Treatment Outcome Of Tofacitinib Dose Reduction To 5 Mg Bid Vs Remaining On 10 Mg Bid In Patients With Uc Who Were In Stable Remission On 10 Mg Bid: 6-Month Data From The Double-Blind, Randomized Riveting Study

INTRODUCTION: Tofacitinib is an oral, small molecule JAK inhibitor for the treatment of UC. Efficacy and safety of tofacitinib were evaluated in Phase 3 trials, incl. maintenance treatment with tofacitinib 5 and 10 mg BID (1,2). We present primary completion analysis of the RIVETING study (NCT03281304), designed to evaluate the efficacy and safety of dose reduction to 5 mg BID vs remaining on 10 mg BID in patients (pts) with UC in stable remission on tofacitinib 10 mg BID maintenance therapy. METHODS: RIVETING is an ongoing, double-blind, randomized, parallel-group study. Eligible pts had received tofacitinib 10 mg BID for ≥2 consecutive yrs in an open-label, long-term extension study (NCT01470612), and been in stable remission on this dose for ≥6 months (mo) prior to enrollment. The aim of RIVETING was to estimate treatment difference between tofacitinib 5 and 10 mg BID doses. This primary analysis was conducted when all pts completed their Mo6 study visit. Efficacy was assessed at Mo6; safety was assessed throughout. RESULTS: In total, 140 pts were randomized (1:1) to tofacitinib 5 or 10 mg BID. 77.1% and 90.0% of pts were in remission based on modified Mayo score at Mo6 (primary endpoint) in the 5 and 10 mg BID groups, respectively (adjusted difference 12.9%; 95% CI 0.5, 25.0); when analyzed by subgroup (baseline endoscopic subscore; prior TNFi treatment failure), differences ranged from 9.5% to 21.1%. Consistent dose-group differences were seen for the secondary endpoints of remission and clinical response, according to total Mayo score, and mucosal healing. Rates of AEs and SAEs were similar across dose groups. AEs of special interest included (Table): serious infections (5 mg BID, n = 2); herpes zoster (5 mg BID, n = 1; 10 mg BID, n = 3; all non-serious); pulmonary embolism (10 mg BID, n = 1). There were no cases of deep vein thrombosis or death. CONCLUSION: These 6-mo data from RIVETING showed that most pts in stable remission on tofacitinib 10 mg BID maintenance therapy, maintained remission after dose reduction to 5 mg BID. Differences between dose groups were 11.4%–12.9% for various efficacy endpoints, favoring the 10 mg BID group. For pts who reduced dose to 5 mg BID, pts with baseline endoscopic subscore 0 and those without prior TNFi failure were more likely to maintain remission vs pts with subscore 1 and pts with prior TNFi failure, respectively. No new safety risks were identified in this limited dataset.Table 1