Efficacy of Intralesional Purified Protein Derivative for Cutaneous Warts: A Meta-analysis

Introduction. Intralesional purified protein derivative (PPD) is an affordable therapeutic option that has been studied for cutaneous warts. However, the lack of good evidence precludes its widespread use.

Objective. To determine the efficacy and safety of intralesional PPD in the treatment of cutaneous warts. Methods. A systematic search for controlled clinical trials comparing intralesional PPD and placebo or any conventional therapy was conducted using electronic databases. The included studies were assessed for risk of bias, and data such as clearance rate of target and distant lesions, recurrence rate, and adverse events were extracted. Analysis was done through RevMan v5.3

Results. Four controlled clinical trials composed of 205 patients were included. All of the studies compared intralesional PPD to placebo as comparator. Intralesional PPD had a significantly higher clearance rate of target wart (RR=0.43[0.22,0.84], P=0.01) and a significantly higher clearance rate of distant lesions (RR=0.59[0.41,0.85], P=0.005) as compared to placebo. However, there was no significant difference in the recurrence rate (RR=0 [-0.07,0.07], P=0.98). Adverse events reported were only considered minor.

Conclusion. Intralesional PPD is an effective and safe treatment option for cutaneous warts. However, more well-structured RCTs with longer follow-up period and those comparing it with conventional treatment are needed to further support its use.