FDA Approves Bimekizumab-bkzx (Bimzelx) for 3 New Rheumatic Indications

In September 2024, the U.S. Food & Drug Administration (FDA) approved bimekizumab-bkzx (Bimzelx) for three new indications in adults: psoriatic arthritis (PsA), non-radiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS).¹

Bimekizumab-bkzx (Bimzelx) is a humanized interleukin (IL) 17A and F antagonist injection initially approved by the FDA on Oct. 17, 2023, for the treatment of adults with moderate to severe plaque psoriasis who are candidates for systemic therapy or phototherapy.² As previously reported, the FDA accepted these supplemental biologics license applications in February 2024.^3,4

The recommended, FDA-approved dosing for adults with these new indications is 160 mg of subcutaneous bimekizumab-bkzx every four weeks.

PsA

The approval of bimekizumab-bkzx in adults with PsA was supported by data from the phase 3 BE OPTIMAL and BE COMPLETE studies. These two trials were double blind and placebo controlled.^5,6

In BE OPTIMAL, patients (N=852) who had not previously received biologic disease-modifying anti-rheumatic drugs (bDMARDs) were evaluated. In BE COMPLETE, patients (N=400) who were intolerant of or had an inadequate response to one or two tumor necrosis factor (TNF) alpha inhibitors were evaluated. The primary end point of both studies was a ACR50 response at week 16 compared with placebo. In both studies, this end point was met and was clinically and statistically significant (P<0.0001). Uniform study results were seen in both biologic-naive patients and those for whom TNF inhibitors had been inadequate.

The clinical response targets were reached at week 16 and maintained through week 52 in BE OPTIMAL and BE COMPLETE, as well as an open-label extension study, which used ACR50 as the primary end point.^4,5,7,8

Additionally, all ranked secondary end points were met. These end points included Psoriasis Area and Severity Index 90 (PASI90) response rates, minimal disease activity and PASI100 response rates (e.g., complete skin clearance). These secondary end points were maintained through week 52.

The most common adverse reactions in these clinical trials were diarrhea, headache, oral candidiasis, upper respiratory tract infection and urinary tract infection.

nr-axSpA & AS

The approval of bimekizumab-bkzx for adults with nr-axSpA and objective inflammation signs was supported by data from BE MOBILE 1 (n=254). Meanwhile, the agent’s approval for |adults with active AS was supported by data from BE MOBILE 2 (n=332). Both of these clinical trials were double blind and placebo controlled.^9,10

In these studies, patients taking bimekizumab achieved an Assessment of SpondyloArthritis International Society 40 (ASAS40) response at week 16, meeting the study’s primary end point (P<0.001) and all secondary end points. Uniform ASAS40 results were seen in patients who were TNF inhibitor naive and those for whom TNF inhibitors were inadequate. The clinical responses achieved at week 16 were maintained through week 52 in both patients with nr-axSpA and AS, as assessed by ASAS40 and secondary and other end points.