A Review of the Clinical Trial Landscape in Psoriasis: An Update for Clinicians

As our understanding of the pathogenesis of psoriasis has evolved over the past two decades, so has the number of treatment options. The introduction of biologic agents targeting specific cytokines in the interleukin (IL)-23/IL-17 pathway has proven successful in promoting skin clearance among patients. However, their use is often limited owing to cost, parenteral administration, and possible reduced efficacy over time. Topical therapies have also seen limited advancement, with agents such as corticosteroids and vitamin D derivatives remaining the mainstay of treatment, despite side effects limiting their long-term use. New therapeutic agents are needed to improve disease management for patients. In this review, we summarize pipeline and recently approved therapies undergoing clinical trials for psoriasis during a 12-month search period (30 June 2021 to 30 June 2022) using ClinicalTrials.gov. New-generation biologics and oral small molecules in phase II or III development were included, and pivotal data identified through various search modalities (PubMed, conference presentations, etc.) evaluating each drug candidate will be discussed. Topical therapies will also be discussed in line with recent US Food and Drug Administration approvals. As new therapies continue to enter the treatment landscape, long-term data and comparative trials will be needed to better understand their place among existing therapeutic agents.

Systemic treatment of psoriasis: from methotrexate to biologics

Psoriasis is one of the most frequent chronic inflammatory skin diseases and it has been of interest to many scientists for ages. The review presents data on all systemic treatment options, that are to date officially registered in Russian Federation for moderate-to-severe psoriasis. Aspects of the mechanism of action, efficacy and tolerability of both basic drugs (methotrexate, cyclosporine, acitretin) and biologics (infliximab, adalimumab, etanercept, certolizumab pegol, ustekinumab, guselkumab, secukinumab, ixekizumab, netakimab) and small molecules (tofacitinib, apremilast) are considered in detail. Special emphasis is placed on the important nuances of biological therapy: immunogenicity, drugs' survival and switch due to lack of efficacy. Invention of biologics signified a new era of moderate-to-severe psoriasis treatment. It became possible to achieve complete clinical remission more safely, which significantly improved the quality of life of patients. However, due to the unknown etiology of psoriasis, there is still no universal remedy that would allow to cure every patient, this fact makes scientists from all over the world keep conducting numerous clinical trials to find even more effective and safe therapeutic options.

Long-term efficacy and safety of netakimab in patients with moderate-to-severe psoriasis. Results of phase II open-label extension clinical study BCD-085-2-ext

Netakimabis original monoclonal antibody against IL-17. This article outlines the key results of a phase II open-label extension trial of netakimab 80 mg and 120 mg in patients with moderate-to-severe psoriasis.

The main aim of the trial is to estimate efficacy, safety and immunogenicity of long-term treatment with netakimab 80 mg and 120 mg in patients with moderate-to-severe psoriasis.

Materials and methods. The BCD-085-2-ext study is a comparative, open-label phase 2 clinical study of the effi - cacy and safety of netakimab in patients with moderate-to-severe plaque psoriasis who had finished BCD-085-2 (NCT02762994) trial. Main efficacy endpoints includePASI75, PASI90, PASI100, sPGA = 0–1 on week 38 of the trial, long-term PASI75/90/100 retention, efficacy keeping after switch from once every 2 week regimen to once every 4 week regimen. Safety endpoints include adverse events, serious adverse events number and their profile.

Results. 103 patients were included. PASI75 at week 38 was reached by 98.06 %, PASI90 — by 92.23 %, PASI100 — by 59.22 % of patients. There were no cases of serious adverse event, early with drawal due to adverse events and cases of grade 4 toxicity according to CTCAE 4.03. There were no cases of binding antibodies to netakimab during the 38 weeks of the study.

Conclusion. The first Russian original IL-17 inhibitor netakimabis promising modern medicine for moderate-to-severe plaque psoriasis treatment. Netakimabshowed high efficacy, favorable safety profile and low immunogenicity during one year of the treatment.

Netakimab — new IL-17а inhibitor: 12-week results of phase III clinical study BCD-085-7/PLANETA in patients with moderate-tosevere plaque psoriasis

Netakimab, the original monoclonal antibody against IL-17A, is an innovative drug for the treatment of moderate-to-severe plaque psoriasis in patients who have indications for systemic therapy or phototherapy. Netakimab was approved in Russian Federation, registration certificate number ЛП-005439 from 04.04.2019. This article outlines the first 12-week results of a phase III clinical trial in patients with psoriasis.

Materials and methods. The BCD-085-7 study (PLANETA) is a comparative, randomized, double-blind, placebo-controlled phase 3 clinical study of the efficacy and safety of netakimab in patients with moderate-to-severe plaque psoriasis. This review presents the results of the first 12 weeks. The study is ongoing at the moment, the total duration of treatment for each patient is 3 years (154 weeks). Patients were randomized in a ratio of 2:2:1 into one of three arms: group 1 received netakimab subcutaneously at a dose of 120 mg once a week for the first three weeks (induction) and then once every 2 weeks up to week 10, group 2 received netakimab subcutaneously at a dose of 120 mg once a week for the first three weeks (induction) and then once every 4 weeks up to week 10, group 3 received a placebo subcutaneously on day 1 at weeks 0, 1, 2, 4, 6, 8 10. In order to maintain a double-blind design, placebo was administered to patients in group 2 at weeks 4 and 8.

Results. Both netakimab groups showed a significant superiority over placebo (p < 0.001) and the absence of statistically significant differences between the two regimens of therapy (p > 0.05) across all endpoints. PASI 75 at week 12 was reached by 77.65 % of patients using netakimab once every 2 weeks and 83.33 % of patients using netakimab once every 4 weeks (ITT population). The rate of clear and almost clear skin (sPGA 0–1) was reached by 81.18 and 79.76 % of patients using netakimab once every 2 weeks and once every 4 weeks, respectively. The safety assessment showed no statistically significant differences between the groups, the incidence rate of adverse events in netakimab arms was not higher than in the placebo arm. There were no cases of early withdrawal due to adverse events and cases of grade 4 toxicity according to CTCAE 4.03. During the 12 weeks of the study, one serious adverse event was registered in group 2 (pneumonia grade 3), which was recovered without any consequences. The immunogenicity assessment showed binding antibodies formation at week 12 in one patient who received BCD-085 every 2 weeks. Neutralizing antibodies were not detected. Conclusion. Netakimab showed high efficacy in the treatment of psoriasis, more than 80 % of patients achieved PASI 75 and sPGA 0–1 (clear and almost clear skin) by the week 12 of treatment. The drug showed a favorable safety profile and low immunogenicity. Based on the study results the regimen once a week during the first 3 weeks (induction), then once every 4 weeks was chosen for medical use in patients with psoriasis.

Fab Fragment of VHH-Based Antibody Netakimab: Crystal Structure and Modeling Interaction with Cytokine IL-17A

Interleukin 17A (IL-17A) is a proinflammatory cytokine produced by Th17 cells. Antibody BCD-085 (netakimab) against human IL-17A is one of the new inhibitors of this cytokine. In netakimab, the VH domain is replaced by the VHH domain of Lama glama possessing a long complementarity determining region (CDR-H3) in its heavy chain. Here we demonstrate the high affinity of IL-17A to the Fab fragment of netakimab and to its integral part, the VHH domain. We have determined the crystal structure of the Fab fragment of netakimab at 1.9 Å resolution. High variability in the orientation of light and heavy chains of the Fab fragment of netakimab was shown, which is determined by the peculiarity of the structural organization of the CDR-H3. As the high conformational plasticity of the molecule hampers modeling the Fab fragment of netakimab complexed to IL-17A, we have carried out modeling the complex between the antigen and the integral part of the Fab fragment, the VHH domain. We explain the high netakimab Fab fragment affinity for IL-17A by a large number of protein–protein contacts due to additional interactions between CDR-H3 and the cytokine dimer.