Icosavax nabs $51M as synthetic virus heads toward clinic
A new biotech is using an artificial virus-like particle to try to vaccinate against the respiratory syncytial virus (RSV), a flu-like disease for which no vaccination or cure exists.
Icosavax launches with a $51 million Series A financing from Qiming Venture Partners USA, Adams Street Partners, Sanofi Ventures and NanoDimension that will propel it into a Phase I trial for IVX-121, their new vaccine for older adults.
“The magic of the VLP is that it looks and smells like a virus but it’s safe,” CEO Adam Simpson told Endpoints News. “You get all the benefits of your body giving off the danger signal without the downside.”
RSV will affect virtually all children below the age of 2, according to the NIH, inducing a mild cold for most but forcing a small percentage to be hospitalized. It can have severe consequences in older adults, annually contributing to the deaths of 14,000 Americans.
Simpson wants you to picture a soccer ball. He wants you to picture it because it’s roughly what a virus looks like if you add little antigen prongs to every black tile, and thus its roughly what their virus-like particle (VLP) looks like.
This particle works like a standard virus-based vaccine, triggering the body’s immune response by binding to lymphocyte cells and making them think the body is infected. Simpson argues this is safer than a conventional vaccine because it doesn’t involve any actual foreign virus.
This VLP, though, is critical for RSV for other reasons, he said. A vaccine for the very common virus has eluded researchers for years in large part because the virus changes form dramatically when it comes into contact with a cell. The trick, then, was to devise a vaccine that would prime the body’s immune system against the virus’s pre-contact form.
The NIH created an antigen for that form last year, Simpson said — providing a prong for Icosavax to attach to their VLP.
“What we’ve been able to do is come up with a technique to make this soccer-ball-looking structure with complex antigens and actually manufacture it,” Simpson said, “And that’s what’s never been done before.”
VLPs are already widely used for vaccines, including for inoculation against hepatitis B and human papillomavirus. But Simpson and the builders of the VLP at the Institute for Protein Design at the University of Washington told Endpoints this presents a major step forward by allowing researchers to build them from scratch, using computational models — techniques, they said, that could be used in building vaccines for other viruses that have thus far eluded researchers.
The new model works by mimicking the repetitive structure the body automatically associates with viruses, Neil King told Endpoints.
“The beautiful thing about the particle we’ve designed is they’re very robust and versatile,” King, an assistant professor at the Institute for Protein Design said. “You could use the particles to make HIV vaccines or malaria vaccines or flu vaccines as well as RSV just by swapping out different antigens.”
Icosavax will soon begin a Phase Ib trial on older adults, evaluating safety and proof-of-concept. Simpson said they will soon look at other indications but declined to name them.