FDA Issues Warning About Long-Term Use of Azithromycin After Donor Stem Cell Transplant
Posted: Thursday, August 9, 2018
On August 3, the U.S. Food and Drug Administration (FDA) issued a warning that the antibiotic azithromycin should not be given long term to prevent bronchiolitis obliterans syndrome in patients with hematologic cancers who undergo donor stem cell transplantation. The results of the ALLOZITHRO clinical trial found an increased rate of relapse in cancers affecting the blood and lymph nodes, including death, in these patients. Once the FDA has completed its review of additional data, it will communicate its conclusions and recommendations.
The ALLOZITHRO trial was stopped approximately 13 months after the study completed enrollment of 480 patients because of an unexpected increase in the rate of both cancer relapses and death observed in patients taking azithromycin. Cancer relapse was observed in 77 patients (32.9%) with azithromycin treatment compared with 48 patients (20.8%) given placebo. A total of 95 patients died in the azithromycin treatment group versus 66 patients in the placebo group, making the 2-year survival rate 56.6% in the azithromycin arm compared with 70.1% in the placebo arm.
In the first few months of the trial, the death rate was about equal between those receiving azithromycin and placebo. However, an imbalance occurred subsequently and continued until the 2-year time point, when the study was stopped.
