European regulators have approved Amgen's Parsabiv for secondary hyperparathyroidism (sHPT), giving patients the potential to access the first new option to treat the disease in more than a decade.

sHPT is a common, serious and often progressive condition among patients with chronic kidney disease CKD, that develops in response to declining kidney function, when the parathyroid (PTH) glands increase the production of thyroid to maintain normal levels of calcium and phosphorus.

However, eventually this excess production is not enough to maintain normal levels, and at the point of CKD dialysis, this manifests as abnormal amounts of PTH, calcium and phosphorus that, in turn, can lead to significant clinical consequences, such as weakness and thinning of the bones.

Parsabiv (etelcalcetide) is a novel calcimimetic agent that suppresses the secretion of PTH by binding to and activating the calcium-sensing receptor on the parathyroid gland. The treatment is the first calcimimetic agent that can be given intravenously three times per week at the end of each dialysis session.

The submission is based on data from three Phase III studies, one of which showed that 74 percent of patients given the drug experienced a greater than 30 percent reduction from baseline in PTH compared with 8.3 percent in the placebo arm.

Parsabiv was also better than Amgen's older sHPT drug Sensipar (cinacalcet) for the secondary endpoints of proportion of patients achieving greater than 30 percent and greater than 50 percent reduction in mean PTH during the Efficacy Assessment Phase (EAP) compared with baseline, the firm noted.

"Keeping relevant lab values in recommended target ranges is an important part of managing sHPT, a chronic and complex disease with an already complicated medication regimen for many patients," said John Cunningham, professor of nephrology at University College London Medical School. "Treatment failures are quite common and Parsabiv provides a new tool that should give physicians more confidence that patients are getting the medication they need to treat their sHPT."

Sean E Harper, executive vice president of Research and Development at Amgen, also noted that, if poorly controlled, the condition can have significant clinical consequences. "With Parsabiv, we can put the delivery of the therapy in the hands of the healthcare provider and help ensure that these patients receive this important treatment as part of their dialysis session three times a week."

US regulators rejected the drug back in August via a Complete Response Letter, the details of which were not revealed.