HDV RNA assays: Performance characteristics, clinical utility, and challenges

Area of Science:

• Hepatology
• Virology
• Molecular Diagnostics

Background:

• Hepatitis D (coinfection with HBV and HDV) is the most severe form of chronic viral hepatitis.
• It frequently leads to liver decompensation and hepatocellular carcinoma (HCC).
• Current treatment options, like pegylated interferon alpha, have limited efficacy, but new therapies are emerging.

Purpose of the Study:

• To review the challenges in developing reliable Hepatitis D virus RNA (HDV RNA) quantification assays.
• To discuss the clinical importance of accurate HDV RNA monitoring for drug development and patient management.
• To summarize the technical features and performance of existing HDV RNA assays.

Main Methods:

• Review of existing literature on HDV RNA assay development and performance.
• Analysis of factors contributing to assay variability, including viral heterogeneity and lack of standardization.
• Discussion of the role of a World Health Organization (WHO) standard for HDV RNA.

Main Results:

• Developing robust, pan-genotype HDV RNA assays is challenging due to viral diversity, rapid evolution, and RNA structure.
• Variability in RNA extraction, assay design, and lack of automation contribute to inconsistent assay performance.
• A WHO standard has aided in assay validation and inter-laboratory comparisons.

Conclusions:

• Accurate and standardized HDV RNA quantification is essential for effective patient monitoring and the development of new hepatitis D treatments.
• Addressing assay variability and improving standardization are critical for clinical decision-making.
• Further research and development are needed for reliable, universally applicable HDV RNA assays.