STOCK PURCHASE AGREEMENT This STOCK PURCHASE AGREEMENT is dated as of the 27th day of October, 1999 by and among Transkaryotic Therapies, Inc., a Delaware corporation with its principal office at 195 Albany Street, Cambridge, MA 02139 (the "COMPANY"),...Stock Purchase Agreement • March 24th, 2000 • Transkaryotic Therapies Inc • Biological products, (no disgnostic substances) • Massachusetts
