The US Food and Drug Administration has agreed to review Bristol-Myers Squibb’s PD-1 inhibitor Opdivo (nivolumab) as a treatment for advanced squamous non-small cell lung cancer (NSCLC) after prior therapy.

The regulator also said it would undertake a priority review of the application, and that the Prescription Drug User Fee Act goal date for a decision is June 22, 2015.

The submission is based on data from the Phase II trial CheckMate-063, in which the estimated one-year survival rate was found to be 41% in patients given the drug.

Opdivo has a good shot at becoming the first immunotherapy cleared for the treatment of advanced squamous NSCLC. But Merck & Co's rival Keytruda (pembrolizumab) could be hot on its heels - the company recently said it would be fiing its immunotherapy in the first half of this year.

Opdivo is already on the US market to treat unresectable or metastatic melanoma in patients with disease progression, following treatment with Yervoy (ipilimumab).