(Bloomberg) -- A French drug developer’s experimental therapy slowed the progression of a type of brain cancer by more than 16 months on average, results that could lead to one of the first targeted therapies for the most common form of the tumor in adults younger than age 50.

Closely held Servier Group’s drug held up growth of the tumor, called low-grade glioma, for a median 27.7 months, according to results released Sunday at the American Society of Clinical Oncology meeting in Chicago, compared to 11.1 months for patients who received a placebo. The drug also postponed the time until patients needed additional treatment, such as chemotherapy or radiation, a key secondary goal. So far, most patients who were received Servier’s drug haven’t needed any additional treatment, according to results also being published in the New England Journal of Medicine.

The results from the study of 331 patients are “a very big finding,” says Ingo Mellinghoff, chairman of the neurology department at Memorial Sloan Kettering Cancer Center in New York and one of the leaders of the trial. “It is the first molecularly targeted treatment for diffuse glioma.”  

The drug, called vorasidenib, blocks an enzyme that’s often mutated in low—grade glioma, a slower-moving cousin to glioblastoma, the most aggressive form of brain cancer. Low-grade gliomas usually strike people in their 30s or 40s, growing slowly but relentlessly. After standard surgery, the main treatments are chemotherapy and brain radiation. Patients often postpone these as long as possible, until the tumor inevitably starts to progress.

Servier Group obtained vorasidenib when it agreed to acquire the cancer drug portfolio of Agios Pharmaceuticals Inc. in 2020 for an upfront payment $1.8 billion. The once-daily pill could offer a relatively safe alternative for patients in the prime of life who must weigh whether to take harsh treatments like brain radiation, he says. The trial has not continued long enough to assess whether the drug extends ultimate survival. 

A nurse anesthetist from Emmaus, Pennsylvania, Alicia Kalogeropoulos was diagnosed with low-grade glioma in 2018 when she was 27. 

“I was completely blindsided,” said Kalogeropoulos, now 32. “You know it doesn’t turn out very well” when patients hear the words “brain cancer,” she said.

After deciding to hold off on radiation treatment, she joined the vorasidenib trial in 2020. Her tumor kept growing, and she learned she’d been receiving a placebo. 

But in late 2021 she was allowed to switch over to Servier’s drug, and the tumor growth stopped. She’s had no side effects or symptoms, is able to work full time and hopes to remain on the drug for many years, if not decades.

“When I was on the placebo, you could see this very gradual rise in tumor size, and then all of a sudden very clearly it just plateaued,” she said.  “I am so hopeful for the future.”

David Lee, who heads Servier’s US unit, said the company is working toward filing for Food and Drug Administration approval as soon as possible. When that will be isn’t clear as the company is still gathering follow-up data from the trial and lining up manufacturing partners, he said. Servier said in March that the trial was successful, but the ASCO meeting is the first time details have been released.

The most common side effect in the trial was increased levels of liver enzymes.  

The company is also studying the drug in more advanced cases of glioma that have progressed or recurred, in combination with Merck & Co.’s immunotherapy drug Keytruda.





©2023 Bloomberg L.P.