Adding azithromycin to malaria chemoprevention did not reduce incidence of death or hospitalization among African children compared with placebo, a randomized trial found.
In an intent-to-treat analysis, there were 250 deaths or hospital admissions among the azithromycin group versus 238 in the placebo group (IRR 1.1, 95% CI 0.88-1.3), reported Daniel Chandramohan, PhD, of the London School of Hygiene and Tropical Medicine, and colleagues.
However, those in the azithromycin group had less frequent rates of gastrointestinal infections, upper respiratory tract infections, and non-malarial febrile illnesses, the authors wrote in the New England Journal of Medicine
These findings were also presented at the World Health Organization executive board meeting currently being held in Geneva.
Mass administration of azithromycin has helped with trachoma control, the authors said, as well as reductions in skin, GI, and upper respiratory infection. But they noted the “surprising” results of a trial in Ethiopia that found a 49% reduction in all-cause mortality among young children the year after mass administration of the drug.
Chandramohan’s group enrolled children, ages 3 to 59 months, in Burkina Faso and Mali to receive sulfadoxine-pyrimethamine plus amodiaquine during peak malaria transmission season, and were assigned to receive 100 mg azithromycin or matching placebo. These combinations were administered in four 3-day cycles, at monthly intervals for three successive malaria transmission seasons, the authors said.
The study’s primary endpoint was death or hospital admission for ≥24 hours that was not due to trauma or elective surgery during the intervention period.
Overall, 19,578 children were randomized — 9,735 to the azithromycin group and 9,843 to the control group. Children would exit the trial when they reached age 5 years, the authors said, and new children were enrolled. At the last follow-up visit, there were 10,885 children in the azithromycin group and 10,852 in the control group.
While there was no reduction in deaths or hospitalizations in the azithromycin group versus placebo, the authors found evidence of an interaction between trial group and trial site. They noted that the incidence of the primary endpoint was higher in the azithromycin group in Burkina Faso (IRR 1.3, 95% CI 1.0-1.7) but not in Mali (IRR 0.84, 95% CI 0.64-1.1). But they added that “no plausible mechanism to explain this difference was found, and given the borderline increased incidence in Burkina Faso, it may be a chance finding.”
When examining clinic visits for certain events, the azithromycin group had a lower incidence than the placebo group of the following:
- GI infections: IRR 0.85 (95% CI 0.79-0.91)
- Upper respiratory tract infections: IRR 0.85 (95% CI 0.81-0.90)
- Non-malarial fevers: IRR 0.79 (95% CI 0.73-0.87)
Moreover, an exploratory analysis found that incidence of skin diseases, especially those with a bacterial cause, was lower in the azithromycin group, the authors said, which was “consistent with findings of previous studies in which azithromycin was used in trachoma control programs.” They also found the prevalence of malaria parasitemia was similar between the two groups.
There were no severe adverse events related to the trial drugs, and diarrhea was the most frequent adverse event. Incidence of adverse events were similar between groups, the authors noted.
Study limitations included the fact that randomization was performed according to household versus village, which reduced the potential for bias, but precluded the potential for a herd effect. The authors also cited “limited safety data” because both seasonal malaria chemoprevention and mass administration of azithromycin “have now been given to millions of children with no major safety concerns.”
This study was supported by grants from the Joint Global Health Trials scheme, including the U.K. Medical Research Council (UKMRC), the Department for International Development, the National Institute for Health Research, and the Wellcome Trust.
Chandramohan disclosed no relevant relationships with industry. C-authors disclosed grants from UKMRC.