Efficacy and safety of biological agents to treat patients with palmoplantar pustulosis: A systematic scoping review

Palmoplantar pustulosis (PPP), a chronic, recurrent pustular dermatosis associated with erythema, scales, and sterile pustules on the palms and soles, is commonly encountered in dermatology clinics. Whether PPP is a variant of psoriasis or a distinct condition is still debated. Although biological agents have been successfully used to treat moderate-to-severe psoriasis, existing literature on PPP is limited to case reports or small case series. The lack of well-documented clinical studies makes it difficult to select the ideal treatment for this condition. This review aims to discuss the efficacy and safety of biological agents in PPP treatment based on randomized controlled trials with the hope of inspiring dermatologist clinicians to propose new therapeutic approaches.This review aims to obtain high-level evidence to assess the efficacy and safety of biological agents in the treatment of patients with PPP.We searched the PubMed, Embase, and Cochrane databases up to May 18, 2023, for high-quality randomized controlled trials that reported at least one adverse event after PPP treatment with biological agents in patients > 18 years of age. RevMan 5.3 software was used for the meta-analysis.Nine trials involving 799 participants were included in the analysis. We used ppPASI 75 as the primary efficacy measure. Anti-IL-23 and anti-IL-17A agents afforded 4.14-fold and 1.95-fold better outcomes than placebo treatment at weeks 16 and 12, respectively (P-value = 0.009, RR = 4.14, 95% confidence interval [CI; 1.43-11.98]; P-value = 0.02, RR = 1.95, 95% CI [1.11-3.42]). Moreover, anti-IL-23 agents at a dose of 100 mg were more effective than at 200 mg, indicating that 100 mg may be the best dose for anti-IL-23 agents. Next, we investigated the safety of biological agents for PPP treatment. The incidence of total adverse events (AEs) was 1.25 times higher for biological agents than for controls, indicating a good safety profile (RR = 1.25, P-value ＜ 0.00001, 95% CI [1.13, 1.37]). Additionally, we divided the common AEs into 16 categories and found that anti-IL-23 agents were more likely to induce infections. In conclusion, we evaluated safety and efficacy in a comprehensive comparison and found that anti-IL-23 agents conferred good clinical efficacy with a low incidence of AEs and could be recommended with caution.Only a few relevant, high-quality, randomized controlled trials were included in the study.This study showed that biological agents can be used to treat patients with PPP with good efficacy; however, AEs cannot be ignored. Multi-center, high-quality clinical studies with large sample sizes are needed to further evaluate the effects and safety of biological agents in PPP treatment.