Pain Reduction in Rheumatoid Arthritis Patients Who Use Opioids: A Post Hoc Analysis of Phase 3 Trials of Baricitinib

OBJECTIVE: Pain reduction with baricitinib was assessed in patients with rheumatoid arthritis (RA) who either used opioids or did not use opioids during three randomized, double‐blind phase 3 trials. METHODS: Analysis populations were as follows: i) baricitinib 4 mg once daily versus placebo groups integrated from RA‐BEAM (NCT01710358) for patients with inadequate response (IR) to methotrexate, RA‐BUILD (NCT01721057) with IR to conventional disease‐modifying antirheumatic drugs, and RA‐BEACON (NCT01721044) with IR to at least one tumor necrosis factor inhibitors; ii) baricitinib 2 mg versus placebo from RA‐BUILD and RA‐BEACON; and iii) adalimumab 40 mg every other week versus placebo from RA‐BEAM. Pain was measured by the Patient Assessment of Pain Visual Analog Scale. Analysis of covariance modeling assessed differences in pain reduction between treatments at each time point through Week 24, with an interaction term to test heterogeneous treatment effects across opioid users and nonusers. RESULTS: Baricitinib 4 mg had greater pain reduction versus placebo in opioid users and nonusers (P < 0.05) at all time points starting from Week 1; the pain reduction was similar between opioid users and nonusers. Baricitinib 2 mg had greater pain reduction versus placebo in opioid users and nonusers starting at Week 4. A significant difference in pain reduction was not observed for adalimumab versus placebo in the opioid users but was observed in nonusers at all time points. CONCLUSION: Pain reduction was observed and was similar between opioid users and nonusers with baricitinib 2 mg and 4 mg but not adalimumab in this post hoc analysis.