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. 2021 Mar;20(2):e16-e18.
doi: 10.1016/j.jcf.2020.11.005. Epub 2020 Nov 24.

Long-term azithromycin use is not associated with QT prolongation in children with cystic fibrosis

Amalia S Magaret  1 , Jack Salerno  2 , Jason F Deen  3 , Margaret Kloster  4 , Nicole Mayer-Hamblett  5 , Bonnie W Ramsey  2 , Dave P Nichols  2
Affiliations

Long-term azithromycin use is not associated with QT prolongation in children with cystic fibrosis

Amalia S Magaret et al. J Cyst Fibros. 2021 Mar.

Abstract

Chronic Azithromycin (AZM) is a common treatment for lung infection. Among adults at risk of cardiac events, AZM use has been associated with cardiovascular harm. We assessed cardiovascular safety of AZM among children with CF, as a secondary analysis of a placebo-controlled, clinical trial, in which study drug was taken thrice-weekly for a planned 18 months. Safety assessments using electrocardiogram (ECG) occurred at study enrollment, and then after 3 weeks and 18 months of participation. Among 221 study participants with a median of 18 months follow-up, increased corrected QT interval (QTc) of ≥30 msec was rare, at 3.4 occurrences per 100 person-years; and incidence of QTc prolongation was no higher in the AZM arm than the placebo arm (1.8 versus 5.4 per 100 person-years). No persons experienced QTc intervals above 500 msec. Long-term chronic AZM use was not associated with increased QT prolongation.

Keywords: Azithromycin; Cystic fibrosis; Pulmonary exacerbation; QT prolongation.

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Figures

Figure 1.
Figure 1.. QTc over time and by treatment taken
Lines show group-specific means by treatment taken at each visit. Because of the open-label drug phase, more participants are taking AZM during the later visits.
See this image and copyright information in PMC

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