FDA issues a Complete Response Letter for Human Genome Sciences' raxibacumab BLA

Human Genome Sciences, Inc. (Nasdaq: HGSI) today announced that it has received a Complete Response Letter from the U.S. Food and Drug Administration (FDA) relating to the Company’s Biologics License Application (BLA) requesting the approval of raxibacumab for use in the treatment of inhalational anthrax. The FDA issues Complete Response Letters to request additional information needed to complete the review of a BLA.

“We have responded to all of FDA’s previous questions. We plan to address the current questions as well,” said Sally D. Bolmer, Ph.D., R.A.C, Senior Vice President, Development and Regulatory Affairs, HGS. “In certain respects, the Complete Response Letter appears to be inconsistent with the FDA’s published final rule governing the development of new drugs when human efficacy studies are not ethical or feasible.”

James H. Davis, Ph.D., J.D., Executive Vice President and General Counsel, HGS, and leader of the Company’s raxibacumab program with the U.S. Government, said, “It is unfortunate that it was not possible to resolve these questions before the PDUFA date passed. However, HGS has delivered 20,000 doses of raxibacumab to the U.S. Strategic National Stockpile under our contract with BARDA, so it is currently available in the Stockpile for use in the event of an emergency while we complete our discussions with the FDA.”

Raxibacumab represents a new way to address the anthrax threat. While antibiotics can kill the anthrax bacteria, they are not effective against the deadly toxins that the bacteria produce. Raxibacumab targets anthrax toxins after they are released by the bacteria into the blood and tissues. In an inhalation anthrax attack, people may not know they are infected with anthrax until the toxins already are circulating in their blood, and it may be too late for antibiotics alone to be effective.

The July 9 edition of The New England Journal of Medicine published the results of two pivotal randomized placebo-controlled studies conducted in rabbits and monkeys to evaluate the efficacy of raxibacumab, as well as the results of human safety studies, which supported the use of raxibacumab in the event of life-threatening inhalation anthrax disease.

Raxibacumab is a first-in-class treatment for anthrax, and the first procurement under Project BioShield of a product discovered and developed after the September 11, 2001 terrorist attacks. Raxibacumab is being developed under a contract entered into in 2006 with the Biomedical Advanced Research and Development Authority (BARDA) of the Office of the Assistant Secretary for Preparedness and Response (ASPR), U.S. Department of Health and Human Services (HHS).

SOURCE Human Genome Sciences