Agios' AG-221 racks up more cancer remissions, setting the stage for a pivotal challenge

Just a few months after Agios Pharmaceuticals highlighted clear indications of success for its early-stage drug AG-221 for various blood cancers, the biotech has followed up with a bonus round of promising results at the annual scientific meeting of the American Society of Hematology. Investigators noted that a growing number of patients with IDH2-mutant positive malignancies have achieved a complete response, with the durability of the response extending out now to 8 months in some cases. And the clinical success is opening the door to a registration study now planned to launch in 2015.

The Phase I dose escalation, single agent trial has now counted an evaluable response from 25 of 45 patients suffering from hard-to-treat acute myeloid leukemia, myelodysplastic syndrome, chronic myelomonocytic leukemia and untreated AML who had declined intensive chemotherapy. Investigators counted 6 complete remissions, nine complete remissions "with various degrees of hematologic recovery" and 10 partial remissions. Nine out of 10 patients had responses lasting from three months to as long as 8 months and ongoing.

The news also marks a boost for Celgene, which followed up on its early partnership by grabbing an option on the drug with a $130 million upfront payment.

Cambridge, MA-based Agios ($AGIO) is operating with a game plan established by David Schenkein, a noted cancer drug researcher and Genentech vet who has become one of the leaders in adaptive trial design, in which drugs can be sped through a compact, blended series of studies capable of delivering solid evidence of efficacy and safety. With the outspoken support of FDA cancer czar Richard Pazdur, studies like this are cutting months and sometimes years out of the development process. And the biotech, a 2009 Fierce 15 biotech, said today that it is mapping out a pivotal program for this drug that can launch next year, with its other clinical-stage drug--the IDH1-mutant inhibitor AG-120--advancing into a registration program in 2016.

Eytan Stein

"These findings build upon those presented throughout the year," says Eytan Stein, the lead investigator and a physician at Memorial Sloan Kettering Cancer Center. "In addition, they continue to provide evidence that AG-221 can inhibit the IDH2 mutant protein, stop production of the oncometabolite, 2-HG, and allow for cancer cells to become mature, functioning blood cells. This approach is different from traditional chemotherapy that attempts to non-selectively kill cancer cells. I believe AG-221's unique mechanism targeting a specific mutation is the way of the future and represents a highly specific oral therapy that may transform the treatment of a devastating group of blood cancers."

- here's the release

Special Report: 2009 Fierce 15 - Agios Pharmaceuticals