Merck gets ahead of Bristol Myers with fast Keytruda review in esophageal cancer

The FDA has granted priority review to Merck's application for Keytruda in first-line esophageal and gastroesophageal junction cancers. (Merck)

In a potential new front of competition, Merck & Co.’s Keytruda has once again leaped ahead of Bristol Myers Squibb’s rival immunotherapy Opdivo.

The FDA put its application for Keytruda in first-line esophageal cancer in the priority-review fast lane, Merck said Thursday.

The potential new use covers Keytruda in tandem with platinum- and fluoropyrimidine-based chemotherapy as a treatment for previously untreated patients with metastatic esophageal and gastroesophageal junction cancer. With the FDA priority-review tag, Keytruda will know its fate by April 13.

RELATED: ESMO: Merck's Keytruda pushes for 2nd esophageal cancer nod with first-line survival win

The filing is based on data from the phase 3 Keynote-590 trial, which showed the Keytruda regimen slashed the risk of death by 27% and the risk of disease worsening or death by 35% in previously untreated patients. Those on Keytruda lived a median 12.4 months, compared with 9.8 months for chemo alone, according to data presented at this year’s European Society for Medical Oncology virtual congress.

Benefits were observed across patient subgroups, regardless of whether their tumors expressed PD-L1 or whether the cancer was squamous cell carcinoma or adenocarcinoma. In esophageal cancer, Keytruda is currently only allowed in previously treated patients with PD-L1-positive squamous cell disease.

The priority review puts Keytruda ahead of Opdivo, which unveiled its own first-line chemo-combo GI cancer data at the European Society for Medical Oncology's annual meeting. In the CheckMate-649 trial, adding Opdivo to chemo cut the risk of death by 20% as newly diagnosed patients on Opdivo lived a median 13.8 months, versus 11.6 months for solo chemo.

RELATED: ESMO: Bristol Myers' Opdivo racks up GI cancer data for 2 potentially practice-changing FDA nods

But one important difference lies between Keynote-590 and CheckMate-649; in addition to esophageal and gastroesophageal junction cancers, the Opdivo trial also includes gastric cancer patients, a population that Keytruda had previously failed both in the first and second lines. That means, if Opdivo eventually gets an approval based on CheckMate-649, it could be the first in the PD-1/L1 class to enter the front-line stomach cancer setting even though it may fall behind Keytruda in esophageal disease.

Meanwhile, other players are also eyeing the esophageal market. Roche recently kicked off the SKYSCRAPER-08 trial, pairing its Tecentriq with investigational anti-TIGIT immunotherapy tiragolumab and chemo in first-line esophageal cancer.