Multiplex PCR Test Differentiates Four Causes of Ulcerative Skin Lesions

Vesicular and pustular skin lesions can stem from multiple viral pathogens, complicating timely diagnosis and management. Sequential single-pathogen testing can miss infections when the causative agent is not initially targeted. Laboratories therefore need consolidated workflows that broaden etiologic coverage while maintaining analytical rigor. A newly authorized multiplex real-time PCR test now enables simultaneous detection and differentiation of HSV-1, HSV-2, VZV, and MPXV in a single assay.

Seegene USA, a subsidiary of global molecular diagnostics company Seegene, Inc., has received Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration (FDA) for its Allplex HSV-1&2/VZV/MPXV Assay. The assay simultaneously detects HSV-1, HSV-2, VZV, and MPXV in a single run. According to the company, it is the first multiplex PCR test available in the U.S. designed to simultaneously detect and differentiate viral pathogens associated with ulcerative skin lesions.

The assay operates as a multiplex, real-time PCR that consolidates etiologic evaluation of clinically overlapping vesicular, pustular, and ulcerative lesions. It was developed end-to-end at Seegene USA using the company’s high-multiplex PCR technologies, including Dual Priming Oligonucleotide (DPO), Tagging Oligonucleotide Cleavage and Extension (TOCE), and Multiple Detection Temperatures (MuDT). Development was supported by the Seegene Digitalized Development System, an automated product development platform. These technologies are described as enabling comprehensive target coverage in a single reaction while maintaining the sensitivity and specificity needed for reliable multiplex testing.

Study data highlighted by the company reference a poster presented at the 2024 Clinical Virology Symposium. Scientists evaluated specimens that had previously tested negative using single-pathogen methods and found that a multiplex PCR identified HSV, VZV, or MPXV clade I/II in 54 of 966 samples. The finding underscores a population of cases that single-target testing can leave undiagnosed.

With the EUA, Seegene USA states it is positioned to expand a portfolio of locally developed multiplex PCR assays for the U.S. market. The company adds that the authorization serves as a model for its Technology-Sharing Initiative, which supports regional partners in developing and manufacturing multiplex molecular tests tailored to local needs. As that initiative grows, Seegene aims to strengthen local development and manufacturing capabilities and improve preparedness for future outbreaks.