AbbVie's Potential Competitor to Xeljanz for RA Meets Endpoints

Upadacitinib, the investigational oral JAK1-selective inhibitor to treat patients with moderate to severe rheumatoid arthritis (RA), met all primary and key secondary endpoints in its phase 3 clinical, the pharmaceutical company AbbVie has announced.

If approved, upadacitinib would be a competitor to Xeljanz, which is currently the only US-approved JAK inhibitor for RA, a painful chronic inflammatory disease marked by painful joint swelling and deformity. JAK inhibitors are indicated for patients who fail to respond to disease-modifying antirheumatic drugs, (DMARDs). The FDA recently turned down an application for a JAK inhibitor sponsored by Eli Lilly.

In its statement, AbbVie said that results of a 12-week clinical trial showed that patients taking both doses of upadacitinib (15 mg and 30 mg) met the study’s primary endpoint of low disease activity and ACR20, a standard response criteria of the American College of Rheumatology that indicates 20% improvement in tender or swollen joint count and 20% improvement in 3 of the other 5 criteria, which are: acute phase reactant, patient assessment, pain scale, physician assessment, and functional questionnaire.

The key secondary endpoints were achieved, which included ACR50 and ACR70, stricter standards under the college’s criteria, as well as clinical remission. Results at 12 weeks showed that 64% of those taking the 15 mg dose and 66% taking the 30 mg dose achieved ACR20, compared with 36% taking placebo. Those taking the study drug achieved ACR50 responses of 38% (15 mg) and 43% (30 mg), compared with 6% taking placebo.

Low disease activity was reported in 48% taking either dose of updacitinib compared with 17% of placebo, and clinical remission was reported by 31% of those taking 15 mg and 28% of those taking 30 mg compared with 10% on placebo.

“We are excited by these promising results for updacitinib,” AbbVie’s chief scientific officer Michael Severino, MD, said in a statement. “We are especially encouraged by the results on the more stringent measures of efficacy, such as ACR70, low disease activity and clinical remission. We look forward to seeing the full results from our phase 3 program.”

The company said it will present full results at a future scientific meeting.