Industry has long questioned the feasibility of drugs mass-produced by transgenic animals, but recent first-time approvals by the European Commission and the US Food and Drug Administration suggest concerns are subsiding. The first transgenic drug approved in Europe, ATryn, is recombinant human antithrombin, an anticlotting protein secreted into the milk of transgenic goats developed by GTC Biotherapeutics in Framingham, Mass.
Biotechnology analyst Philip Nadeau at Cowen and Company in New York says ATryn's approval "removes any lingering concerns that proteins manufactured like this simply aren't approvable." Biotechnology most often employs cultured mammalian cells to generate protein drugs. The capital costs for a mammalian cell fermentation system that generates 100 kilograms of drug a year would run from $300 to $500 million, explains GTC, but 150 of GTC's goats can produce roughly the same amount of drug at one-tenth the cost. Meanwhile the FDA granted fast-track designation for rhC1INH from Pharming...