FDA Advisers Reject Second Biotech Drug
The biotechnology industry Tuesday received its second lukewarm signal in two days from a key government advisory panel when the group backed only one of two genetically engineered drugs.
The Food and Drug Administration’s nine-member Biological Response Modifiers Advisory Committee, meeting in Rockville, Md., failed to recommend approval of a substance called granulocyte macrophage colony stimulating factor, or GM-CSF, for bone marrow transplant patients.
The committee said Immunex Corp. of Seattle presented insufficient evidence about which patients would most likely benefit from the drug. It recommended that GM-CSF be made available to patients only on an experimental basis.
The panel did, however, unanimously recommend that Schering-Plough Corp. of Madison, N.J., be allowed to sell a drug called interferon alpha 2b to treat a chronic form of hepatitis.
The drugs were among four agents produced through genetic engineering techniques that the panel considered over two days. On Monday, the panel endorsed one drug for a rare blood disease but failed to recommend a second for kidney cancer.
Although any drug must receive final FDA approval, the hearings are important for the biotechnology industry because the FDA generally follows the panel’s advice and positive recommendations indicate to investors that years of costly research will likely reap returns.
Approval of all four drugs “would have been a big, positive step for the industry,” said Pamela Bridgen, executive director of the Assn. of Biotechnology Companies in Washington. “It’s not as good as it might have been.”
The biotechnology industry has grown around recently developed techniques known as recombinant DNA technology, which involves manipulating genes--the blueprints for all life.
The techniques are used to produce drugs by inserting a gene for a substance that occurs naturally in the human body in tiny amounts into another organism, usually bacteria, to produce a substance or a close substitute in amounts large enough to treat a disease.
GM-CSF is a protein that encourages certain white blood cells to grow. Researchers hoped it could be used to improve the success of transplanted bone marrow, which produces white blood cells.
Although the committee did not support full approval, the panel recommended that Immunex make the drug available to all eligible patients on an experimental basis, said FDA spokeswoman Faye Peterson.
Interferon alpha 2b, another protein, has already been approved to treat venereal warts, hairy cell leukemia and Kaposi’s sarcoma, a form of cancer common among AIDS patients.
The committee Monday endorsed a drug made by Genentech Inc. of South San Francisco, Calif., called interferon gamma. It is used to treat a rare inherited white blood cell disorder called chronic granulomatous disease.
