Measles Antibody VMS063 and Immune Amnesia: Michael Mina, MD, PhD

At IDWeek 2026, held October 21-24 in Washington, DC, Michael Mina, MD, PhD, chief medical officer and chief epidemiologist of Invivyd, spoke with The American Journal of Managed Care^® (AJMC^®) about the company's investigational measles monoclonal antibody VMS063, the lasting immune damage measles can cause, and what payers can learn from the rollout of pediatric respiratory syncytial virus (RSV) monoclonal antibodies.

This transcript has been edited for clarity.

AJMC: What is VMS063, and what did your poster show about how it neutralizes the measles virus?

Mina: VMS063 is a monoclonal antibody being developed by Invivyd against measles. The 063 is a play on the fact that the measles vaccine was first licensed in the US in 1963, which happens to be exactly 63 years ago. As we move into the new future of where immunizations are going—how do we create options and choices and new modalities for treatment and fill in the gaps where vaccines currently don't?—we figured that this was a unique time to pay some homage to the vaccine and what it's done, but also recognize what we're building, which is really the world's first, and potentially the best-in-class monoclonal antibody against measles.

What we showed in the poster is that it's a very potent neutralizer of the measles virus that works by binding and neutralizing the fusion protein, or what's called the F protein, in measles. This is a protein that measles uses to disseminate within the body. Once it enters the body, the measles virus uses the F protein to get cells to fuse together, and it allows itself to transmit throughout cells that way without being identified too easily by the immune system. By neutralizing the F protein, the fusion protein, we're able to stop that dissemination and stop replication, and ultimately, it enables a very potent inhibitor of the virus, ideally in humans. Thus far, all of this work has been preclinical, in the laboratory.

AJMC: These results come from in vitro neutralization assays. What do clinicians and health systems need to keep in mind when interpreting preclinical data like this before clinical trials begin?

Mina: One of the nice things about a monoclonal antibody is that it works very simply. That is to say, if it neutralizes the virus in vitro, it's probably going to neutralize the virus in vivo. That's usually the case, and that's because the mechanism is so clean. An antibody floats around and finds its cognate partner—in this case, a measles F protein—and binds, and as long as that binding is sufficient to prevent that protein from doing what it's supposed to do, in this case driving fusion across cells, then it's going to neutralize.

How would a clinician interpret this? I think a clinician or a health system would look at this data and say it's interesting data. It's preclinical, so there's not too much for a health system to really concern themselves with right now. But suffice it to say, this is very strong preclinical data about a monoclonal antibody in the hands of a company like Invivyd, which is really doing a tremendous job, I would say, at perfecting the translation of antibodies from the preclinical to the clinical stage.

The message we would like to project is that we're aiming to have the first therapeutic and preventive monoclonal antibody, and really just the first directed treatment or prevention against measles that is not reliant on a vaccine, that's ever been created, and so we're very excited to bring this forward. We're going to be accelerating our clinical programs; we anticipate [entering the clinic] in 2027. In this case, fortunately or unfortunately, I would argue we are mostly rising to the unfortunate need that now exists in the United States regarding measles outbreaks.

But regardless of the US and other high-income countries like the US, measles has never been eliminated in much of the world. In many countries, there continue to be enormous outbreaks and an enormous amount of morbidity and mortality associated with it. Right now, the world has really only ever had vitamin A as a potential therapeutic, but that really only works in vitamin A–deficient children to potentially support their ability to get through an infection. Then we have things like IVIG [intravenous immunoglobulin], which is just pooled antibodies from people, so it's a very ineffective or inefficient way of treating measles and comes with other risks. We think that bringing an antibody to market for treatment for the global population is going to be a really important addition to our arsenal.

AJMC: Your earlier research showed that measles infection can wipe out existing antibodies against other pathogens. How does that "immune amnesia" shape the case for a measles treatment, beyond managing the acute infection?

Mina: One of the most insidious aspects of a measles infection is what can happen even if you get through that acute infection. One of the discoveries that I helped lead—back in 2015 and 2019, we published a couple of seminal papers that have now been put into textbooks^1,2—is that measles actually eliminates your preexisting immune memory.

As a child grows up, or as any of us grow up, we develop immunological memory, which is protective against all sorts of things. We get through those first 5 or 6 years of life, and we all know that kids get really sick during the first years of life. That's not because they're, quote, "weak." It's because they haven't yet developed their immunological memory repertoire to protect them. They haven't built their defenses. So you grow up, and you build all those defenses, but then you get a measles virus infection. If that happens, it has the potential to wipe out a huge amount of those defenses that you spent a lifetime building up, and that puts you at risk for other infectious diseases, potentially for years, as you try to rebuild those defenses again.

It's sort of like if you're guarding a castle and all of a sudden all the defenses around the castle are just eliminated. Then you're vulnerable, and you have to spend months or years rebuilding those defenses, all the while being a little bit more, or greatly more, susceptible to invasion. That's really what measles does to the immune system.

So by preventing measles with a monoclonal antibody, or by treating measles very early in an infection after an exposure—what we might call postexposure prophylaxis—or actual treatment, we anticipate that we will greatly diminish the damage that measles does to the immune system. In postexposure prophylaxis, we might completely prevent that immunological damage that measles might do, and therefore hopefully have extended benefits that really extend well beyond prevention of measles alone, to the preservation of immunological memory as well.

AJMC: Looking at how pediatric RSV monoclonal antibodies were rolled out, what lessons about access, coverage, and uptake should payers and health systems take on board as measles antibodies head toward clinical development in 2027?

Mina: We look at things like Beyfortus [nirsevimab] and the RSV monoclonal antibodies as proof that there is interest and demand. The uptake of the RSV monoclonal antibodies in early childhood has been tremendous. There is always a question: Will physicians adopt a new technology? Will patients adopt a new technology? Will they be interested? I think the very swift adoption teaches us a couple of things. It seems sometimes like people are really focused on vaccines, but from a patient's perspective and from a physician's perspective, what Beyfortus tells us is that people aren't focused on the vaccine; they're focused on the protection. Getting a monoclonal antibody for RSV has been a life-changing event at a population level to prevent RSV in the most vulnerable individuals. So I think we should expect that we're going to see a very swift adoption of measles monoclonals in our youngest infants as they're born to fill in that gap before you can get a vaccine.

Certainly, as the development program and the clinical program for 063 move forward, we're going to be really working, ideally, with the federal government and with groups like ACIP [Advisory Committee on Immunization Practices], the CDC, and NIH to have those discussions: Where does this fit into a vaccine schedule? As we move forward, our expectation is that this will become part of what we would think of as the immunization schedule. ACIP is immunization practices, not vaccine practices. Although it's normally considered focused on the vaccine schedule, it's actually around immunizations.

How will payers think about it? I think that will depend a lot on how ACIP addresses new antibodies like this. But our expectation is it will be considered as part of the routine immunization practices in America, and so payers should start to think about this very much like they think about how they're paying for vaccines today.

References

1. Mina MJ, Metcalf CJE, de Swart RL, Osterhaus ADME, Grenfell BT. Long-term measles-induced immunomodulation increases overall childhood infectious disease mortality. Science. 2015;348(6235):694-699. doi:10.1126/science.aaa3662

2. Mina MJ, Kula T, Leng Y, et al. Measles virus infection diminishes preexisting antibodies that offer protection from other pathogens. Science. 2019;366(6465):599-606. doi:10.1126/science.aay6485