Deep Remission in Crohn's Disease: When Stopping Becomes the Harder Decision
A single Crohn's disease patient in sustained deep remission on combination therapy, testing whether withdrawing the biologic, the immunomodulator, or neither is the right response to years of quiet disease.
Theo R., a 45-year-old man who works as a high-voltage electrician, has been on combination infliximab and azathioprine for ileocolonic Crohn's disease for just over four years, the last three of them in what his chart genuinely calls deep remission: no symptoms, calprotectin persistently under 50, a follow-up MRI last year showing complete mucosal healing where deep ulceration had been at diagnosis. He climbs transmission towers for a living, a job he'd had to step back from during his worst flares and has since fully returned to, and today's visit is the one he's been building up to for months — asking directly whether, after four years, he still needs to be on two drugs for a disease that by every objective measure isn't doing anything anymore.
It's a fair question with a genuinely uncertain answer, because the actual trial evidence on de-escalation doesn't point to one obviously correct move. STORI, the trial most directly relevant here, studied infliximab withdrawal specifically in patients already in sustained remission on combination therapy and found that roughly half relapsed within a year of stopping the biologic, with identifiable predictors — elevated CRP, low hemoglobin, and endoscopic findings at the time of withdrawal among them — that helped separate lower-risk from higher-risk candidates for the attempt. What STORI didn't test directly is the mirror question Theo is also implicitly asking: whether stopping the azathioprine instead, and continuing infliximab alone, might preserve his remission just as well while removing the drug whose own risks — lymphoma, skin cancer, myelosuppression — accumulate the longer it's continued. Four years of quiet disease is real evidence something in this regimen is working. It doesn't, on its own, say which half of it is doing the work, and Theo's own framing of the question — not "can I stop everything" but "do I still need both" — is more precise than either trial was actually designed to answer directly.
Clinic, discussing withdrawal after 4 years
I'd withdraw the azathioprine and continue infliximab alone. Combination therapy's main benefit is concentrated early, reducing anti-drug antibody formation during induction and the first year or two of maintenance — four years in, with a clean immunogenicity profile the whole way, that purpose has likely already been served. Thiopurine risks, lymphoma and skin cancer in particular, accumulate with duration of use, which argues for stopping the one drug whose risk actually grows the longer he stays on it, not the one that's controlling his disease.
I'd look at this the other direction. STORI is the trial that actually tested this question — infliximab withdrawal in patients already in sustained combination-therapy remission — and Theo's own numbers land favorably against its identified predictors of relapse: normal CRP, normal hemoglobin, and complete mucosal healing on his last MRI, not just clinical quiet. That's real, specific evidence for withdrawing the biologic specifically, not azathioprine, which STORI didn't test in reverse.
I want to name the option neither of you is proposing but that I think deserves real weight: changing nothing. Roughly half of STORI's patients relapsed within a year of stopping infliximab — that's not a reassuring number, it's a coin flip on a remission that took years to reach and that Theo has rebuilt his entire working life around. I take both of your arguments seriously as reasons a withdrawal attempt could reasonably succeed for him specifically. What I'm less convinced of is that succeeding matters more to him than the downside if it doesn't — and that's genuinely his call to make, not something either mechanism argument settles on its own.
Not agreed today, deliberately: the team presented Theo with the actual tradeoff rather than choosing for him — STORI's real relapse data if infliximab is withdrawn, the accumulating-risk argument for withdrawing azathioprine instead, and the option of changing nothing at all — and asked him to take the summary home rather than decide in the room.
Infliximab withdrawal proceeds per STORI's protocol, with close monitoring for the specific relapse predictors flagged in the trial and a plan to restart promptly if early signs appear.
Combination therapy continues unchanged, revisited at the next annual visit rather than reopened again this year.