Merck Drug Found to Extend Lives of Brain-Cancer Patients

(Bloomberg) -- Patients with the same aggressive brain cancer that killed U.S. Senator John McCain saw survival time double after being treated with Merck & Co.’s blockbuster immunotherapy drug Keytruda before surgery to remove a tumor.

Researchers at the University of California at Los Angeles seeking new treatments for the cancer, called recurrent glioblastoma, found that patients who were treated with Keytruda before the removal of a brain tumor survived an average of 417 days -- nearly double the historic average for the deadly disease.

The results are the first findings to suggest that a class of cancer treatments called checkpoint inhibitors, which unleash the immune system to attack malignant cells, benefit glioblastoma patients. Although the clinical trial evaluated only 35 patients and didn’t have a control group, the results will arm scientists with information to launch new trials.

“Everyone is very excited,” said Robert Prins, a professor of neurosurgery at UCLA’s Jonsson Comprehensive Cancer Center and senior author of the study. “It’s the first signal we’ve seen of the clinical benefit, but we don’t want to jump to conclusions that we’ve cured this kind of tumor. What it did was give us important information that the timing of treatment mattered.”

Prins said the study wasn’t designed to look at survival but rather to better understand how immunotherapy affects a brain tumor. Of the 35 patients evaluated, 16 received the immunotherapy both before and after surgery, while 19 received the treatment only after the operation.

Patients who received treatment only after surgery didn’t see much benefit, surviving an average of 228 days, which is in line with the current expectancy.

Merck shares fell 0.9 percent to $76.86 at 1:11 p.m. in New York. The stock is up 0.6 percent for the year.

Expanding Trials

Due to the success of the trial, Prins and his colleagues said they’ve reached an agreement with Merck to expand the presurgery immunotherapy treatment to an additional 25 patients within the first half of the year. In other clinical trials, melanoma and lung-cancer patients have also seen prolonged lifespan following presurgery treatment, according to the researchers.

Merck has seen Keytruda sales boom to more than $7 billion a year amid an increasingly competitive market for innovative treatments that target many types of cancer. The drug has slugged it out with Bristol Myers Squibb Co.’s Opdivo as both companies vie for the market lead in immuno-oncology. Pfizer Inc., GlaxoSmithKline Plc and Novartis AG are also investing heavily in cancer therapies.

“Merck has done an excellent job of making Keytruda the envy of its immuno-oncology peers, with a string of clinical-trial wins conferring a halo effect, and physicians are likely to think of prescribing the drug first,” said Sam Fazeli, a Bloomberg Intelligence global pharmaceutical analyst, in a note.

Prins said the Jonsson Comprehensive Cancer Center is looking to treat recurrent glioblastoma patients with Bristol-Myer’s Opdivo, as well.

“Currently, there is no true standard of care for recurrent glioblastoma,” Prins said. “But we are believers in immunotherapy. We’re excited to expand the basis of the science.”

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