Rheonix has received the expanded US Food and Drug Administration (FDA) Emergency Use Authorization (EUA) for its Covid-19 MDx assay to include the use of saliva as sample.

The Rheonix Covid-19 MDx assay is an endpoint RT-PCR assay designed for the qualitative detection of nucleic acid from SARS-CoV-2, in individuals suspected of Covid-19.

The test uses nasopharyngeal swabs, oropharyngeal swabs, anterior nasal swabs, mid-turbinate nasal swabs, nasal washes, nasal aspirates and bronchoalveolar lavage (BAL) for the detection of the virus.

On 29 April 2020, the fully automated RT-PCR assay was initially authorised for use on a range of respiratory specimens under EUA.

Under the expanded EUA, the Rheonix Covid-19 MDx assay is also allowed to use with saliva specimens collected without preservatives in a sterile tube in a healthcare setting from individuals who are suspected of Covid-19 by their healthcare provider.

Rheonix scientific and clinical affairs senior vice president Richard Montagna said: “We’d like to thank our colleagues at the Cayuga Medical Center in Ithaca, New York, and Catholic Health System in Buffalo, New York, for their wonderful help in validating the use of saliva.

“Our customers are excited about the addition of this sample type, which will help them conserve precious laboratory resources. We are continuing to expand our Covid-19 tests to help address their ongoing Covid-19 testing challenges.”

Rheonix Covid-19 MDx assay runs on Rheonix Encompass MDx workstation

The Rheonix Covid-19 MDx assay is designed to run on the fully automated Rheonix Encompass MDx workstation, using the company’s Rheonix CARD cartridge technology.

The test system requires minimal training to use, and can be rapidly installed in critical locations of immediate need, said the company.

With same-day results and high scalability, laboratories are allowed to provide same-day or next-day test results for their communities or regions, instead of outsourcing their Covid-19 testing.

Using saliva samples to detect the presence of SARS-CoV-2 would simplify the sample collection process and testing workflow, while reducing the exposure of medical personnel to infected individuals, said the company.

Also, saliva is a less invasive sample collection method that serves as an alternative to nasopharyngeal (NP) swabs, and is the most prevalent sample type.

The company said that the Rheonix Covid-19 MDx Assay has not been approved by the FDA, but authorised under an EUA, only for the detection of nucleic acid from SARS-CoV-2, and not for any other viruses or pathogens.