I haven't heard them (VPHM) address this , I'm just going by the discussion that's been kicked around here. Have they elaborated on the basis of the claim , or do they just present it as a given?
I suppose you could make the case that when looking for new drug candidates that will likely be used in combo with existing nukes , it might be a better strategy to concentrate on non-nukes ( on the assumption that interference would be less likely).