MDGN-201

Peginesatide, if approved, would be available only to patients on dialysis, who comprise 380,000 of the 26 million people in the US with chronic kidney disease.So, companies are working towards developing broader-reaching anemia therapies, too.One such strategy involves gene therapy.For example, the US-Israeli biopharmaceutical company Medgenics is advancing a cell-based erythropoietin gene therapy, called Epodure, for predialysis patients.The treatment involves harvesting a sliver of tissue from beneath a person′s skin, transducing it with an adenovirus engineered to express the gene encoding erythropoietin and then implanting the altered tissue back into participants several weeks later.In early clin. data presented in Nov. at the American Society of Nephrol.′s Kidney Week meeting in Philadelphia, the company reported that treatment with Epodure provided more than six months of elevated Hb levels in around half of the trial participants, with the longest effect maintained 30 mo out from treatment.By far the least intrusive therapy would be a pill to treat renal anemia, and San Francisco-based FibroGen is working toward that goal.The company has developed an oral drug that ramps up production of endogenous erythropoietin by stabilizing hypoxia-inducible factor 1α (HIF1α), a protein required for its expression.Although the company abandoned its first HIF1α stabilizer in 2007 after a study participant died of liver failure, preliminary results from an ongoing phase 2 trial look promising.In data announced at last year′s Kidney Week meeting, the company′s second-generation mol., FG-4592, proved more effective and safer than the original.One lingering concern with FibroGen′s approach is that HIF1α affects a number of biol. pathways, not just the production of red blood cells.So, researchers are still waiting on longer-term data to gauge whether the mol. causes any "unintended or undesirable consequences beyond stimulating erythropoiesis," notes Jeffrey Berns, a nephrologist at the University of Pennsylvania Perelman School of Medicine in Philadelphia.Still, the idea that individuals with anemia could one day replace injections with a pill is exciting, Choi says. "We′re going to be waiting with bated breath."