"This Phase 3 study shows superior PFS (progression-free survival) with first-line combination immunotherapy in a predefined population of NSCLC patients with high TMB (tumor mutation burden)," Dr. Matthew D. Hellmann, study investigator and medical oncologist at Memorial Sloan Kettering Cancer Center, said in a press release.
Dr. Giovanni Caforio, chairman and chief executive officer of Bristol-Myers Squibb, said that his company sees the results as "a breakthrough in cancer research and a meaningful step forward in determining which first-line lung cancer patients may benefit most from the combination of Opdivo and Yervoy."
"These findings attest to our deep understanding of cancer biology, leading translational medicine capabilities and commitment to developing new approaches for cancer patients," he added.
The treatment trials are currently in their final phase, meaning the next step is to seek approval from the Food and Drug Administration to market the drug combination as a treatment for this specific condition. A panel of experts formed to assess the data recommended that the clinical trial move forward, despite some modifications made during the trial, according to the company.
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Bristol-Myers Squibb has been a pioneer in immunotherapy, according to Reuters. But some analysts are still holding out to see whether or not the treatment will be a success.
"Overall survival is what matters," BMO Capital Markets analyst Alex Arfaei said, explaining that regulators prefer that standard.
"The survival benefit may not be that great," he added, pointing to other new promising treatments.
One analyst called the study "a clear win" for the company, but another cautioned that the report is "positive but unquantified data," according to Bloomberg.
Critics questioned whether the pharmaceutical company’s clinical trial design change may have sullied the results.
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According to MarketWatch, researchers made changes to the Phase 3 trial, called CheckMate-227, while it was already ongoing.
Bristol-Myers management addressed the concerns Monday in a conference call, stating that it responded to emerging science and only made changes after conversations with the Food and Drug Administration.
Nonetheless, the company is hailing the trials as "a true example" of "innovation."
Overall survival data from the Opdivo and Yervoy combination trial will be released near the end of 2018 or early in 2019 the company said.
Already, Opdivo is the company's best-selling drug, reporting sales of $4.95 billion globally last year.
"By harnessing the body's own immune system to fight cancer, Opdivo has become an important treatment option across multiple cancers," Bristol-Myers Squibb explained.
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The new trials will likely increase the drug's profitability as they further demonstrate its benefits, the company said. However, Seamus Fernandez, an analyst at Leerink Partners, pointed out that it remains to be seen whether combining Opdivo with Yervoy provides better results than taking the drug alone.
For now, Bristol-Myers Squibb is thanking the patients who participated in the trial leading to the "breakthrough."
"We would like to thank the patients and researchers who participated in these clinical trials — without whom this scientific advance would not be realized," the company said in a statement.