Clinical evaluation of the Altostar HDV RT-PCR Kit 1.5

BACKGROUND: Detection and quantification of hepatitis D virus RNA is essential for diagnosis and treatment of chronic hepatitis D virus (HDV) infection. This study evaluated the diagnostic performance of the Altostar HDV RT-PCR Kit 1.5 in real-world clinical samples with and without treatment with bulevirtide (BLV). METHODS: Plasma samples of 40 patients with chronic HDV infection were analyzed with the Altostar HDV RT-PCR Kit 1.5 and compared to the local standard, the RoboGene HDV RNA Quantification Kit 2.0, with additional analyses of corresponding serum and plasma samples and on-treatment samples during BLV therapy. RESULTS: HDV RNA levels in plasma samples quantified by both assays showed a significant positive correlation. All samples were quantifiable by Altostar 1.5, whereas two samples were undetectable by Robogene 2.0 During BLV therapy, mean baseline (BL) and follow-up (FU) HDV RNA levels were comparable between the two assays. There was a similar proportion of patients with virological response (Altostar 1.5: 75% [n = 15/20] vs. Robogene 2.0: 70% [n = 14/20]), whereas the proportion of samples with undetectable HDV RNA at FU was considerably higher in measurements with Robogene 1.5 (40% vs. 0%). CONCLUSIONS: HDV RNA levels quantified by the Altostar HDV RT-PCR Kit 1.5 were comparable to the local standard. The higher number of detectable samples may reflect increased sensitivity, occasional false-positive results with Altostar 1.5, or the impact of automated extraction in the Robogene workflow. Importantly, treatment response during BLV treatment was not influenced by the type of quantification assay.