Hypocalcemia risk comparable between denosumab, oral bisphosphonate

Incidence rates of hypocalcemia in women with postmenopausal osteoporosis are comparable between those treated with denosumab or bisphosphonate monotherapy and the rate of hypocalcemia among those treated with denosumab is consistent with the labeled risk, study data show.

Leslie Spangler, PhD, of the Center for Observational Research at Amgen, and colleagues evaluated administrative data from U.S. Medicare (2010-2013) on 3,973,567 women (50% aged 75 years) with postmenopausal osteoporosis to report on incidence rates of events with expected early onsets including hypocalcemia, dermatologic events, hypersensitivity, serious infection and acute pancreatitis. Follow-up was a mean of 2.5 years.

Participants were categorized into three groups based on use of osteoporosis treatments during follow-up including denosumab (Prolia, Amgen) only, oral bisphosphonate only or IV bisphosphonate only.

Hypocalcemia was present in 217 participants in the denosumab and oral bisphosphonate groups combined; baseline chronic kidney disease was observed in 23% of those participants.

The denosumab group had the highest incidence of hypocalcemia (74 per 100,000 person-years). The IV bisphosphonate group had the highest incidences for serious infection (10,825 per 100,000) and hypersensitivity (307 per 100,000). Incidence rates for dermatologic events and acute pancreatitis were similar across the three groups.

The researchers noted that the estimated incidence rates “did not account for differential distribution of risk factors that may contribute to variation in [incidence rates] across exposure cohorts.” – by Amber Cox

Reference:

Spangler L, et al. Abstract MO0667. Presented at: American Society for Bone and Mineral Research Annual Meeting; Sept. 8-11, 2017; Denver.

Disclosure: Spangler reports she is an employee of Amgen.