Real-World Experience of Bimekizumab in an Elderly Patients Cohort with Plaque-Type Psoriasis: A 24-Week Retrospective Study

Psoriasis significantly impacts the quality of life, particularly in elderly patients who may have additional comorbidities.¹ Conventional treatments often pose challenges due to the increased risk of adverse events (AEs) in this population. Bimekizumab (BKZ), a monoclonal antibody targeting both interleukin (IL)-17A and IL-17F, has shown promising results in clinical trials.² However, real-world data concerning its use in elderly patients, remains limited.

This 24-week retrospective study involving two Italian dermatological centers (Udine and Brescia) aims to bridge this knowledge gap by evaluating the efficacy and safety of BKZ in elderly patients with moderate-to-severe [Psoriasis Area and Severity Index (PASI) >10] plaque psoriasis. Consecutive psoriatic patients aged ≥65 year-old and treated with BKZ (standard dosing regimen)² were considered; we excluded patients lacking 24-week follow-up or taking concomitant anti-psoriatic therapies (systemic/topical). Demographic/medical information was collected (gender, age, BMI, date of diagnosis of psoriasis, comorbidities and previous/current systemic treatments). Treatment efficacy was evaluated using PASI score at baseline (week 0), Week-4, Week-16 and Week-24; percentage improvement of 75%, 90% and 100% compared to baseline (respectively PASI75, 90 and 100) was also considered at each time point. Safety profile was assessed by monitoring AEs.

A total of 15 elderly patients were enrolled in the analysis (M/F: 10/5; mean age: 71.3 ± 4.3 years (min. 66 years; max 81 years); and mean BMI: 26.0 ± 2.9); mean psoriasis duration was 16.1 ± 8.8 years. Fourteen patients (93.3%) had previously been treated with at least one conventional therapy, while eight (53.3%) and five (33.3%) patients were failure to one and three or more biologics, respectively. The most frequent comorbidity was arterial hypertension, followed by diabetes and chronic kidney disease. At baseline, the mean PASI was 15.3 ± 10.0, eight patients (53.3%) had involvement of one or more difficult-to-treat cutaneous domain (ie, genitalia, scalp, and palms/soles), and four patients (28.6%) had nail psoriasis. Table 1 summarizes all baseline demographic/clinical characteristics.

Table 1 Demographic and Clinical Data of Study Population

During the follow-up (Figure 1), mean PASI decreased from 15.3 ± 10.0 (baseline) to 3.7 ± 3.4 at Week 4 and to 0.8 ±1.2 at Week-16, whereas a slight increase (1.5 ± 4.0) was observed at Week-24. In terms of percentage improvement, at Week-4 we found PASI75 and PASI100 in 80.0% and 20.0% of patients, respectively, while at Week 16, 92.9%, 78.6% and 57.1% of patients respectively reached PASI75, PASI90 and PASI100, with this positive trend continuing at week 24 (PASI75, PASI90, PASI100 observed in 92.9%, 78.6% and 64.3% of patients, respectively). BKZ was overall well tolerated, with two patients (13.3%) discontinuing treatment due to acute urticaria and oral candidiasis at Week-8 and 24, respectively (both healed after BKZ withdrawal and specific treatment); no other AEs were reported.

Figure 1 PASI responses at follow-up visits. Psoriasis Area Severity Index (PASI) 75, 90 and 100 responses after 4, 16, and 24 weeks of Bimekizumab treatment.

This 24-week real-life study suggests that BKZ is an effective treatment for moderate-to-severe plaque psoriasis in elderly patients, even in multi-failure cases. Complete (PASI100) or nearly complete (PASI90) responses after 6 months were greater than Secukinumab^3,4 and slightly lower than Ixekizumab^5,6 in the same subset of patients in real life, yet more than half of our instances were resistant to such agents. In another study evaluating biologic therapies in the elderly⁷ Brodalumab achieved slightly superior PASI75 and PASI90 responses than PASI75 and PASI90 responses in our study at week 24. However, this result must be taken with caution since patients’ characteristics of the group under Brodalumab treatment were not reported, preventing us from making any comparison between the frequencies of patients’ features in the two groups that might impair treatment responses. Furthermore, PASI100 responses were not reported.

Considering anti-IL-23 therapies, patients treated with BKZ in our study achieved PASI90 and PASI100 responses in higher proportions than patients from a study evaluating the safety and efficacy of Tildrakizumab⁸ and from another study evaluating the safety and efficacy of the three currently approved IL-23p19-inhibitors.⁹ Interestingly, we also found slightly lower responses after 24 weeks compared to another real-life analysis not considering specifically the elderly,¹⁰ consistently with other studies evaluating the impact of aging on clinical responses to anti-psoriatic biologics.¹¹ This finding might result from a lower number and decreased activity of regulatory T cells in elderly patients that make their psoriasis more resistant to treatments.¹²

Other studies have evaluated the efficacy of BKZ in a real-world setting. Rimke et al¹³ and Rompoti et al¹⁴ reported similar PASI75, 90 and 100 responses to what was observed in our study, while Hagino et al¹⁵ reported lower proportions of patients achieving PASI75, 90 and 100, even though we focused on an older population. An explanation to these results might be found in the baseline characteristics of patients included in each study. For instance, while 13.3%, 6.7% and 26.7% of our patients presented respectively scalp, palmoplantar and nail involvement, these same characteristics were present respectively in 41.0%, 18% and 36.1% of patients in Rompoti et al, while scalp and nail involvement were present in 91.7% and 66.7% of patients respectively in Hagino et al. These factors might represent a predictor of worse response regardless of age.

Finally, despite the complex health profiles typical of elderly populations, BKZ demonstrated a favorable safety profile, with only two patients discontinuing treatment due to minor AEs, with a rate lower than what observed in a real-life analysis including both elderly and non-elderly.¹⁰ Limitations to our study are the small sample size and the relatively short observation period. Furthermore, we did not collect patients’ non-dermatological medication use, which might have played a role in the development of adverse events. Future analyses with larger cohorts and longer follow-up are needed to validate our findings and to possibly identify patients’ characteristics that may better predict treatment responses and the likelihood of adverse events’ occurrence.