Pfizer has reported data from its phase III trial of its oral JAK inhibitor tofacitinib, which underwent a name change from tasocitinib. The drug hit its primary endpoint for statistical significance among patients with rheumatoid arthritis. The experimental therapy, one of Pfizer's biggest late-stage prospects, was shown to improve symptoms of RA. Full data will be forthcoming.

The drug targets the intracellular signaling pathways—rather than extracellular targets—that operate as hubs in the inflammatory cytokine network. Analysts have been awaiting the results of its potential for RA treatment as well as for a full slate of other inflammatory conditions.