Vifor Pharma has completed its submissions in the major markets for PA21 by filing the new phosphate binder with Swiss regulators.

The firm says the filing for PA21 (iron(III)-oxyhydroxide) to the Swiss Agency for Therapeutic Products (Swissmedic) for treating hyperphosphatemia in patients with chronic kidney disease, follows the recent submission of a New Drug Application in the USA. The file has also been accepted for review by the European Medicines Agency and regulators in Singapore.

The filings for PA21 are based on Phase III data which demonstrated that the chewable pill successfully controls hyperphosphatemia, ie the accumulation of phosphorus in the blood, in patients with CKD on dialysis. Vifor, the pharmaceutical unit of Galenica, noted that a six-month extension of the study has also been completed recently and preliminary results show that the safety and efficacy of PA21 are maintained with the advantage of a low pill burden.

Three-four pills compared to nine

Rudolf Wuthrich of the University of Zurich and an investigator in the PA21 development programme, said management of hyperphosphatemia in dialysis patients "remains a challenge due to insufficient patient adherence" as sufferers have to take on average nine pills of phosphate binders daily. "It is a lot, considering the significant amount of additional tablets taken by dialysis patients every day", he claimed, noting that patients would only require three-four pills per day with PA21. This should lead to "better acceptance of treatment by dialysis patients and help nephrologists to optimise serum phosphate control in patients with end stage renal disease", he concluded.

In 2011, all rights to PA21 were transferred to a new venture, Vifor Fresenius Medical Care Renal Pharma, and analysts believew the firm could be oto a winner, given that trials have shown it is as effective as a current standard of therapy, Sanofi's Renvela (sevelamer carbonate), but also comes with a much lower pill burden. PA21 is in Phase II clinical in Japan where it is being developed by Kissei Pharmaceuticals Co.