Real-World Bimekizumab Outcomes in Plaque Psoriasis

Key Takeaways

• Most patients showed marked skin improvement by week 16, and complete clearance was reported in about two-thirds of the cohort.
• Responses appeared early, and week-16 PASI 90 rates were numerically higher in biologic-naïve patients than in biologic-experienced patients.
• Quality-of-life scores improved substantially, candidiasis was the most common adverse event, and no serious adverse events or treatment discontinuations were recorded.

In a single-centre retrospective study from routine practice at Istanbul University-Cerrahpasa, 71% of 86 adults with moderate-to-severe plaque psoriasis reached PASI 90 by week 16 with bimekizumab. The cohort reflected short-term use over 16 weeks in a real-world dermatology setting rather than a trial population. Early responses, better dermatology-specific quality of life, and improvement in several difficult-to-treat sites were also observed during follow-up.

The single-centre retrospective observational study was conducted in routine practice at Istanbul University-Cerrahpasa, Department of Dermatology and Venereology, from 1 January 2025 to 30 April 2025. Eligible adults were aged 18 years or older and had chronic plaque psoriasis diagnosed at least 6 months earlier. Eligibility also required PASI 10 or higher, body surface area 10% or higher, and candidacy for systemic therapy. Patients received bimekizumab 320 mg subcutaneously every 4 weeks for 16 weeks, with assessments at baseline and weeks 4, 8, 12, and 16. Primary outcomes were week-16 PASI 90 and PASI 100; secondary outcomes included PASI 50 and PASI 75, DLQI, time to response, special-site outcomes, and adverse events. The cohort had a mean age of 44.4 years, 53% women, a mean BMI of 33.1 kg/m2, baseline mean PASI 26.8, and 58% prior biologic exposure.

By week 16, 66% of patients achieved complete clearance alongside the reported week-16 PASI 90 rate. By week 4, 50% had already reached PASI 90, and the median time to PASI 75 was 4.2 weeks with a 95% CI of 3.8 to 4.6 weeks. Week-16 PASI 90 was 75% in biologic-naïve patients and 60% in biologic-experienced patients, with P = 0.08. Among previously treated patients, those with prior anti-IL-23 failure had lower PASI 90 rates than those with prior anti-TNF or anti-IL-17 failure. The results reflected a rapid response pattern across the 16-week follow-up.

By week 16, complete clearance was reported in 71% of 42 patients with scalp psoriasis, 63% of 35 with nail psoriasis, and 75% of 20 with genital psoriasis. Mean DLQI fell from 15.8 at baseline to 3.2 at week 16, for a mean change of -12.6 with a 95% CI of -13.9 to -11.3. In addition, 65% of patients reached a DLQI score of 0 or 1 by week 16. These site-specific responses were accompanied by lower dermatology-related quality-of-life burden over 16 weeks.

Adverse events occurred in 33% of the cohort, and candidiasis was the most common event at 17%. Cases of candidiasis were mild or moderate and resolved with topical antifungal therapy. Other events included upper respiratory tract infection, nasopharyngitis, injection-site reaction, and fatigue. No serious adverse events, inflammatory bowel disease, malignancies, or treatment discontinuations were observed.

These findings remain bounded by the author-stated limitations, including retrospective single-arm design, no direct comparator, short follow-up, absent pharmacokinetic or immunogenicity data, and clinically judged special-site assessment.