Efficacy and safety of tofacitinib in US and non-US rheumatoid arthritis patients: pooled analyses of phase II and III.

OBJECTIVES

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis. This post-hoc pooled analysis assessed commonalities and differences in tofacitinib efficacy and safety for US versus rest of the world (ROW) populations.

METHODS

Pooled phase (P) III data from patients receiving tofacitinib 5 or 10 mg twice daily (BID) or placebo were assessed for efficacy at Month 3 and for safety outcomes over 12 months. For adverse events of special interest, data on tofacitinib 5 or 10 mg BID or placebo were pooled from six PII and five PIII randomised studies.

RESULTS

PIII data were available for 664 vs. 2447 and PII/PIII data for 943 vs. 3567 US vs. ROW patients, respectively. The US population had a higher proportion of Caucasians (81.5% vs. 54.4%), lower proportion of Asians (1.0% vs. 34.6%), and higher mean body weight (85.7 vs. 66.2 kg) and body mass index (31.5 vs. 25.6 kg/m2) compared with ROW. At Month 3, PIII efficacy was similar between US and ROW as assessed by ACR 20/50/70 response rates, remission rates (DAS 28-4[ESR]<2.6), and HAQ-DI scores. Diarrhoea, peripheral oedema, and upper respiratory tract infection occurred in >5% of PIII patients in the US population. Incidence rates for adverse events of special interest were similar between the US and ROW PII/PIII populations.

CONCLUSIONS

Patients in the US achieved similar efficacy and safety with tofacitinib 5 and 10 mg BID compared with patients in ROW.