Clinical evaluation of a SARS-CoV-2 RT-PCR assay on a fully automated system for rapid on-demand testing in the hospital setting

Background

The ongoing SARS-CoV-2 pandemic presents a unique challenge for diagnostic laboratories around the world. Automation of workflows in molecular diagnostics are instrumental for coping with the large number of tests ordered by clinicians, as well as providing fast-tracked rapid testing for highly urgent cases. In this study we evaluated a SARS-CoV-2 LDT for the NeuMoDx 96 system, a fully automated device performing extraction and real-time PCR.

Methods

A publicly available SARS-CoV-2 RT-PCR assay was adapted for the automated system. Analytical performance was evaluated using in-vitro transcribed RNA and clinical performance was compared to the cobas 6800-based reference assay within the lab.

Results

The NeuMoDx-sarbeco-LDT displayed good analytical performance with an LoD of 95.55 cp/ml and no false positives during evaluation of cross-reactivity. A total of 176 patient samples were tested with both the Sarbeco-LDT and the reference assay. Positive and negative agreement were 100% and 99.2% respectively. Invalid-rate was 6.3%.

Conclusion

The NeuMoDx-sarbeco-LDT showed analytical and clinical performance comparable to the cobas6800-based reference assay. Due to its random-access workflow concept and rapid time-to-result of about 80 minutes, the device is very well suited for providing fast-tracked SARS-CoV-2 diagnostics for urgent clinical samples in the hospital setting.

Highlights

• A publicly available SARS-CoV-2 RT-PCR assay was adapted and evaluated on the open mode of the NeuMoDx 96 system (Qiagen)

• The assay showed comparable analytical and clinical performance to the reference assay

• Fast turn-around times (80 minutes) and random-access workflow of the system makes the assay well suited for urgent clinical samples.