Keryx Biopharmaceuticals Inc said its sole drug in development, Zerenex, proved to be effective in treating patients with chronic kidney disease who were not on dialysis.
Keryx shares jumped 20 percent after the company said Zerenex met the main goal of a mid-stage trial.
Keryx said the pill had the potential to treat chronic kidney disease (CKD) patients, who have iron deficiency anemia. The standard treatment uses intravenous iron and erythropoiesis-stimulating agents, which stimulate red blood cell production.
Zerenex also increased the percentage of iron available in the body to make red blood cells, Keryx said.
The trial tested the drug in patients with chronic kidney disease who had iron deficiency anemia and elevated levels of serum phosphorus.
Zerenex was safe and well-tolerated, Keryx said. Serious adverse events occurred in six patients taking the drug, compared to 10 taking the placebo.
Keryx said that 19 percent of patients taking Zerenex discontinued treatment, compared to 32 patients taking the placebo.
The company said in January that Zerenex met the main goal of a late-stage study, reducing phosphate levels in the blood of patients with end-stage renal disease on dialysis.
The FDA is expected to review the drug to treat that condition on June 7 next year.
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