Stop baricitinib and the preserved beta cell goes with it

Design

post-treatment follow-up of a randomised, double-blind, placebo-controlled trial

Population

88 of 91 participants with recent-onset type 1 diabetes (58 baricitinib, 30 placebo) to week 96

Primary outcome

mixed-meal C-peptide, with HbA1c, insulin dose and CGM measures after treatment cessation at week 48

Effect

C-peptide 0.54 vs 0.38 pmol/mL at week 72 (p = 0.015), 0.43 vs 0.35 at week 96 (p = 0.336); no differences in insulin dose, HbA1c or CGM

The BANDIT trial had shown that 48 weeks of oral baricitinib preserved beta cell function and lowered insulin requirements in recent-onset type 1 diabetes. This follow-up asked what happens when the drug stops. Of 91 randomised participants, 88 reached the week 96 assessment — 58 on baricitinib, 30 on placebo.

Mean C-peptide was still higher in the baricitinib group at week 72 (0.54 vs 0.38 pmol/mL, p = 0.015) but not at week 96 (0.43 vs 0.35, p = 0.336). There were no significant between-group differences in insulin dose, HbA1c or CGM measures at any point during follow-up. The immunological signature went the same way: the reduced frequency and cytokine signalling of effector memory CD8+ T cells seen at week 48 had resolved by week 96. Baricitinib did not correct the paradoxical post-meal glucagon rise. A post hoc comparison suggested adults preserved beta cell function fully after cessation while children lost C-peptide (−0.09 pmol/mL from baseline, p = 0.022), but that is a subgroup split done after the fact.

This changes how the intervention should be described to families. Beta cell preservation in type 1 diabetes is looking less like a course of treatment with a lasting result and more like something that has to be maintained — which is a very different conversation about a drug with ongoing immunosuppressive exposure in a child.

• Describe immunotherapy for new-onset type 1 diabetes as maintenance, not a finite course
• Do not promise durable insulin-sparing from a time-limited trial protocol
• Expect no lasting HbA1c or CGM advantage once the drug is withdrawn
• Treat the adult-versus-child difference as hypothesis-generating when counselling

Why it matters

The treatment works — the difficult part is what happens when it stops.

Don't overread it

The paediatric versus adult difference was a post hoc comparison in small groups, not a prespecified subgroup analysis.

The statistics, in plain English

The week 96 p-value of 0.336 means the difference is compatible with no effect — the groups had converged, not that the drug never worked. The trial was not designed to detect differences after cessation, so the follow-up is descriptive. The adult-versus-child contrast was post hoc, with 28 and 32 participants, and should be treated as a question rather than a finding.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.