Gilead Acquires Ouro Medicines for Up to $2.18 Billion to Advance T Cell Engager Autoimmune Therapies on March 24, 2026 acquisition Autoimmune Diseases bis(3-bis(4-chlorophenyl)methyl-4-dimethylaminophenyl)amine Galapagos gamgertamig Gilead Sciences OM336 Ouro Medicines T-cell engager +