Number needed to treat and cost per responder of Janus kinase inhibitors approved for the treatment of moderate-to-severe rheumatoid arthritis in Japan

Mod Rheumatol. 2023 Jan 3;33(1):54-63. doi: 10.1093/mr/roac015.

Abstract

Objective: This study evaluated the effectiveness and cost-effectiveness of baricitinib, tofacitinib, and upadacitinib regimens, compared to conventional synthetic disease-modifying antirheumatic drug (csDMARD) alone, among Japanese patients with moderate-to-severe rheumatoid arthritis (RA) inadequately responsive to csDMARD, measured in terms of number needed to treat (NNT) and cost per responder (CPR).

Methods: Efficacy data were derived from two recent network meta-analyses among global and Japanese population. The cost perspective was that of the Japanese Health Service. Both NNT and CPR were based on disease activity score for 28 joints with C-reactive protein (DAS28-CRP) remission and American College of Rheumatology (ACR) 20/50/70 at 12 and 24 weeks.

Results: Over 12 weeks, the median NNT and the median CPR to achieve DAS28-CRP remission were 4.3 and JPY 1,799,696 [USD 16,361], respectively, for upadacitinib 15 mg + csDMARD. The equivalent results were 6.0 and JPY 2,691,684 [USD 24,470] for baricitinib 4 mg + csDMARD and 5.6 and JPY 2,507,152 [USD 22,792] for tofacitinib 5 mg + csDMARD. Similar rankings were observed at 24 weeks and for other outcomes.

Conclusions: Upadacitinib 15 mg was associated with the lowest NNT and CPR among the three Janus kinase inhibitors used in treatment regimens for Japanese patients with moderate-to-severe RA inadequately responsive to csDMARD.

Keywords: Cost per responder; Janus kinase inhibitor; Japan; number needed to treat; rheumatoid arthritis.

MeSH terms

  • Antirheumatic Agents / economics
  • Antirheumatic Agents / therapeutic use
  • Arthritis, Rheumatoid* / drug therapy
  • Cost-Effectiveness Analysis
  • Humans
  • Janus Kinase Inhibitors* / economics
  • Janus Kinase Inhibitors* / therapeutic use
  • Japan
  • Meta-Analysis as Topic
  • Severity of Illness Index
  • Treatment Outcome

Substances

  • Antirheumatic Agents
  • baricitinib
  • Janus Kinase Inhibitors
  • tofacitinib
  • upadacitinib

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