Performance of the FREND™ COVID-19 IgG/IgM Duo point-of-care test for SARS-CoV-2 antibody detection

ABSTRACT

Purpose

In the context of the current COVID-19 pandemic, multiple serological assays for the detection of severe acute respiratory syndrome 2 (SARS-CoV-2) immune response are currently being developed. This study compares the FREND^TM COVID-19 IgG/IgM Duo (NanoEntec) a point of care (POCT) assay with the automated Elecsys anti-SARS-CoV-2 electrochemiluminescent assay (Roche Diagnostics).

Methods

Serum samples (n = 81) from PCR-confirmed SARS-CoV-2 positive patients at different time points after the onset of symptoms were analyzed with both assays. An additional 24 serum samples with cross reactivity potential were also included.

Results

The sensitivity of the COVID-19 IgG/IgM Duo assay was higher as compared to the Elecsys anti-SARS-CoV-2 assay, especially when using the combined IgM/IgG result in samples analyzed within 6 days after the onset of symptoms (46.2% vs. 15.4%). The sensitivity of both assays increased with increasing time interval after the onset of symptoms and reached 100% for the COVID-19 IgG/IgM Duo assay in samples taken 14 days or more after symptom onset. Specificity of the COVID-19 IgG/IgM Duo assay was 95.8% for IgM, 91.7% for IgG and 87.5% for the combination of both.

Conclusion

This study shows that the sensitivity of both assays was highly dependent on the time interval between the onset of the COVID-19 symptoms and serum sampling. Furthermore, rapid serological testing for SARS-CoV-2 antibodies by means of the FREND^TM COVID-19 IgG/IgM Duo POCT assay showed a comparable diagnostic performance as the reference automated immunoassay.

KEYWORDS:

• SARS-CoV-2
• immunoassay
• point-of-care testing
• IgG/IgM
• COVID-19

Declarations

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

This work forms part of RECOVER (Rapid European COVID-19 Emergency Response research). RECOVER is funded by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101,003,589.

Disclosure of potential conflicts of interest

No potential conflict of interest was reported by the author(s).