The U.S. Food and Drug Administration on Thursday approved prescription sales of aerosol pentamidine, a medication to prevent Pneumocystis carinii pneumonia, the most common life-threatening infection seen in AIDS patients.
The medication is already widely used by AIDS patients under a expanded distribution scheme announced by the FDA in February, and final marketing approval had been expected.
But the federal action ensures that almost all health insurers will now cover the expensive monthly treatments. Previously, many insurers, including the federal Medicare program, had refused to do so.
Dr. Louis W. Sullivan, U.S. Health and Human Services secretary, hailed the approval as a key step that may help "an estimated 100,000 or more individuals" who are at risk of developing the pneumonia.
"It should improve the quality of life for those at highest risk from this infection," he said in a prepared statement.
News of the FDA action was greeted with elation at San Francisco General Hospital, where much of the key data leading to aerosol pentamidine's approval was compiled.
"Super," said Dr. Paul A. Volberding, director of the hospital's division of AIDS activities.
Volberding said the announcement "shows that advances are being made" against AIDS and that the FDA "is listening to the pressure of the epidemic and the calls from the (patient) community for a more rapid response."
Dr. Fred R. Sattler, coordinator of the interdisciplinary AIDS Clinic at County-USC Medical Center in Los Angeles, said aerosol pentamidine "was the best studied form of pneumocystis prophylaxis that we have right now."
Sattler said effective use of aerosol pentamidine and other medications, such as trimethoprim-sulfamethoxazole, may "reduce the incidence of pneumocystis five- to 10-fold." But he cautioned that aerosol pentamidine was "far from perfect" and would need to be improved upon.
The medications work by preventing the pneumocystis germ from multiplying in the lungs and creating a serious infection.
Aerosol pentamidine is manufactured by LyphoMed Inc. of Rosemont, Ill. According to the FDA, the drug is recommended for AIDS patients who have had at least one episode of pneumocystis pneumonia, as well as individuals who have never had pneumocystis but are infected with the human immunodeficiency virus and have T-4 lymphocyte counts of 200 per cubic millimeter or less.
The drug is inhaled into the lungs as an aerosol spray. The FDA said it should be administered once every four weeks, using an inexpensive inhalation device known as the Respirgard II nebulizer, which is manufactured by Marquest Corp. of Englewood, Colo.
The cost of aerosol pentamidine to pharmacies is $99.45 per 300 milligram dose, but the drug's manufacturer estimates that one year of treatment might cost patients more than $2,000.
Also on Thursday, the U.S. Centers for Disease Control published recommendations for greatly expanded voluntary AIDS antibody testing in the Morbidity and Mortality Weekly Report. The primary goal of this expanded testing is to identify individuals who may benefit from treatments to prevent pneumocystis.
Aerosol pentamidine is the first new drug to be approved based on a clinical trial conducted largely by a group of practicing physicians. The group is the San Francisco Community Consortium.