Top-Line Results Announced for Osteoporosis Treatment

Amgen recently revealed positive results from a phase 3 study evaluating the safety and efficacy of Prolia (denosumab) compared with risedronate in patients receiving glucorticoids.

Glucorticoid-induced osteoporosis is a common form of secondary osteoporosis caused by glucorticoid therapies that treat inflammatory diseases. Fracture risk among patients receiving glucorticoids increases up to 75% within the first 3 months of treatment initiation.

Alternative treatments used for osteoporosis, such as bisphosphonates, have been shown to increase the risk of delayed fracture healing, which could be concerning for patients. Investigators in the current study found that patients taking Prolia had greater gains in bone mineral density at the lumbar spine and total hip, compared with patients taking risedronate, according to a press release.

Included in the phase 3 study were 795 patients randomized to receive Prolia 60-mg subcutaneously every 6 months, or oral risedronate 5-mg daily. There were 505 patients receiving continuing glucorticoid therapy, and 290 patients newly initiating the treatment, according to Amgen.

The primary endpoint was the change in lumbar spine bone mineral density at 12 months, and the secondary endpoints included the change in lumbar spine and total hip bone mineral density. All endpoints were met.

Findings from the study show that Prolia led to increased gains in bone mineral density in patients receiving continuing glucorticoid therapy compared with risedronate in the lumbar spine (4.4% versus 2.3%) and total hip (2.1% versus 0.6%).

In patients newly initiating glucorticoid therapy, Prolia also led to increased bone mineral density gains compared with risedronate at the lumbar spine (3.8% versus 0.8%) and total hip (1.7% versus 0.2%), according to Amgen. The most common adverse reactions in postmenopausal women are back pain, pain in extremities, musculoskeletal pain, hypercholesterolemia, and cystitis.

In men, common adverse reactions include back pain, arthralgia, and nasopharyngitis. Prolia specifically targets the RANK Ligand that is a regulator of osteoclasts, and is currently approved in over 80 countries.

The drug is currently approved in the United States and the European Union for multiple indications.

“The impact of glucocorticoid therapy on bone strength is frequently underestimated, and often leads to increased bone loss and ultimately, a fracture,” said Sean E. Harper, MD, executive vice president of Research and Development at Amgen. "We are excited that these data support the potential for Prolia use in patients with glucocorticoid-induced osteoporosis, the most common drug-induced form of the disease.”