Baricitinib Data Suggests Long-Term Safety for Rheumatoid Arthritis

In a pooled analysis of baricitinib in patients with rheumatoid arthritis (RA), the rate of major adverse cardiovascular events (MACE) was comparable across all datasets and did not increase with extended exposure.

The results on baricitinib, an oral selective inhibitor of Janus kinase 1 and 2, were presented at the 2017 American College of Rheumatology/Association of Rheumatology Health Professionals

Annual Meeting.

The researchers completed a pooled analysis of 8 completed baricitinib clinical trials — one phase 1b, three phase 2 and four phase 3 trials as well as one long-term extension study with data up to Sept. 1, 2016. A combined analysis, known as All BARI RA, included all patients exposed to any baricitinib dose. The placebo comparisons were based on 6 studies in which patients were on 4-mg of baricitinib once daily or placebo. The researchers evaluated dose response in 4 trials that included a once daily 2-mg or 4-mg dose of baricitinib and data from the long-term extension study.

An independent panel blindly assessed rates of MACE, a composite of myocardial infarction, stroke and cardiovascular death, for the phase 3 studies and the long-term extension study. The investigators also assessed rates of deep vein thrombosis (DVT) and pulmonary embolism (PE).

In all, 2723 patients were on baricitinib for more than 1 year, and 1867 patients took it for more than 2 years.

When the researchers analyzed the 6 placebo-controlled studies, they found that the placebo group reported 2 cases of MACE and the 4-mg baricitinib group reported 3 cases. No patients had DVTs/PEs in the placebo group, whereas 5 patients had these complications in the baricitinib group, 2 of which were serious.

The data from the long-term extension study showed similar incidence rates for MACE and DVT/PE for both doses. Incidence rates were 0.51 per 100 person year for MACE and 0.46 for DVT/PE in the All BARI RA group.

“For MACE, IR were similar across analysis sets and did not increase with prolonged exposure,” the authors wrote. “For DVT/PE, events were reported for BARI 4 mg but not PBO; IR were similar between doses, consistent over time and comparable to published rates in RA.”