The Value of Indirect Comparisons of Systemic Biologics for Psoriasis: Interpretation of Efficacy Findings

INTRODUCTION: It can be challenging for dermatologists to keep abreast of the growing evidence from published indirect comparisons (ICs) of treatments for psoriasis. The objective of this analysis was to summarise comparative clinical efficacy and safety findings from ICs of systemic biologics for the treatment of moderate-to-severe psoriasis and to identify factors potentially affecting efficacy outcomes and their possible implications for clinical decision making.

METHODS: An umbrella review of short- and long-term efficacy and safety findings from 26 ICs visually compared 90% improvement in Psoriasis Area Severity Index (PASI90) treatment rankings and three safety outcome rankings side by side. Pearson's correlation coefficients measured the strength of the association between each pair of ICs on the basis of identified factors that could potentially affect efficacy findings.

RESULTS: Some consistency in short-term PASI90 efficacy rankings was observed for certain drugs, although rankings for most drugs varied by IC. Factors potentially affecting efficacy outcomes included the use of different methodologies for head-to-head comparison and statistical analyses, and variation in drugs and classes included treatment dosing and duration, outcome definitions and effect measures reported between ICs. Considerable variation in these factors was found across all 26 ICs. Comparative safety information of value to physicians was limited.

CONCLUSIONS: Substantial differences were identified between ICs in factors that could potentially affect efficacy outcomes. Treatment rankings must be interpreted alongside actual differences in IC outcomes to allow conclusions on clinical relevance. Drugs within a class cannot be considered of equal efficacy: therapies should be considered individually rather than by class.