| April 6
April 6 An experimental drug being developed by
Agios Pharmaceuticals Inc showed promising anti-cancer
activity in a tiny Phase I study of patients with relapsed acute
myeloid leukemia (AML), according to data presented on Sunday.
Of seven patients available to be evaluated following a
28-day cycle of treatment with the drug, AG-221, six had what
researchers deemed objective responses to the medicine.
Three of them achieved complete remission and two achieved
complete remission with incomplete platelet recovery, meaning
that the leukemia had exited their bone marrow but the blood
platelet count had not yet returned to normal levels.
"I'm very excited about what has happened with those
patients so far who have responded," the study's lead
investigator, Dr. Eytan Stein of Memorial Sloan Kettering Cancer
Center in New York, said in a telephone interview.
AML, the most common type of acute leukemia in adults, is a
cancer of the blood and bone marrow that progresses quickly if
left untreated. AG-221 targets a gene mutation that is present
in 10 percent to 15 percent of AML patients, Stein explained.
Stein, who presented the results at the American Association
for Cancer Research (AACR) meeting in San Diego, cautioned that
this was very preliminary data.
"If the results are confirmed (in upcoming larger trials)
that would be a remarkably exciting result," Stein said of the
Patients in the study had AML that had progressed after, or
failed to respond to, up to four other therapies.
They all had the specific genetic mutation in the leukemic
cells that the drug is designed to impact, called isocitrate
dehydrogenase-2, or IDH2. The treatment led to substantially
lower levels of a cancer metabolite in the blood called 2HG that
researchers believe reprograms white blood cells, stripping
their ability to become infection fighters.
Stein noted that in the tiny group of patients there were no
observable side effects that appear related to the drug itself,
"which is very different from chemotherapy."
Patients in the study received either 30 milligrams or 50 mg
of AG-221 twice a day. Another arm of the trial was studying two
higher doses, but that data was not yet available.
Stein said researchers were not expecting the impact seen
with the lowest doses in the first handful of patients.
"We were actually kind of surprised that at the first dose
level we're seeing dramatic clinical activity. That usually
doesn't happen," he said.
(Reporting by Bill Berkrot; Editing by Raissa Kasolowsky)