AACR: Bristol Myers' Opdivo one-ups Merck's Keytruda with presurgery lung cancer win

Bristol Myers Squibb’s Opdivo may be less popular than Merck & Co.’s Keytruda among physicians treating non-small cell lung cancer, but it has just notched an important clinical win for earlier use that its archrival can’t yet tout.

Patients with early-stage non-small cell lung cancer who took a combination of Opdivo and chemotherapy before surgery were nearly 14 times more likely to show no signs of cancer cells in their resected tissue compared with those who got chemo alone. The results were shared at the American Association for Cancer Research annual meeting.

Bristol Myers was quick to point out that the data, coming from the phase 3 CheckMate-816 trial, represents the first time that presurgery use of a PD-1/L1 combo showed a significant improvement in the so-called complete pathological response in patients with NSCLC that could be surgically removed.

The study enrolled patients with stage IB to IIIA NSCLC. While 24% of Opdivo-chemo takers enjoyed no residual viable tumors in their resected tissues and lymph nodes, only 2.2% of patients on solo chemo could say the same.

An improvement greater than 20% is “meaningful and encouraging” and serves as “an early indicator of the potential for long-term outcomes,” Mark Rutstein, who leads Opdivo development at Bristol, said in an interview.

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Rutstein declined to comment on the company’s regulatory path from here—specifically, whether the company plans to use just these pathological response data for a filing with the FDA. The study remains ongoing to see if the Opdivo-chemo regimen can prevent tumors from returning—the study’s co-primary endpoint—or if it can extend patients’ lives.

No major difference in efficacy stood out among different key patient subgroups, Rutstein pointed out. Similar benefits were shared among patients with different PD-L1 expression levels, across the disease stages, as well as with squamous or non-squamous disease.

What’s more, adding Opdivo didn’t hurt patients’ eligibility for surgery; 83% of patients on Opdivo underwent surgery, versus 75% for chemotherapy.

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Moving treatment to early-stage cancer before or after surgery in the neoadjuvant and adjuvant settings represents the next frontier for PD-1/L1 inhibitors, as the class has successfully established new treatment standards for many metastatic diseases.

The idea is that early use of immunotherapy might prevent cancer from returning. When a patient’s disease recurs in the early-stage setting, it marks the transition from a curable state to incurable, Rutstein explained. In NSCLC, up to 55% of patients will recur after surgery, representing a high unmet need, he said.

With the latest CheckMate-816 victory, Bristol now has four wins under its belt in neoadjuvant and adjuvant use. It already bears an approval for use after surgery in melanoma. In another first-in-class win, post-surgery use of Opdivo recently showed it could cut the risk of disease returning or death by 30% over placebo in high-risk muscle-invasive urothelial carcinoma. The drug also topped placebo in adjuvant esophageal cancer, fending off a recurrence for almost two years in the CheckMate-577 trial.

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The CheckMate-816 trial previously had another arm combining Opdivo and Bristol’s CTLA4 inhibitor Yervoy. But the company stopped enrollment in that arm for “expediency and pragmatism” after seeing encouraging data from an outside study for the Opdivo-chemo cocktail, Rutstein explained, saying that the decision predated results from the Checkmate-915 trial, which showed the Opdivo-Yervoy pairing wasn’t better than Opdivo alone in adjuvant melanoma.

Bristol’s also conducting the CheckMate-77T trial, testing whether adding Opdivo in both neoadjuvant and adjuvant settings can stave off cancer recurrence in stage IIA to IIIB NSCLC.

Other PD-1/L1 players are eyeing early NSCLC use as well. Merck has the Keynote-671 trial for neoadjuvant Keytruda and chemotherapy plus adjuvant Keytruda. Roche has a similar Impower030 trial for Tecentriq, and AstraZeneca for Imfinzi.