I believe Duffy saw an opportunity to be useful advising on how they navigate toward the biomarker approval trials they clearly want to do. And the company thought he would or could be useful. I do not doubt that his interest was peaked because of the combination trials that were in the works and the likelihood of synergies. I think he was quietly on loan from Merck, because some have indicated he never moved to Maryland.
However, when the CEO left, I think he realized he was extremely valuable at companies with competing products and he sought to monetize that happy circumstance. There is nothing wrong with that. Most people who have unique knowledge would do the same.
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