The Indian Council of Medical Research has approved the use of “OmiSure”, test kits developed by the Tata Medical and Diagnostics (Tata MD) to identify the new Omicron variant. This home-grown testing kit for taking samples from the nose and throat will be available for commercial use from January 12.
It has been developed by a team headed by Dr V Ravi, former head of neurovirology, NIMHANS and currently head of R&D, Tata MD, is listed on the ICMR website as the only kit approved specifically for Omicron detection.
Dr Ravi told The Indian Express that OmiSure is neither a home testing kit and nor a self-test kit. “It detects viral genetic material and non-viral antigen. It is not a Rapid Antigen Test (RAT). Polymerase Chain Reaction (PCR) can only be done in laboratories. It requires special equipment, trained people and a certain amount of bio-safety. PCR has been done right from the beginning of the pandemic. OmiSure is a real-time PCR so it is not available for public use at home.”
He said he started working on the development of the kit just a couple of days after the Omicron was announced. “Right after the first case of Omicron was reported, we had submitted the kit for an ICMR evaluation. This is the fastest-developed kit globally. From the specimen collection to the reporting like other PCRs, the kit takes a maximum two and a half hours to give the results.”
Dr Ravi shared that there are plans to export the kit globally as it has the advantage of being able to screen S-gene dropout as well as specific detection.
The kit can also help detect any other circulating SARS-CoV-2 variant. OmiSure is a single tube, fully multiplexed test (provisional patent application filed). It just has two checks in place for Omicron detection without compromising the ability to detect other SARS-CoV-2 variants.
Tata MD said the kit evaluated with the ICMR recorded 100% sensitivity and 99.25% specificity for detection of variants of SARS-CoV-2, including Omicron. OmiSure is said to be the first test to use a combination of two S-gene viral targets to identify the new variant Omicron. The initial target is based on S-gene dropout or S-gene target failure (SGTF); the second is based on S-gene mutation amplification (SGMA).
The company has begun working to scale up production capability, supply chain and raw material inventory to deliver two lakh OmiSure tests per day. It said the kit can help cut half the cost and complexity of first-line COVID-19 testing and Omicron screening. “Most states have adopted a dual testing strategy at the point of first-line testing, where samples are first tested with cost-effective regular COVID-19 RT-PCR tests and then, positive samples are screened for Omicron with a more expensive SGTF assay and prioritized for sequencing.”