Re: GSK call
I largely agree with you. I'd say GSK has near Messianic faith in their Shingrix adjuvant and probably have not bought NVAX yet because (1) NVAX keeps failing its P3 trials, and (2) they hope that the Shingrix adjuvant in combo with their own RSV or Flu vaccine may show great promise in some P2 and they won't have to buy NVAX
My guess is GSK has left it like this "Call us if you get an offer. Allow us to counter-offer"
That way GSK spends no upfront money on NVAX operations while maintaining a free and infinite "call" option on the assets by way of counter-offer. in the meantime they work towards developing homegrown assets into winners. If they produce a winner in RSV they don't have to give it away for cheap to GAVI/BMGF - as just one example of an upside
I'm not expecting much more than $2b, per your estimate. Only. a bidding war takes it higher.
GSK found out the hard way with Advair that billion dollar franchises don't just grow on trees. I'd be stunned if they let someone come along and eat their lunch on Flu when they could move towards dominance. They only way this happens is if some must-buy immune-onccology company comes available and they just have to spend their remaining cash on it. For example if they just have to buy NXTC, perhaps they pass on NVAX even if Nanoflu is a success.