Tildrakizumab in real‐life shows good efficacy in moderate‐to‐severe psoriasis regardless of previous use of biologic drugs and joint involvement

Dear Editor, Tildrakizumab was approved in Europe in 2018 for the treatment of moderate-to-severe psoriasis, and its blockade of the p19 subunit of the IL23 provides efficacy and long-term maintenance, of treatment response, with a favorable safety profile in several phase III trials. Although registration studies and recent meta-analyses show a lower efficacy of tildrakizumab compared to other IL23 inhibitors, real-life evidence appears more promising, even in the management of obese patients and with the involvement of difficult sites. We conducted a retrospective study at the dermatology clinic of the University Hospital in Turin on patients treated with tildrakizumab over the last 2 years, with a maximum follow-up of 52 weeks, evaluating the response in terms of PASI (psoriasis-area-severity-index), absolute (mean and <3) and relative (PASI75, 90, and 100) and the impact on quality of life (via DLQI dermatology-life-quality-index). Among 1635 psoriatic patients on biologics attending our clinic, 129 received tildrakizumab. 120 patients reached 16 weeks of treatment, 102, 80, and 42 reached weeks 28, 40, and 52, respectively. Characteristics of general populations were summarized in table 1. Mean initial PASI was 9.7 (±3.4) and DLQI was 26.53 (±2.47). Mean PASI fell to 2.58 (±2.16) at 16 weeks, 1.76 (±1.83), 1.61 (±1.88), and 1.25 (±1.79) at weeks 28, 40, and 52, respectively. DLQI fell to 2.52 at week 40 (±4.62) and 2.58 (±5.17) at week 52, with a DLQI 0/1 reached by 46 patients (58%) and 34 (62%) at week 40 and 52. The percentage of patients achieving PASI100 progressively increased at various time points from 20% at week 16 to 48% at week 52. Similar observations are possible for PASI90 which increased from 28% to 53% in the same time interval, PASI75 from 55% to 76%, and PASI<3 from 64% to 71%. In Figure 1, it can be observed that for PASI100 at week 52 a plateau is not yet. Relative to previous use of biological drugs, bio-naive patients did not show a significant advantage over bio-experienced patients with tildrakizumab. Similar observations can be made in the case of joint involvement or not. Involvement of difficult sites results in significant differences in the attainment of PASI100 at weeks 16, 28, and 40 (11% vs. 30% p = 0.034, 16% vs. 42% p = 0.042, and 21% vs. 55%, p = 0.01), PASI75 and 90 and mean PASI at week 40 (59% vs. 95% p = 0.004, 35% vs. 75% p = 0.01, and 2.1 vs. 0.75 p = 0.005). Tildrakizumab showed to be effective and safe in the treatment of moderate–severe psoriasis in line with previous real-life studies and clinical trials, it does not appear to be influenced by the arthritic component or previous treatment failures, unlike risankizumab which showed less efficacy. Overall, our population showed less efficacy in achieving PASI75, 90, and <3 than was reported by Caldarola et al. at week 28 (81.40% vs. 75%, 64.4% vs. 48%, and 79.7% vs. 75%, respectively), these differences are also found concerning other reallife trials. The achievement of relative PASIs is in line with the results of the registration studies resurface-1 and -2 which showed the attainment of PASI75, 90, and 100 at 28 weeks in 80%, 52%, and 24%, 73%, 55%, and 22% of patients, respectively. Although the Galluzzo et al. study shows good efficacy in the management of difficult sites, in our population the involvement of these sites limits the achievement of relative PASI 90 and 100. Limit of our study is the low number of patients at 52 weeks and the low mean baseline PASI. Despite clinical trials showed an apparently lower efficacy of tildrakizumab compared to other IL23 inhibitors, the low influence of comorbidities and prior therapeutic experience and the progressive