Lilly reports first pivotal data for Xeljanz rival in arthritis

Eli Lilly and Incyte's JAK 1/2 inhibitor baricitinib has passed its first phase III test, showing a significant improvement over placebo in patients with rheumatoid arthritis (RA).

Positive results from the first of five late-stage trials of baricitinib put the drug on track for a possible filing in late 2015/early 2016 as the two companies try to catch up with Pfizer, whose JAK inhibitor Xeljanz (tofacitinib) was first approved for RA in 2012.

The study - called RA-BEACON - involved 527 patients who had previously failed at least one anti-TNF drug, the standard biologic therapy for RA and were randomised to treatment with one of two daily doses of the JAK inhibitor or placebo.

Lilly is not giving too much away just yet, but said the drug met its primary objective of a significant increase in the ACR20 response - a 20% improvement in RA symptoms - compared to placebo.

"People with rheumatoid arthritis who have had an inadequate response to TNF inhibitors are generally considered to be the least responsive to subsequent treatments," commented David Ricks, who head Lilly's biomedicines group.

"These results give us further confidence in the potential for baricitinib to be a meaningful treatment option for those suffering from this debilitating condition," he added.

Lilly's phase III programme for baricitinib has studies looking at all the different phases of RA treatment, including early disease where patients are randomised to get baricitinib alone, baricitinib plus methotrexate or just methotrexate alone.

The company has two studies in TNF-naïve but methotrexate or DMARD inadequate responders and also has a much-anticipated head-to-head comparison with AbbVie's big-selling TNF inhibitor Humira (adalimumab), the top biologic therapy for RA.

Despite coming to market later than Xeljanz, Lilly believes its drug has the potential to mount strong competition to Pfizer's drug, in particular because it can be given once-daily rather than twice-daily but also because it may have a clear safety profile.

Baricitinib was licensed by Lilly from Incyte in 2009 in a deal which included $90m upfront and up to $665m in milestone payments plus royalties.

Meanwhile, the positive data for baricitinib in RA is a boost for Lilly's anti-inflammatory portfolio, which suffered a casualty in October when tabalumab was dropped from development.  The BLyS/BAFF-targeting antibody had failed to show activity in phase III trials in both RA and lupus.