The US Food and Drug Administration (FDA) has approved Vifor Pharma's hyperphosphatemia drug Velphoro for the control of serum phosphorus levels in patients with chronic kidney disease (CKD) on dialysis.

Approval of Velphor, an iron-based, calcium-free, chewable phosphate binder, was based on Phase III study, which met its primary and secondary endpoints.

The open-label, randomised, active controlled, parallel group Phase III trial was designed to assess the safety and efficacy of Velphoro compared to sevelamer carbonate, followed by a randomised comparison of Velphoro maintenance dose versus Velphoro inactive low-dose in dialysis patients with hyperphosphatemia.

Results from the trial showed that Velphoro controls hyperphosphatemia with fewer pills than sevelamer carbonate, the current standard of care in patients with CKD on dialysis, and the average daily dose to control hyperphosphatemia was 3.3 pills per day after 52 weeks.

Fresenius Medical Care North America will be responsible for marketing the hyperphosphatemia drug in the US from 2014.

The active ingredient of Velphoro (previously known as PA21) is produced by Vifor Pharma in Switzerland.

Hyperphosphatemia, an abnormal elevation of phosphorus levels in the blood, is a common and serious condition in CKD patients on dialysis, with most patients treated with phosphate binders.

The company said that despite the availability of several different phosphate binders, 50% of patients are still unable to achieve and maintain their target serum phosphorus levels.

In some patients, non-compliance due to the high pill burden and poor tolerability seems to be major factor in the lack of control of serum phosphorus levels.

On an average, dialysis patients daily take about 19 pills per day with phosphate binders including about 50% of the total daily pill burden.

Currently, regulatory processes for Velphoro in Europe, Switzerland and Singapore are being carried out and decisions are expected in the first half 2014, while further submissions for approval are being prepared.