The US Food and Drug Administration (FDA) has added Kantaro Biosciences’ COVID-SeroKlir antibody test to the emergency use authorisation (EUA) for convalescent plasma.

COVID-SeroKlir is a high-performance test for identifying the presence and precise level of SARS-CoV-2 IgG antibodies.

The revised EUA qualifies the test for detecting high titer Covid-19 convalescent plasma during manufacturing.

It limits the use of high titer Covid-19 convalescent plasma only for the treatment of hospitalised patients who are in the early stage of the disease.

Currently, Covid-19 convalescent plasma is an investigational product and is not approved or licenced for any indication.

The company noted that the test can detect SARS-CoV-2 IgG antibodies with a sensitivity of 98.8% and specificity of 99.6%.

Kantaro Biosciences board chairman Erik Lium said: “We are pleased the FDA has added Kantaro’s COVID-SeroKlir antibody test to the EUA for convalescent plasma and authorised the test’s use in qualifying convalescent plasma titers.

“We believe semi-quantitative antibody testing can play an important role in the development of advanced therapeutics for Covid-19 and appreciate that it is being recognised as such.”

The high performance of COVID-SeroKlir is the result of a two-step process, which identifies antibodies against two virus antigens, the full-length spike protein, and its receptor-binding domain.

It makes the Kantaro test precise with decreased chances for false results.

The test’s underlying technology was developed by Mount Sinai and has been used approximately 90,000 times on a highly diverse patient population.

Last November, the FDA granted EUA to COVID-SeroKlir.

Kantaro Biosciences and its manufacturing partner Bio-Techne have signed a marketing and distribution agreement with biomedical company Atrys Health for Covid-19 tests.