Bristol-Myers stumbles in lung cancer quest as I-O star Opdivo flunks small cell trial

Bristol-Myers Squibb just took another hit to its lung cancer aspirations. Its immuno-oncology blockbuster Opdivo flunked a trial in small cell lung cancer just a few weeks after rival Roche posted a first-line win.

In the CheckMate-331 study, Opdivo failed to top chemotherapy in patients whose cancer had returned after one round of platinum-based treatment, as measured by its ability to help patients live longer. The overall survival numbers weren’t specified.

RELATED: Roche eyes $1B-plus Tecentriq nod with small-cell lung cancer survival win

The shortfall comes just a few months after Opdivo won an FDA approval to treat SCLC after two rounds of treatment, becoming the first PD-1/L1 checkpoint inhibitor to nab an approval in that form of lung cancer.

But it also follows on the heels of Roche’s new data for Tecentriq in previously untreated patients, a much bigger group—and a much bigger sales prospect. SCLC is so difficult to treat that Tecentriq’s median two-month survival improvement over chemo was considered a significant advance. Analysts have estimated Tecentriq could reap an additional $1 billion in sales if it wins a new FDA approval in that group, and Baader Helvea analysts say that number could hit $1.5 billion.

RELATED: Bristol-Myers surprise: Threatened I-O drug Opdivo stands its ground in lung cancer

There are some important differences between the two trials, though, beyond the patient group involved. Roche tested Tecentriq alongside chemo versus chemo alone, while Checkmate-331 pitted Opdivo as a solo treatment against standard-of-care chemo.

And this isn’t Bristol-Myers’ only shot against SCLC with Opdivo. It’s also targeting untreated patients with Opdivo alone and alongside its companion immunotherapy Yervoy.

SCLC is particularly aggressive, with median survival from diagnosis with extensive disease between eight and 13 months, Bristol-Myers says. Some 70% of SCLC patients have extensive disease when they’re first diagnosed. Less than 5% of those patients survive two years.

RELATED: BMS' Opdivo-Yervoy combo posts big win in first-line lung cancer—but big enough to challenge Merck?

Bristol-Myers's CheckMate-331 disappointment comes as Opdivo has fallen behind Merck & Co.'s Keytruda in non-small cell lung cancer. Keytruda has racked up trial wins and new indications in NSCLC, the most prevalent form, putting it ahead of all its rivals in the PD-1/L1 field.

Still, Opdivo has posted significant sales growth; in the second quarter, sales leapt by 36% to $1.63 billion. It's also awaiting a new FDA approval for Opdivo-plus-Yervoy in patients newly diagnosed with NSCLC with a high tumor mutational burden, a new biomarker BMS is touting as key for cancer treatment.