dimer, including the active site" are similar to other microbial aspartyl proteases. Merck emphasizes that no protease inhibitor has yet been found. However, a previous Merck research group publication in July of last year indicated the deactivating effect of a change in one amino acid at the active site. In a statement on the publication, the company says that "Merck researchers are working very hard to discover and develop an HIV-1 protease inhibitor." Merck explains that "as long as the proteins remain linked, they are not functional." The proteins must be separated, or cleaved apart, before new virus particles can be assembled." Merck research is now focusing on developing an agent that would lock into protease and block the enzyme from clipping the polyproteins. In November, Vagelos characterized the work of the AIDS group as "a great job; they couldn't be going faster." The Nature publication adds further luster to the Merck mystique and could pay its most long-term benefits to the company as a lure for more research talent. The firm is making the protease enzyme configuration available to the research community through the Brookhaven Protein Databank, run by Brookhaven National Labs in Upton, Long Island. Prior to the Nature article, Merck had published four previous scientific papers on the project: describing chemical synthesis of HIV-1 protease (Proceedings of the National Academy of Sciences 7129-7133, 1988); expression and purification (Journal of Biological Chemistry 2307-2312, 1989); the deactivating effect of a change in one amino acid (Proceedings of the National Academy of Sciences, July, 1988); crystallization of HIV-1 protease (Journal of Biological Chemistry 1919-1921, 1989). The head of the molecular biology group that expressed and purified the protease was Irving Sigal, the Merck researcher who was killed in the Pan Am jet crash over Scotland on Dec. 21.(ITEM 200)#050928M001J59307# #970804M001XFCWP5# (ITEM 201)(COPYRIGHT) 1989 F-D-C Reports, Inc., The Pink Sheet, February 20, 1989