Updated from Sunday at 10:30 am EDT with current stock price, analyst comments.
SAN DIEGO (TheStreet) -- The Agios Pharmaceuticals (AGIO) cancer metabolism drug AG-221 is demonstrating surprisingly strong clinical activity, including multiple complete remissions, in an early stage study involving patients with advanced blood cancers.
Shares of Agio were up 30% to $46.25 in Monday pre-market trading.
Agios designed AG-221 to block a mutated protein known as IDH2 which promotes the growth of cancer cells. The phase I study presented Sunday was expected to demonstrate the ability of AG-221 to decrease levels of an IDH2 biomarker as proof of early activity.
AG-221 achieved that and more. Six of 10 patients with advanced, treatment-refractory acute myeloid leukemia carrying the IDH2 mutation had objective tumor responses, including three complete remissions and two complete remissions with incomplete platelet recovery.
"We are very encouraged by these early data," said Agios CEO David Schenkein, in a statement. "The findings corroborate the use of precision medicine in genetically defined patient populations..."
The AG-221 data were presented Sunday at the American Association for Cancer Research (AACR) annual meeting.
The phase I study is enrolling patients with acute myeloid leukemia (AML) or myelodysplastic syndrome which no longer responds to multiple lines of therapy. All the patients were screened to make sure their cancer harbored the IDH2 mutation.
Ten AML patients were treated in the first two cohorts of the study with either 30 mg or 50 mg of AG-221 given orally twice per day. After a single, 28-day treatment cycle, three patients achieved a complete remission, as determined by study investigators. Two patients had a complete remission with incomplete platelet recovery and a single patients achieved a partial response.