Not that long ago, measles in the U.S. appeared solved, with the country declaring the virus eliminated in 2000. It’s not surprising then that the current measles drug development pipeline isn’t very robust.
“For the better part of 20 years, there hasn't been a whole lot of measles around. Pipelines take years to elaborate,” said Marc Elia, chairman and CEO of biotech company Invivyd.
But now the measles landscape has been turned on its head, with outbreaks soaring to a 30-year high.
Invivyd is one of the few companies with a measles candidate in the pipeline. Its preclinical but potential best-in-class antibody, VMS063, targets the measles Fusion protein and would work similarly to approved RSV-prevention monoclonal antibodies, Enflonsia from Merck & Co., and Beyfortus from Sanofi and AstraZeneca, the company said.
Although measles already has an effective approved vaccine on the market, which Elia calls the “Rolls-Royce” of infectious disease jabs, the current outbreak has revealed a need for therapeutic options — especially as ongoing political and regulatory controversies muddy the treatment waters.
For example, the Trump administration recently issued an executive order aimed at reducing the number of vaccines children get at doctors’ visits, which has prompted pushback from public health officials.
And amid a measles outbreak that’s currently spreading through Pennsylvania, state officials and the CDC have been butting heads about whether two recent deaths can be attributed to the disease.
With politicization and eroding public trust helping to drive down inoculation rates, having effective vaccines might not be enough.
“The limit of any vaccine is you,” Elia said, referring to both the body’s immune response and whether patients actually receive them. “These days, we're seeing pretty clearly that there are limits to what a human being wants to do vis-à-vis vaccination.”
In particular, shifts in vaccination rates are leaving holes in protection that measles is particularly well-suited to exploit.
“It is about the most infectious and transmissible thing ever characterized,” Elia said.
Although measles was once considered “an ordinary disease of childhood,” Elia believes that characterization “trivializes a lot of the burden.”
“Measles does a wonderful job wiping out your immune memory, so you actually become quite susceptible to all kinds of opportunistic infections. In rare cases, it can lead to devastating encephalitis, up to and including death,” he said.
Other vaccination gaps exist, too, such as for infants who are too young to receive the shot, leaving room for companies like Invivyd to offer an alternative, as well as a treatment for those who contract the disease.
Notably, measles also has no FDA-approved treatments.
The pipeline for measles therapeutics
Although the current MMR vaccine is cheap and monoclonal antibodies traditionally are not, Elia doesn’t foresee its measles antibody being prohibitively costly. He again pointed to Beyfortus, which costs about $550 per dose, as a possible pricing model.
“We wouldn't be doing it if we didn't think there would be a really compelling case,” he said, pointing out that when pharma companies enter the public health arena, they have an obligation toward scalability.
Invivyd has an established track record in the infectious disease space already. Its pre-exposure prophylaxis COVID-19 monoclonal antibody, Pemgarda, received emergency use authorization from the FDA in 2024. It also has other antibodies in the pipeline, including ones for COVID-19, long COVID and RSV.
But drug developers’ work in the measles arena, including Invivyd’s candidate, is still in early stages.
NanoViricides recently reported that it’s working with the FDA to bring an antiviral candidate it claims is “revolutionary” into human trials. Georgia State University also reported preclinical data about a novel antiviral drug candidate for measles in June.
On the vaccines front, GSK is advancing a combined measles, mumps, rubella and varicella shot into phase 3 clinical trials.
Even if they succeed in the clinic, the candidates are hurtling toward a market that remains tense.
Despite the executive order to split the MMR vaccine into three separate shots, impacted companies like Merck and GSK have been defiant about changing the manufacturing supply chain.
“To date, there has been no published scientific evidence that shows any benefit in separating the combination MMR vaccine into three individual shots,” a Merck spokesperson told PharmaVoice via email.
The executive order is not legally binding, and public comments by both companies about the costs and time involved in separating and re-running clinical trials for each new shot indicate they could ignore it.
“Splitting the MMR vaccine into three separate vaccines would not be a simple process,” a Merck spokesperson said. “Reformulating to create separate vaccines would require new development and testing to ensure the individual formulations retain the same efficacy and safety profile as the combination product currently licensed and used since 1978. Even under current expedited review pathways, it could take years — potentially as many as 10 — to meet the safety and efficacy requirements to obtain FDA approval.”
