Serious Infection Risk Not Significantly Higher With Denosumab vs Alendronate in Osteoporosis

Denosumab (DEN) vs alendronate (ALN) is not significantly associated with increased risk for serious infection, according to study results presented at the American Society for Bone and Mineral Research (ASBMR) Annual Meeting, held virtually from September 11 to 15, 2020.

Researchers extracted data from a 20% representative sample of Medicare beneficiaries between 2011 and 2017. Patients with osteoporosis aged ≥66 years who were initiated with DEN or ALN between 2012 and 2016 were eligible for inclusion in the study. Primary outcomes were hospitalization due to any serious infection, including cellulitis, infectious endocarditis, gastroenteritis, diverticulitis, labyrinthitis, osteomyelitis, urinary tract infection, and respiratory infection. Adjusted 2-year infection probabilities were calculated separately for DEN and ALN users. Probabilities were adjusted for patient demographic data, previous zoledronic acid use, and previous serious and mild infections. Analyses were also stratified by sex.

The study cohort included 73,750 patients receiving DEN and 103,790 patients receiving ALN. Mean follow-up time was 20.9 and 19.2 months for the DEN and ALN cohorts, respectively. Compared with patients receiving ALN, those receiving DEN had a higher mean age (78.1 vs 76.7 years, respectively), were a greater percentage of women (93.3% vs 89.7%, respectively), and were more often White (87.2% vs 80.5%, respectively).

Previous serious infection rates were comparable between groups, though patients receiving DEN vs ALN had a higher rate of previous mild infections (59.1% vs 53.9%, respectively). Overall, 5.9% and 4.9% of patients receiving DEN and ALN, respectively, experienced serious infections during follow-up. Adjusted 2-year infection probability was 6.8% (95% CI, 6.50%-7.05%) in the DEN group, compared to 6.3% (95% CI, 6.13%-6.55%) in the ALN group; however, the difference was not clinically significant. Adjusted probabilities for cause-specific serious infections varied but were also comparable between groups.

In real-world practice, serious infection risk was not significantly higher with DEN compared to ALN in osteoporosis. However, the small percentage of men in the study prevented accurate estimates for this cohort; results were better generalized to women.

Reference

Liu J, Guo H, Niewan K. Infection among denosumab and alendronate users for osteoporosis. Presented at: ASBMR 2020 Virtual Annual Meeting; September 11-15, 2020. Poster #P-637.

This article originally appeared on Rheumatology Advisor