It's true that biologics can wear off, but two counterpoints: (1) with the wealth of options available on the market today, you can generally hop to a new drug if a particular formulation starts losing its effectiveness, and (2) even if you only got Three Glorious Years of relief before all biologics stopped working for you forever, isn't that still a net gain versus not going on them at all?

For what it's worth, though, many people don't develop resistance, or at least not for a loooong time. My gastro told me one patient of his has been on Remicade for 15+ years and it's put them in happy remission the whole time.

Not everyone's a success story, but the success stories are very very good.