Amgen's bid to expand the label on its hyperparathyroidism drug Sensipar has been hit by disappointing late-stage data from a kidney disease trial.

The US biotech has announced top-line results from a Phase III trial, called Evolve, which evaluated Sensipar/Mimpara (cinacalcet) for the reduction of the risk of mortality and cardiovascular events. The study involved 3,883 patients with secondary hyperparathyroidism (HPT) and chronic kidney disease receiving dialysis.

Although patients in the Sensipar arm experienced numerically fewer composite primary events (ie a reduction in all-cause mortality or first non-fatal cardiovascular event, including myocardial infarction, hospitalisation for unstable angina, heart failure), the results were not statistically significant. Detailed analyses from the landmark study are ongoing and will be presented at a major medical meeting later this year.

Sensipar, an oral calcimimetic agent, was approved in 2004 to treat secondary HPT in patients with CKD receiving dialysis. It is a big earner for Amgen and sales topped $808 million last year.