Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits IL-17F in addition to IL-17A, both members of the IL-17 family of proinflammatory cytokines. Bimekizumab provides rapid and long-term response in patients with moderate-to-severe plaque psoriasis. At the European Academy of Dermatology and Venereology (EADV) 2023 Congress, three posters were presented reporting 3-year results from the Phase III/IIIb clinical trials of bimekizumab in plaque psoriasis.
The first poster focused on the subgroup of patients in a pooled analysis who achieved a 90% or 100% improvement from baseline Psoriasis Area and Severity Index (PASI 90/100) or Investigator’s Global Assessment (IGA) of 0 or 1 (IGA 0/1) at Week 16, and showed that these responses could be maintained through to 3 years of treatment. The second poster focused on another subgroup of patients in the pooled analysis, who had scalp, nail, or palmoplantar involvement at baseline, and reported the proportion of patients achieving clearance in these high-impact areas over 3 years. High levels of complete scalp and palmoplantar clearance were shown after 16 weeks, which were sustained through to Year 3. Levels of complete nail clearance increased through the end of Year 1, reflective of the longer time required for nail growth, and were then sustained to the end of Year 3. The third poster presented data from the BE READY randomised withdrawal trial. The analysis focused on patients achieving PASI 90 at Week 16, who were then re-randomised to placebo. Around one-third of these patients retained PASI 75 until Week 56. For the two-thirds of patients who dropped below this level, restarting bimekizumab 320 mg every 4 weeks as ‘escape’ treatment led the majority to return to PASI 90 after 12 weeks. Both groups of patients could enter the subsequent open-label extension, and high responses were sustained through 3 years, showing that treatment interruption did not meaningfully impact long-term disease control.
The results presented in these posters show that high levels of response can be achieved with bimekizumab through 3 years of treatment. Initial responses were well-maintained; patients with scalp, nail, or palmoplantar involvement showed clearance in these high-impact areas; and long-term response was not affected by withdrawal and re-treatment.