Branebrutinib makes no difference in RA management

A phase 2a trial of rheumatoid arthritis (RA) has shown no significant difference between the investigational branebrutinib and placebo in terms of clinical efficacy, despite the drug having a favourable safety profile.

The study included 85 adults (mean age 49.1 years, 74 percent female, 94 percent White) who met the 2010 American College of Rheumatology (ACR)–European Alliance of Associations for Rheumatology criteria for RA, had disease duration of <4 years, and had inadequate response to methotrexate.

The patients were randomly assigned to receive branebrutinib 9 mg (n=64) or placebo (n=21), administered once daily for 12 weeks. This was followed by an additional 12-week open-label treatment with abatacept.

The primary endpoint of the proportion of patients who had achieved a 50-percent improvement in the ACR response criteria (ACR50) at week 12 was not met, being only 19 percent with branebrutinib vs 33 percent with placebo (p=0.16).

Adverse events occurred in 47 percent of patients in the branebrutinib group and in 38 percent of those in the placebo group. None of the patients in either treatment group experienced serious adverse events or deaths.

Branebrutinib was an oral, highly selective, and irreversible Bruton’s tyrosine kinase inhibitor. The rationale for its use in RA was centred on its potential role in B-cell activation, autoantibody production, and proinflammatory cytokine release, all of which are implicated in RA disease activity and progression.