VaxEffect Test Allows Clinicians to Measure and Track Immune Response to COVID-19 Vaccination

FlowMetric, Inc., discusses its VaxEffect, an immune monitoring platform and how it can be used to measure COVID-19 vaccine responses.

A new vaccination immune response monitoring platform is going beyond a simple “Yes/No” and providing clinicians and patients more quantitative data regarding immune response to COVID-19 vaccination. The test could be especially beneficial for immunocompromised patients by informing timing for boosters down the road.

VaxEffect, created by FlowMetric Life Sciences, Inc., just recently launched. Renold Capocasale, CEO and founder of FlowMetric, and Grant Morgan, PhD, PMP, executive vice president for FlowMetric and general manager of VaxEffect, spoke this week on the platform, its clinical application, and future plans for immune response tests for other vaccines beyond COVID-19.

Transcript has been edited for clarity and length.

Q: What is the background of FlowMetric?

Renold Capocasale: FlowMetric Life Sciences was created over a decade ago as a contract research organization (CRO) dedicated to advancing pharmaceutical and biotech drug development initiatives. We specialize in cellular analysis as it relates to interrogating the immune system to address safety, efficacy, and potency of new drugs coming to market. We are divided—or broken up into—2 companies, so our CRO division, which has pharmaceutical and biotech clients, and, more recently, our diagnostic division, which is where we develop LTDs to address various test needs and VaxEffect falls under that division.

Q: What was the inspiration behind VaxEffect?

Capocasale: VaxEffect as a platform really was inspired quite some time ago when I was a researcher at [Johnson & Johnson] in the lab. My first son was born and, of course, trying to be very responsive for all of the background that I had in immunology was certainly very keen on following his vaccination schedules. I remembered quite distinctly asking pediatricians at every vaccination meeting that we had if it would be okay if I could get titers for my son, and I always posed the question, ‘Well, how do we know actually that he's generated a good immune response?’ And literally, pediatricians kind of chuckled and said to me, ‘Well, we don't really do that.’ So that was the really the genesis of the idea back when I was a bench scientist, and I took that along. When FlowMetric Life Sciences launched its diagnostic division back in 2015, we were certainly motivated to come back to that question. Certainly, at this point, the perfect storm of COVID-19 appearing on the scene made it obvious which vaccination we should begin with in terms of developing specifically a test around looking and measuring that specific immune response to a vaccine. That was the genesis of COVID-19 VaxEffect.

Q: What is the science behind VaxEffect? How does it work?

Grant Morgan, PhD, PMP: The science [is] based on flow cytometry, where we're able to actually detect levels of antibodies specifically in the blood of the patient that provides the sample. It detects a quantitative level of those antibodies, and then provides a very easy-to-understand output report that shows whether you've responded to the vaccine or have been previously exposed to the virus, and also how much of a response you generated as measuring quantitatively the level of antibodies you have in your system.

Unlike other serology tests available today, the VaxEffect test is actually built on multiplex flow cytometry and what that enables us to do is to detect 2 proteins associated with the COVID-19 virus. The first protein is called the nucleocapsid protein and this is actually found hidden inside the virus. You are only exposed to that protein if you've been previously infected by the virus. You'll generate antibodies to that, and that's able to be detected by our tests.

The second protein that the test is able to identify is the RBD protein that's on the spike part of the virus. This is actually what's used in all the vaccines that are given to everybody, and so we are able to uniquely identify over a wide quantitative range the level of antibodies you've generated to that vaccine based on the immune response to the RBD spike protein.

One of the unique things about the VaxEffect vaccine immune response tests is that, unlike other tests, it's actually able to offer 4 unique answers or responses to questions that you may have. The first one is: Did I actually generate an immune response? It's a quantitative assessment, yes/no, to generating immune response to the vaccine you received.

The second one is, because of the uniqueness of the platform we use in flow cytometry, you're able to quantify the amount of vaccine immune response that you've generated over a very wide dynamic range, and this is called the VaxEffect Score. This will not only tell you how well you've generated an immune response, but you will be able to actually see where your immune response level is in comparison to other people who've taken the test.

The third component is that you can actually track over time that immune response. We envision [a scenario] where a patient would have a VaxEffect test to see what their immune response was like to the vaccine they received, and then have repeat tests every 3 months [or] 6 months to see whether they are maintaining that specific immune response to the vaccine they received.

The last component of this is whether you have a prior exposure to the virus. Forty percent of people who were exposed to the virus did not know they had generated or been exposed to the virus, and therefore generate an immune response. We're able to actually uniquely identify those individuals who have been exposed to the virus. With this test what we think we have is something where you can uniquely quantify and track your immune response to the vaccine you received or to the COVID-19 virus that you were previously exposed to.

Q: Who is the target user for VaxEffect?

Morgan: We believe the primary user for the VaxEffect immune response test actually will be the physician's office. We believe that doctors will be really interested in utilizing the test to really understand their patient's immune response to the vaccine or if they've been previously exposed to the virus. What we've heard is that, especially in immunocompromised patients, doctors are unable to provide a real definitive answer as to whether the patient [has] actually created immune response to the vaccines they've received. This is tremendously important when patients are thinking about returning to their everyday lives, returning to interacting with their families, going on vacation.

For most of us, we don't even think about it now. We think we've been vaccinated, and we just assume we’ve had a good immune response. For immunocompromised patients, it's a different story. They really don't know if they've created that robust immune response, and the doctors are unable to provide the information. We think this test, for a healthcare provider, will be able to turn to that patient and say, ‘You know what, I can actually now give you a simple blood test and I can tell you the response you've made.’ And because it's extremely quantitative over a very wide dynamic range, that doctor will be able to say to the patient whether they've even generated a weak immune response, which may indicate that they could potentially get a booster shot, which would increase their antibody levels, and then make them feel more comfortable about returning to the world and environment than they used to.