It ain't over till its over.
It should also be noted that Merck took the SHORT, EASY way around in the drug study. They used patients with a protein that potentiated Keytruda. BMY took the HONEST approach with difficult patients who had low protein types that DID NOT ARTIFICIALLY AID the drug.
It is quite possible that Opdivo IS STILL A BETTER DRUG than Keytruda.
BUT because BMY DOES NOT CUT CORNERS (Like Merck) in drug studies, the market rewards cheating, lying companies like Merck and NOT honest companies like Bristol Myers Squibb.