The US Food and Drug Administration (FDA) has added a boxed warning to the label of the osteoporosis drug denosumab (Prolia) about increased risk for severe hypocalcemia in patients with advanced chronic kidney disease (CKD).
Denosumab is a monoclonal antibody, indicated for the treatment of postmenopausal women with osteoporosis who are at increased risk for fracture for whom other treatments aren’t effective or can’t be tolerated. It’s also indicated to increase bone mass in men with osteoporosis at high risk for fracture, treat glucocorticoid-induced osteoporosis in men and women at high risk for fracture, increase bone mass in men at high risk for fracture receiving androgen-deprivation therapy for nonmetastatic prostate cancer, and increase bone mass in women at high risk for fracture receiving adjuvant aromatase inhibitor therapy for breast cancer.
This new warning updates a November 2022 alert based on preliminary evidence for a “substantial risk” for hypocalcemia in patients with CKD on dialysis.
Upon further examination of the data from two trials including more than 500,000 denosumab-treated women with CKD, the FDA concluded that severe hypocalcemia appears to be more common in those with CKD who also have mineral and bone disorder (CKD-MBD). And, for patients with advanced CKD taking denosumab, “severe hypocalcemia resulted in serious harm, including hospitalization, life-threatening events, and death.”
Most of the severe hypocalcemia events occurred 2-10 weeks after denosumab injection, with the greatest risk during weeks 2-5.
The new warning advises healthcare professionals to assess patients’ kidney function before prescribing denosumab, and for those with advanced CKD, “consider the risk of severe hypocalcemia with Prolia in the context of other available treatments for osteoporosis.”
If the drug is still being considered for those patients for initial or continued use, calcium blood levels should be checked, and patients should be evaluated for CKD-MBD. Prior to prescribing denosumab in these patients, CKD-MBD should be properly managed, hypocalcemia corrected, and patients supplemented with calcium and activated vitamin D to decrease the risk for severe hypocalcemia and associated complications.
“Treatment with denosumab in patients with advanced CKD, including those on dialysis, and particularly patients with diagnosed CKD-MBD should involve a health care provider with expertise in the diagnosis and management of CKD-MBD,” the FDA advises.
Once denosumab is administered, close monitoring of blood calcium levels and prompt hypocalcemia management is essential to prevent complications including seizures or arrythmias. Patients should be advised to promptly report symptoms that could be consistent with hypocalcemia, including confusion, seizures, irregular heartbeat, fainting, muscle spasms or weakness, face twitching, tingling, or numbness anywhere in the body.
In 2022, an estimated 2.2 million Prolia prefilled syringes were sold by the manufacturer to US healthcare settings.
A version of this article appeared on Medscape.com.