You can cherry pick a particular time span and claim that halo has not done well. You picked 4 years. Well, how about 1 year (halo up 54% and both NASDAQ and S&P down)? Or how about 3 years (again halo outperformed both indexes)? How about 10 years (again halo outperformed indexes).
Those are too long for you? How about 6 months or year to date?
Too short for you? How about over its entire existence (halo outperformed handily)
You don't have to take my word for it. Do a chart of halo with comps against NASDAQ, S&P or XBI for yourselves.
Regardsing the Astra Zeneca, there may or may not have be an exclusivity barrier. Nonetheless, once MERCK loses the MDASE dispute , Astra Zenca will have to pay halozyme as well. Remember that MDASE patents dont expire until 2034. The only way they can avoid paying halozy is to not bring anything to market until 2034.