888-LAB-8082 (888-522-8082)

Email Address

Corporate Headquarters

229 49th St Brooklyn NY 11220


2180 SW 71st Terrace Davie FL 33317

Neutralizing Antibody Test

Empire City Laboratories is proud to be one of the first laboratories in the United States to provide neutralizing antibody detection testing.  Currently this is the only neutralizing antibody test for SARS-CoV-2 that has received FDA (EUA) release. This type of detection is the only hard evidence a person has to determine if they continue to have the protection necessary from the vaccine, or from prior infection. Most Covid antibody testing available only determines if a patient has IgG, IgM and/or IgA antibodies – not if they have sufficient neutralizing antibodies that block the virus from binding with the ACE2 receptor, the critical step that leads to infection.

Rapid Assessment of Immune Response to Today’s Vaccines

The cPass SARS-CoV-2 Neutralization Antibody Test is the first and only antibiody test with FDA Emergency Use Authorization (EUA) to specifically detect neutralizing antibodies. 

This blood test offers fast detection of neutralizing antibodies produced in response to vaccination or previous SARS-CoV-2 infection. 

Results are available within 24 hours of lab receipt. 

 Neutralizing antibody testing is advised after at least 7 days from known previous infection or 6 weeks after initial vaccination. Routine serial testing is also recommended for monitoring vaccine response and potential need for futher immunization. 

A Positive or Negative result for SARS-CoV-2 neutralizing antibodies can aid Health Care Providers with immunization decisions and assessment of appropriate timing required between doses or boosters. 

The test uses ELISA technology to specifcally detect neutralizing antibodies to the receptor binding domain (RBD) of he spike protein of SARS-CoV-2. 

How do neutralizing antibodies protect against Covid-19?

Neutralizing antibodies may be produced by the body in response to vaccination or previous SARS-CoV-2 infection. 

These antibodies attach to the RBD of the spike protein that facilitates entry of the virus into human cells. 

 When neutralizing antibodies are attached to the RBD of the spike protein, the virus is blocked from entering by preventing the association with the ACE2 receptor on the human cell, thereby preventing infection