Lilly Receives Complete Response Letter for Rheumatoid Arthritis Drug

The FDA has issued a complete response letter for a new drug application for baricitinib for the treatment of moderate-to-severe rheumatoid arthritis (RA), according to a press release. Eli Lilly and Incyte Corporation submitted baricitinib for approval in January 2016, but the FDA extended the review period for the analysis of additional data.

Baricitinib is an investigational once-daily JAK inhibitor being evaluated in inflammatory and autoimmune conditions. Since JAK cytokines are thought to be involved in numerous inflammatory and autoimmune diseases, an inhibitor is a promising treatment candidate.

In 2009, Lilly and Incyte launched a collaboration agreement to commercialize baricitinib. The drug received regulatory approval for rheumatoid arthritis in the European Union in February 2017, and is still waiting for approval in Japan, according to the release

Included in the new drug application were positive results from a phase 3 clinical trial of baricitinib in patients with moderate-to-severe RA. Two studies included a comparison with other approved RA drugs, such as methotrexate and adalimumab (Humira).

The results of one study showed that patients treated with baricitinib saw significant improvements in joint pain, severity of morning joint stiffness, and tiredness as early as day 3 compared with placebo. These patients also experienced a significant improvement in the duration of morning joint stiffness by day 5. The improvements with baricitinib were found to be significantly greater than adalimumab by day 17 for joint pain, severity of morning joint stiffness by day 19, and tiredness at day 21, suggesting baricitinib was superior to adalimumab.

The clinical trial program explored the use of baricitinib among various patients, including those who are methotrexate-naïve, inadequate responders to methotrexate, and inadequate responders to conventional or biologic synthetic disease modifying anti-rheumatic drugs, according to the release.

However, the FDA deemed there was not enough clinical data to approve the drug. The FDA requests that Lilly and Incyte include additional data about the most appropriate doses of baricitinib. Additional safety information is also required prior to approval, Lilly reported.

While the companies expressed disappointment with the FDA’s decision, they plan to work with the FDA to remedy any issues to obtain approval of bariticinib, according to the release.

"We are disappointed with this action. We remain confident in the benefit/risk of baricitinib as a new treatment option for adults with moderate-to-severe RA," said Christi Shaw, president of Lilly Bio-Medicines. "We will continue to work with the FDA to determine a path forward and ultimately bring baricitinib to patients in the US."