Complex sentence: Nutley had been the U.S. headquarters of Hoffmann-La Roche and was the site of the creations of the medications Valium and Librium, later becoming one of the major R&D sites for Roche, hosting major research areas in oncology, virology and inflammation.
Split into simpler sentences: Nutley had been the US headquarters of Hoffmann-La Roche and was the site of the creations of the medications Valium and Librium. Now the Nutley site is one of the major R&D sites for Roche, hosting three major research areas-oncology, virology and inflammation.