Drug Manufacturing in Bioengineered Goats: FDA Says It Looks Safe
Would you take a drug made from the milk of a genetically modified goat? A committee of expert advisers to the FDA will take a swing at that question, weighing the safety and effectiveness of such a treatment on Friday. The U.S. drug regulator is seeking advice on whether to approve an application from Framingham, MA-based GTC Biotherapeutics, a company aiming to prove that the drug it makes in goats, an anti-clotting agent, should be the first transgenic- animal-derived drug cleared for sale in the U.S.
Given the ultra-cautious tone the FDA is often accused by companies of taking toward new medicines, GTC’s recombinant antithrombin, a protein drug marketed as ATryn in Europe, sounds like a non-starter here, right? Nope. “The safety profile appears to be acceptable,” FDA staff said, and “ATryn at the recommended dose is effective” in patients with a hereditary deficiency of the anti-clotting protein, according to briefing materials posted online this morning, in preparation for Friday’s meeting of the Blood Products Advisory Committee in Rockville, MD.
Driving home these points in a persuasive way to the advisory panel will be critical for GTC (NASDAQ: GTCB) as a company. It is holding on by the thinnest of threads, with its stock closing yesterday at 57 cents. ATryn, approved in Europe in 2006, is sold there for a rare hereditary disorder that causes clotting. But the drug hasn’t generated nearly enough sales to sustain GTC, so its hopes are riding on U.S. approval. If GTC can get this drug through the FDA, it would also clear the path for other companies that hope to use transgenic farm animals as drug factories, a process sometimes referred to as “pharming.” (In fact Pharming is the name of one such company, a Dutch firm.)
So why on earth would anybody want to make drugs this way? Don’t scientists already know how to make genetically engineered protein drugs through fermentation-style techniques using standard lab organisms like E. coli, yeast, or hamster cells?
As David Stipp described it for us in a feature back in February, pharming’s appeal comes from its ability to churn out large quantities of protein drugs in a cheap way. And GTC makes the point that all protein drugs have to go through a rigorous purification process to separate the drug from all the gunk it brews with. As long as GTC can prove its end product is pure and consistent, who cares if it came from a goat udder?
We’ll see if the FDA panel agrees when it hands down a recommendation on Friday afternoon. The FDA isn’t required to follow the recommendations of its panels, although it usually does. The agency’s deadline for deciding whether or not to apporve the GTC drug is Feb. 7.