UK drugmaker Shire will be disappointed by news that its Fosrenol failed to meet the primary endpoint of a Phase II trial of reducing the amount of phosphate in pre-dialysis patients with stage 3 and 4 chronic kidney disease to normal levels.

However, it was not all bad news; the firm pointed out that more patients treated with Fosrenol (lanthanum carbonate) achieved this goal than those in the placebo arm, and the trial did meet its secondary goal of a statistically-significant cut in phosphate levels versus the control,indicating that the agent can effectively reduce serum phosphate levels in CKD patients not yet receiving dialysis.

First launched in 2005, Fosrenol is already available in 23countries worldwide for the reduction of phosphate levels in patients with end stage (stage 5) renal disease. While hyperphosphataemia is more common at this stage of the disease, the problem of can start before patients require dialysis.

The management of hyperphosphataemia – which occurs as the kidneys lose their ability to excrete phosphate – is crucial for patients with CKD, as excess levels can lead to serious health problems such as cardiovascular disease and brittle bones. In fact, research has shown that foreach mg/dL increase in mean serum phosphorus, the relative risk of death increases by 6%, the firm noted.

According to Shire, the findings of the Phase II trial add further credence to the recent recommendation of a US Food and Drug Administration Cardiovascular and Renal Drugs Advisory Committee to extend theuse of phosphate binders to include treatment of CKD stage 4 patients with hyperphosphataemia.

Label to follow recommendations

Ray Pratt, Vice President and Scientific Leader for Shire’s renal unit, told PharmaTimes UK News that, although the proportion of patients with stage 4 disease and high phosphate levels is not huge, the company is working with US regulators to extend Fosrenol’s label to fall in line with current recommendations for treatment.

He also confirmed that Shire is planning to conduct further studies in patients with CKD in the USA, although the design and duration of these has not yet been decided. Similarly, he said that the company is in discussions with regulatory agencies regarding expansion of the drug’s use in Europe, and that plans are underway to kick of studies in pre-dialysis patients in the region next year.