I heard about this likelihood about a month ago, but why do you think the market viewed this as a positive?
My guess: Since the FDA did not announce the convening of an advisory panel for Eliquis when it extended the PDUFA date, investors are inferring that there will not be a panel. Whether the lack of a panel is bullish or bearish is debatable, of course; however, when implicit information about the lack of a panel is coincident with a PDUFA extension, as it was in this instance, it’s somewhat more bullish than bearish, IMO.
Moreover, the Eliquis data package in AF/stroke prevention is extremely strong, so it’s reasonable to assume that the PDUFA extension itself is merely procedural—i.e. a consequence of BMY/PFE’s submitting additional data after the NDA filing.
“The efficient-market hypothesis may be the foremost piece of B.S. ever promulgated in any area of human knowledge!”