In a study out this week, scientists describe a novel experimental pill that may be able to help patients with a difficult-to-treat form of leukemia. Nearly half of patients in the Phase I trial responded to the treatment, called revumenib, while about a third experienced a complete remission of their cancer. More research will be needed to confirm its effectiveness, however.
Revumenib is being developed by the company Syndax. It’s meant to work by inhibiting a protein called menin, which seems to play an important role in certain forms of leukemia. These cancers are characterized by carrying a NPM1 gene mutation or a rearrangement of another gene, called KMT2A. These aberrations are commonly found in both pediatric and adult cases of leukemia and are often very hard to treat. According to research cited by the scientists, for instance, the five-year survival rate for KMT2A-related leukemia is less than 25%.
On Thursday, these researchers published results from the first human trial of revumenib in the journal Nature. The trial enrolled 68 patients with relapsed or refractory acute leukemia that had failed to respond to previous treatments. Most of these patients had NPM1/KMT2A-related cancer.
Phase I trials are designed to test the safety and optimal dose of an experimental treatment. But to understand its potential efficacy, the team also looked at the outcomes of those with NPM1/KMT2A-related leukemia (60 in total). Out of these eligible patients, 53% showed some response to revumenib, and about 30% (18 patients) showed complete remission. Though nearly all of the patients experienced adverse effects, including potentially serious ones like an irregular heartbeat, none had to stop treatment as a result.
“For patients with acute leukemia who have undergone several previous treatments, this is a very encouraging result,” said study author Scott Armstrong, president of the Dana-Farber and Boston Children’s Cancer and Blood Disorders Center, in a statement released by Dana-Farber.
G/O Media may get a commission
Phase I trials are only the start of clinical development, and many drugs that show encouraging results early on fail to fulfill that promise in larger trials. And even if revumenib does prove to be largely effective against these cancers, it may not be long-lasting for some. In a second study looking at the trial data, also released this week in Nature, the researchers found that some patients’ cancers adapted to the treatment and developed resistance to it.
These findings are both good and bad news, the authors say. It’s good, since it shows these cancers truly rely on menin to fuel their growth and likewise that drugs capable of disturbing how the protein is used by these cancers can neuter them. At the same time, it also likely means that other strategies will be needed to delay or prevent resistance against these drugs. That could include treating people at an earlier stage of cancer or pairing revumenib with other types of drugs that attack these cancers from a different angle.
An expansion of the study is already underway, with full Phase I/II results expected later this year. Should things continue to go well, the company has said it may start to file for FDA approval as early as the end of 2023. If approved, revumenib would be the first menin inhibitor to treat cancer.