Stifel analyst Adam Walsh last night upgraded Protagonist Therapeutics to Buy from Hold and raised his price target for the shares to $17 from $11. The expansion of the deal between Protagonist and Janssen for PTG-200 and other IL-23 receptor antagonists brings large pharma validation to the former's oral peptide platform, Walsh tells investors in a research note. The analyst now has increased confidence in PTG-200. Janssen's decision to opt-in to further PTG-200 development is supportive of PTG-200's potential in Crohn's and should assuage investor fears around Protagonist's oral peptide technology, says the analyst.