Phase III Program for Arthritis Drug Tabalumab Terminated Based on Efficacy Results
Human immunoglobulin fails to show treatment effect (Feb. 7)
According to a Feb. 7 announcement, the phase III rheumatoid arthritis (RA) program for tabalumab (Eli Lilly), an anti-BAFF (B cell activating factor) monoclonal antibody, is being discontinued because of lack of efficacy. The decision was not based on safety concerns.
In December 2012, the phase III RA registration study FLEX-M was terminated for lack of treatment effect. FLEX-M was investigating tabalumab in patients with moderate-to-severe RA who had shown an inadequate response to methotrexate therapy.
Based on the FLEX-M findings, an interim futility analysis was conducted of the FLEX-V study, which was investigating tabalumab for the treatment of patients with moderate-to-severe RA who had shown an inadequate response to one or more tumor necrosis factor (TNF) inhibitors.
Based on the outcomes of these separate interim futility analyses, Eli Lilly, the drug’s developer, has decided to discontinue development of tabalumab in the current RA program. All ongoing phase II and phase III RA studies will be stopped.
BAFF (B cell activating factor) is a cytokine that promotes B cell survival, proliferation, and activation. In the presence of excess BAFF, B cells — including autoreactive B cells — are not appropriately eliminated by the immune system. These cells may contribute to the development of RA by producing autoantibodies and proinflammatory cytokines and by “helping” autoreactive T cells. BAFF exists in both membrane-bound and soluble forms.
Tabalumab is a human immunoglobulin G subclass 4 (IgG4) monoclonal antibody that inhibits both membrane-bound and soluble BAFF.
Source: Eli Lilly and Company; February 7, 2013.