Cost-effectiveness analysis of increased adalimumab dose intervals in Crohn's disease patients in stable remission:The Randomized Controlled LADI Trial

BACKGROUND AND AIMS: 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, randomised controlled non-inferiority trial, comparing increased adalimumab intervals with the two-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 randomised 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, [-2,226; €1,367] over the 48-week study period between the two groups. Medication costs per patient were lower (-€2,545, [-€2,780; -€2,192]) in the intervention group, but non-medication healthcare (+€474, [+€149; +€952]) and patient costs (+€365 [+€92; €1,058]) were higher. Cost-utility analysis showed that the iNMB was €594 ([-€2,099; €2,050]), €69 [-€2,908; €1,965], and -€455 [-€4,096; €1,984] at WTA levels of €20,000; €50,000; and €80,000. Increasing adalimumab dose intervals was more likely to be cost-effective at WTA levels below €53,960 per QALY. 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

Increased versus conventional adalimumab dose interval for patients with Crohn's disease in stable remission (LADI): a pragmatic, open-label, non-inferiority, randomised controlled trial

Background: Despite its effectiveness in treating Crohn's disease, adalimumab is associated with an increased risk of infections and high health-care costs. We aimed to assess clinical outcomes of increased adalimumab dose intervals versus conventional dosing in patients with Crohn's disease in stable remission. Methods: The LADI study was a pragmatic, open-label, multicentre, non-inferiority, parallel, randomised controlled trial, done in six academic hospitals and 14 general hospitals in the Netherlands. Adults (aged ≥18 years) diagnosed with luminal Crohn's disease (with or without concomitant perianal disease) were eligible when in steroid-free clinical and biochemical remission (defined as Harvey-Bradshaw Index [HBI] score <5, faecal calprotectin <150 μg/g, and C-reactive protein <10 mg/L) for at least 9 months on a stable dose of 40 mg subcutaneous adalimumab every 2 weeks. Patients were randomly assigned (2:1) to the intervention group or control group by the coordinating investigator using a secure web-based system with variable block randomisation (block sizes of 6, 9, and 12). Randomisation was stratified on concomitant use of thiopurines and methotrexate. Patients and health-care providers were not masked to group assignment. Patients allocated to the intervention group increased adalimumab dose intervals to 40 mg every 3 weeks at baseline and further to every 4 weeks if they remained in clinical and biochemical remission at week 24. Patients in the control group continued their 2-weekly dose interval. The primary outcome was the cumulative incidence of persistent flares at week 48 defined as the presence of at least two of the following criteria: HBI score of 5 or more, C-reactive protein 10 mg/L or more, and faecal calprotectin more than 250 μg/g for more than 8 weeks and a concurrent decrease in the adalimumab dose interval or start of escape medication. The non-inferiority margin was 15% on a risk difference scale. All analyses were done in the intention-to-treat and per-protocol populations. This trial was registered at ClinicalTrials.gov, NCT03172377, and is not recruiting. Findings: Between May 3, 2017, and July 6, 2020, 174 patients were randomly assigned to the intervention group (n=113) or the control group (n=61). Four patients from the intervention group and one patient from the control group were excluded from the analysis for not meeting inclusion criteria. 85 (50%) of 169 participants were female and 84 (50%) were male. At week 48, the cumulative incidence of persistent flares in the intervention group (three [3%] of 109) was non-inferior compared with the control group (zero; pooled adjusted risk difference 1·86% [90% CI –0·35 to 4·07). Seven serious adverse events occurred, all in the intervention group, of which two (both patients with intestinal obstruction) were possibly related to the intervention. Per 100 person-years, 168·35 total adverse events, 59·99 infection-related adverse events, and 42·57 gastrointestinal adverse events occurred in the intervention group versus 134·67, 75·03, and 5·77 in the control group, respectively. Interpretation: The individual benefit of increasing adalimumab dose intervals versus the risk of disease recurrence is a trade-off that should take patient preferences regarding medication and the risk of a flare into account. Funding: Netherlands Organisation for Health Research and Development