Beyfortus-maker AstraZeneca enters RSV vaccine race with $800M Icosavax acquisition

It looked for a while like AstraZeneca was planning to back out of the vaccines business for good, but the acquisition of respiratory syncytial virus (RSV) shot developer Icosavax suggests the British Big Pharma plans to be a player for a while longer.

AstraZeneca, which developed and manufactures the approved RSV antibody Beyfortus, is paying $800 million in upfront cash for the Seattle-based biotech. The deal value equates to $15 per share, which the pharma noted was a 43% premium on Icosavax’s share price at market close yesterday. Icosavax’s shareholders will also be in line for another $5 in cash per share if certain regulatory and sale milestones are hit.

At the center of the deal is Icosavax’s phase 3-ready protein virus-like particle (VLP) vaccine, dubbed IVX-A12, which targets both RSV and human metapneumovirus (hMPV). To coincide with the deal announcement, Icosavax released interim data from a phase 2 trial of the candidate, which saw 264 healthy adults aged 60-85 years receive a single dose of IVX-A12—either alone or in combination with CSL Seqirus’ adjuvant MF59—or placebo.

Icosavax reported this morning that IVX-A12 “induced robust immune responses” to both RSV and hMPV after 28 days among both the adjuvant and non-adjuvant cohorts. The trial also reconfirmed the safety data seen in phase 1, with no vaccine-related serious adverse events reported in the phase 2 trial.

While this year saw GSK get the first adult RSV vaccine to market, closely followed by Pfizer, there are still no treatments or preventative therapies on the market for hMPV and no combination vaccines for RSV available.

The fact AstraZeneca is willing to sign off on north of $1 billion—once the milestones are taken into account—can be explained by IVX-A12’s position as, in the pharma’s words, “the most advanced investigational vaccine targeting both RSV and hMPV” as well as its “differentiated profile versus currently approved RSV vaccines.”

The aim of VLP vaccines is to mimic “how naturally occurring viruses appear to the body’s immune system,” AstraZeneca explained. This is why the company is hoping that IVX-A12 will have the edge in terms of immune response, durability and fewer side effects than the recent crop of approved options already out there.

“This virus-like particle vaccine technology has the potential to transform prevention against severe infectious diseases, including RSV and hMPV,” AstraZeneca’s EVP of vaccines and immune therapies Iskra Reic said in the release. “With the addition of Icosavax’s phase 3-ready lead asset to our late-stage pipeline, we will have a differentiated, advanced investigational vaccine, and a platform for further development of combination vaccines against respiratory viruses.”

“This aligns with our strategy to deliver a portfolio of therapies to address high unmet needs in infectious diseases, and our ambition to protect the most vulnerable patients who have high risk of severe outcomes,” Reic added.

The deal signals an intent by AstraZeneca to keep a foot firmly in the vaccine space. The Big Pharma entered the year with its vaccine pipeline emptied out despite having brought one of the world’s most widely used COVID-19 shots to market only a few years earlier.

When asked by Fierce Biotech at an event back in February whether AstraZeneca’s vaccine strategy had reached the end of the road, CEO Pascal Soriot was keen not to make any broad statements. However, Reic did tell Fierce at the same event that “we are still looking into COVID but also beyond COVID in the viral pathogens where there is an unmet need, for example, like flu or RSV.”

It made sense that AstraZeneca was continuing to keep an eye on the RSV vaccine market, which is set to become one of the pharma industry's next major battlegrounds, with analysts pegging the potential opportunity at more than $10 billion. Aside from Pfizer and GSK, Moderna has posted positive phase 3 results this year.

Since securing FDA approval for Beyfortus in July as a preventive for RSV lower respiratory tract disease in babies, AstraZeneca and its partner Sanofi have been in the spotlight over shortages of the prophylactic antibody. Last month, the White House stepped in to help ensure the same issues wouldn’t arise in the next fall and winter virus season.