Animal & Veterinary
FDA Approves First GE Animal, Human Health Product
by Jon F. Scheid, Editor
FDA Veterinarian Newsletter 2008 Volume XXIII, No V
The Food and Drug Administration announced in February that it had approved the first human health product, a biologic, made from a genetically engineered (GE) animal, and the first recombinant DNA (rDNA) construct in a GE animal.
The human health product is ATryn, an anticoagulant used for the prevention of blood clots in patients with a rare disease known as hereditary antithrombin (AT) deficiency.
ATryn is a therapeutic protein derived from the milk of GE goats. The goats have been genetically engineered by the introduction of an rDNA construct with instructions for the goats to produce human antithrombin in their milk. Antithrombin is a protein that naturally occurs in healthy individuals and helps to keep blood from clotting in the veins and arteries.
ATryn is manufactured by GTC Biotherapeutics, Inc., Framingham, MA.
FDA finalized a Guidance for Industry about GE animals just the month before. The guidance, titled “Regulation of Genetically Engineered Animals Containing Heritable Recombinant DNA Constructs,” explains FDA’s current thinking about how it will regulate GE animals.
FDA’s regulation of GE animals will require no new rules or laws. According to the guidance, FDA is regulating the rDNA constructs in GE animals under the new animal drug provisions of the Federal Food, Drug, and Cosmetic Act. One of the definitions of a new animal drug under the Act is “an article (other than food) intended to affect the structure or any function of the body of man or other animals….” According to that definition, an rDNA construct intended to affect the structure or function of an animal meets the definition of a new animal drug, regardless of the intended use of the resulting GE animals.
The guidance strongly encourages sponsors to consult with FDA early in their development of the GE animals to determine how best to develop the data and information needed for the Center for Veterinary Medicine to review in applications, as well as to clarify sponsor responsibilities for the shipping and labeling of investigational GE animals carrying rDNA constructs, animal disposition, record keeping, and other considerations in the regulatory approval process.
For GE animals producing substances to be used in or as drugs, biologics, or devices for use in humans, the appropriate Center within FDA reviews the human health product. In all cases, CVM reviews the rDNA constructs in GE animals.
FDA’s Center for Biologics Evaluation and Research (CBER) approved the human biologic based on the product’s safety and efficacy. During the approval process, CVM reviewed the recombinant DNA construct in the goats that produces ATryn to determine the safety of the construct to the animals and its stability in the genome of the goats over seven generations. CVM found no adverse outcomes.
Also, CVM reviewed and concurred with the sponsor’s plan to continue to monitor the construct and its expression for the lifetime of the approved product.
The Agency held an advisory committee meeting in January to seek the opinion about the biologic from outside experts, who agreed that ATryn is safe and effective. CVM also briefed the committee about the animal drug components of the application.