Affymax anemia drug shows promise in small study

By Bill Berkrot

NEW YORK, April 3 (Reuters) - An experimental anemia drug being developed by Affymax Inc (AFFY.O) and Takeda Pharmaceutical Co Ltd (4502.T) appears to be safe and effective in kidney dialysis patients, according to interim data from a small mid-stage trial presented on Thursday.

Hematide, a synthetic drug that would compete with biologic anemia medicines that have faced restrictions over safety and potential overuse concerns, successfully maintained hemoglobin levels in the target range of 11 to 12 grams per deciliter over 18 months of treatment in the ongoing study, researchers said.

None of the serious adverse events seen in the 81-patient study were believed to be associated with Hematide, Dr Robert Geronemus, who presented the data at the National Kidney Foundation Spring Clinical Meeting in Dallas, said in an interview.

"Dialysis patients are typically a sick group of people expected to have complications and hospitalizations," explained Geronemus. "For a study to have no serious adverse events felt to be drug-related in phase 2, that's encouraging."

All patients in the study were on the drug, so there was no comparison with placebo or other medicines. Larger, late-stage studies to be used to seek marketing approval will test Hematide against standard treatments, Geronemus said.

Hematide, which is being studied for use against anemia in both kidney dialysis and chemotherapy patients, is administered just once a month. That could be a major advantage over current standard treatments from Amgen Inc (AMGN.O) and Johnson & Johnson (JNJ.N), which are given with dialysis about three times a week.

Hematide, like current treatments, is an erythopoiesis stimulating agent, or ESA, that boosts red blood cells. But as a synthetic it could prove to be significantly less expensive to produce than the genetically engineered biotech ESAs.

All patients in the Hematide trial, which is expected to continue through four years of treatment, had previously been treated with Amgen's Epogen. Similar drugs include Amgen's Aranesp and J&J's Procrit.

Recently revised guidelines on the use of ESAs call for hemoglobin levels that do not exceed 12 grams.

In the Hematide study, patients at 18 months had a mean hemoglobin level of 11.3 grams, researchers said.

"It definitely works and maintains patients within that nice target range," Geronemus said.

"It's been remarkably stable throughout the 18 months," he said. "There's no reason to believe something is going to change between the 12th month and the 23rd month."

Geronemus said Hematide could become a very important drug if larger studies confirmed these early results.

"I'm cautiously optimistic," he said. "The study is very encouraging." (Editing by Gerald E. McCormick)