Arthritis drugs must carry stern warnings
WASHINGTON - Arthritis and autoimmune drugs marketed by Amgen Inc., Wyeth, and Johnson & Johnson must carry stronger warnings about fungal infections tied to more than 45 deaths, US regulators said.
The new cautions, posted yesterday on the Food and Drug Administration's website, also apply to Abbott Laboratories' Humira and UCB SA's Cimzia. Market-leading Enbrel, sold by Amgen and Wyeth, J&J's Remicade, and Humira were among the 25 biggest drugs worldwide last year, with $13.5 billion in combined sales, according to data compiled by Bloomberg. They are usually used to treat rheumatoid arthritis.
At least 241 patients have developed histoplasmosis, an infection caused by a fungus found in the Ohio and Mississippi river valleys, in the decade since the first drugs were approved, the FDA said. Forty-five died, including 12 whose doctors didn't recognize the infection and delayed treatment, the agency said. More deaths were reported from other fungal infections, though the FDA wouldn't say how many.
"These infections need to be identified early enough so treatment is not delayed," said Jeffrey Siegel, a clinical team leader in the FDA's division of anesthesia, analgesia, and rheumatology products.
The FDA ordered the companies to strengthen existing cautions in a black box in the drugs' prescribing information, the agency's strictest form of caution. They also must educate doctors about the risks and the symptoms of fungal infections. The drug makers all said in separate statements that they are working with the agency to make the changes.
The new warnings won't hurt demand, because the risks were already known, said analyst Alex To, who covers California-based Amgen for Natixis Bleichroeder.
The medicines are approved to treat a variety of conditions, including rheumatoid arthritis, juvenile idiopathic arthritis, psoriasis, and Crohn's disease. They work by blocking the inflammatory protein called tumor necrosis factor-alpha, or TNF-alpha. This "is a double-edged sword," Siegel said, since suppressing the immune system also leaves patients at risk for infections. 