Zafgen's promising obesity drug comes through in another midstage trial

Zafgen ($ZFGN) charted a third major victory for its in-development obesity drug, spurring weight loss for patients who have endured brain injuries and stoking hopes for success in Phase III.

Treatment with the drug, beloranib, helped sufferers of hypothalamic injury-associated obesity (HIAO) lose significantly more weight than with placebo in a Phase II trial, Zafgen said. Enrolling 14 patients, the company found that those treated with the twice-weekly injection lost an average 7.5 pounds at four weeks and 13.7 pounds at 8 weeks, beating out the placebo group's 0.7 pounds and meeting the study's primary endpoint. Beloranib also proved itself safe and well-tolerated, Zafgen said, and the drug led to demonstrable improvements lipid levels and inflammation, which correlate with cardiovascular disease risk.

With the success in HIAO, Zafgen has now gone 3-for-3 in beloranib's Phase II program. The subcutaneous treatment previously came through in a midstage trial on the rare Prader-Willi syndrome (PWS), which leads to insatiable hunger, and posted excellent results against severe obesity. Now Zafgen is working through a Phase III trial in PWS with eyes on a future FDA filing.

Zafgen Chief Medical officer Dennis Kim

"We are extremely pleased with these results, which differentiate beloranib from other weight-loss agents," Zafgen Chief Medical Officer Dennis Kim said in a statement. "... We believe beloranib shows tremendous potential to improve the lives of those impacted by HIAO and PWS, and for whom there are limited effective pharmaceutical alternatives. In 2015, we aim to establish the regulatory path for a registration program with U.S. and EU regulatory authorities."

Beloranib works by blocking MetAP2, an enzyme involved in fatty acid production, thereby decreasing lipid production in the liver and fat storage while increasing metabolism. The drug's promise helped Zafgen pull off a $103 million IPO last year, and a steady stream of good news has helped the biotech's shares more than double since its debut.

HIAO, an orphan indication, is most commonly the result of surgeries to remove brain tumors, Zafgen said, with as many as 500 new cases cropping up in the U.S. each year.

- read the statement