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FDA issued a warning to not prescribe the antibiotic, azithromycin, to patients for long-term prophylactic use post stem cell transplant due to a potential increased risk of cancer relapse and death. Patients with a history of donor stem cell transplant are at an increased risk of developing bronchiolitis obliterans syndrome. Bronchiolitis obliterans is an inflammatory lung condition. A recent clinical trial evaluated the use of azithromycin to prevent bronchiolitis obliterans syndrome. The trial, ALLOZITHRO, was discontinued after observing an increase in cancer relapse rates and death in patients treated with prophylactic azithromycin compared with patients receiving placebo. FDA is evaluating additional data and will provide further recommendations and guidance when their review is complete. Pfizer, the manufacturer of Zmax and Zithromax, the brand names for azithromycin, has issued a Dear Healthcare Provider Letter to professionals that treat donor stem cell transplant recipients.
Azithromycin has been used for a variety of infections including lung, sinus, skin, and others for many years. It is not labeled for the prevention of bronchiolitis obliterans syndrome. Donor stem cell transplant recipients who are currently taking azithromycin for the prevention of bronchiolitis obliterans should talk to their health care provider before stopping the medication. FDA urges health care providers and patients to report adverse effects related to azithromycin to the FDA MedWatch Program.
More information can be found in the following links:
- FDA Drug Safety Communication August 3, 2018
www.fda.gov/Drugs/DrugSafety/ucm614085.htm - Pfizer Dear Healthcare Professional Letter August 2018
www.fda.gov/downloads/Drugs/DrugSafety/UCM615362.pdf