Cost-Effectiveness Analysis of Increased Adalimumab Dose Intervals in Crohn's Disease Patients in Stable Remission: The Randomized Controlled LADI Trial.

Background and aims: We aimed to assess cost-effectiveness of increasing adalimumab dose intervals compared to the conventional dosing interval in patients with Crohn's disease [CD] in stable clinical and biochemical remission.

Design: We conducted a pragmatic, open-label, randomized controlled non-inferiority trial, comparing increased adalimumab intervals with the 2-weekly interval in adult CD patients in clinical remission. Quality of life was measured with the EQ-5D-5L. Costs were measured from a societal perspective. Results are shown as differences and incremental net monetary benefit [iNMB] at relevant willingness to accept [WTA] levels.

Results: We randomized 174 patients to the intervention [n = 113] and control [n = 61] groups. No difference was found in utility (difference: -0.017, 95% confidence interval [-0.044; 0.004]) and total costs (-€943, [-€2226; €1367]) over the 48-week study period between the two groups. Medication costs per patient were lower (-€2545, [-€2780; -€2192]) in the intervention group, but non-medication healthcare (+€474, [+€149; +€952]) and patient costs (+€365 [+€92; €1058]) were higher. Cost-utility analysis showed that the iNMB was €594 [-€2099; €2050], €69 [-€2908; €1965] and -€455 [-€4,096; €1984] at WTA levels of €20 000, €50 000 and €80 000, respectively. Increasing adalimumab dose intervals was more likely to be cost-effective at WTA levels below €53 960 per quality-adjusted life year. Above €53 960 continuing the conventional dose interval was more likely to be cost-effective.

Conclusion: When the loss of a quality-adjusted life year is valued at less than €53 960, increasing the adalimumab dose interval is a cost-effective strategy in CD patients in stable clinical and biochemical remission.

Clinical trial registration number: ClinicalTrials.gov, number NCT03172377.