Filgotinib for Moderate to Severe Rheumatoid Arthritis: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

Filgotinib in rheumatoid arthritis

INTRODUCTION

Rheumatoid Arthritis (RA) remains a challenge for rheumatologists and patients despite implementation of intensive treat-to-target strategies in shared decision with patients and an increasing availability of drugs. Janus kinase inhibitors (JAKi) are a new generation of oral targeted drugs. Filgotinib preferentially inhibits JAK1 and is the latest JAKi to be approved for use in RA.

AREAS COVERED

This narrative review focuses on drug characteristics, efficacy, and safety of filgotinib in patients with RA, summarizing available literature. Trial data are detailed, put into perspective for practice and discussed in regulatory perspective.

EXPERT OPINION

Preclinical studies demonstrate preferential inhibition of JAK1 and a promising pharmacokinetic profile with few drug-drug interactions. Increase in hemoglobin in line with preferential inhibition of JAK1 over JAK2 is seen in early-phase clinical trials. A phase III program demonstrates efficacy in several disease stages, numerically higher with 200 mg versus 100 mg daily. In the overall RA population such dose-related effect is not observed for safety except for herpes zoster and increases in lipids and creatine phosphokinase. This reassuring safety profile is to be confirmed in future practice. It also needs to be unraveled if JAK1 preferential inhibition plays a key role in this safety profile.

Cost-effectiveness of janus kinase inhibitors for rheumatoid arthritis: A systematic review and meta-analysis of cost-utility studies

Introduction: Janus kinase inhibitors (JAK-i), a class of targeted synthetic disease-modifying antirheumatic drugs (tDMARDs), are suggested as second or third-line therapies in rheumatoid arthritis (RA). Synthesized cost-effective evidence would aid in informed decision-making given the similar clinical effectiveness of JAKi, but incongruent cost-effectiveness reports. Methods: Literature search was conducted in PubMed, Embase, Scopus, and Tufts Medical Centers' cost-effective analysis registry. We pooled the incremental net benefit (INB) with 95% confidence interval (CI) using random-effects model and the heterogeneity was assessed using Cochrane-Q test and I2 statistic. Modified economic evaluation bias checklist was used to assess the quality of selected studies. Publication bias was assessed using a funnel plot and Egger's test. The Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) assessment was performed to assess the certainty of outcomes presented. Results: We included seventeen relevant studies for systematic review, of which fifteen were eligible for meta-analysis. The meta-analysis results showed that JAK-i is cost-effective compared to csDMARDS/bDMARDs with a pooled INB (INBp) of $19,886 (95% CI, 1,635 to 38,137) but with considerable heterogeneity (I2 = 99.14). As a second-line treatment for csDMARD failed RA, JAK-i is cost-effective than csDMARD/bDMARD with a pooled INB of $23,144 (74.1-46,214) and high heterogeneity (I2 = 99.67). But on a separate analysis JAK-i as second-line treatment is not cost-effective than TNF-a-i (INBp = $25,813, -5,714 to 57,340). However, leave-one-out analysis found that omitting a single outlier makes JAK-i cost-effective. Further, JAK-i is not cost-effective as a third-line treatment for csDMARD-TNF-a-I failed RA, compared to csDMARDs/bDMARDs with INBp $26,157 (-7,284 to 59,598). Conclusion: Meta-analysis suggests that JAK-i is cost-effective when used after csDMARD failure but not cost-effective when used after csDMARD-TNF-a-i failure with low certainty of evidence. Clinical Trial Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021222541, identifier CRD42021222541.