Bristol-Myers Squibb has an expanded indication for squamous non-small cell lung cancer in hand three business days after landing Priority Review status for its then-melanoma drug Opdivo (nivolumab).

“We knew the approval was likely to be fast by the FDA, but this was very fast,” Sanford C. Bernstein analyst Tim Anderson wrote in a research note Wednesday.

The drugmaker was looking at a June approval date just last week.

Opdivo is part of the new PD-1 class of immuno-oncology drugs that includes Merck’s melanoma drug Keytruda (pembrolizumab). The two drugs have  been in a tight race since the beginning. Anderson noted that BMS’s NSCLC drug lead may be a short one since Merck is expected to submit its lung-cancer indication request by the middle of this year.

Wednesday’s approval means Opdivo can be used as a second-line treatment. EvercoreISI analyst Mark Schoenebaum wrote in a summary that the $12,500-per-month drug may be appropriate for a pool of 100,000 second-line patients.

Duration of therapy has yet to be determined, but Leerink analyst Seamus Fernandez noted that the drug’s reach could be sizable because the label does not include a PD-1 biomarker restriction.

“This removes any doubt about the FDA restricting the patient population for Opdivo,” he wrote, adding that this is of particular importance because Roche and Merck “primarily studied their PDL1 and PD1 antibodies in PDL1 biomarker positive patients.” The FDA granted Roche’s experimental PD-L1, MPDL3280A, Breakthrough Therapy status in February.

Bristol-Myers Squibb already has a sales force in place. The company told MM&M in January it had “increased the size of our field teams, both sales and medical to ensure that we have the right resources if we receive approval for a lung-cancer indication.”