Sanofi starts Phase 3 combination vaccine trial in Europe

Sanofi has begun a Phase 3 influenza-COVID-19 combination vaccine trial in Europe, testing its high-dose influenza shot together with Novavax's COVID-19 shot, Nuvaxovid, in adults aged 60 and older. The study will assess safety and immunogenicity, meaning whether the pairing prompts an immune response, according to Novavax, which announced the start of the trial on October 29.

Sanofi dosed the fifth participant in the European Union trial on October 28, according to a Novavax filing with United States securities regulators. That dosing step triggered a $125 million milestone payment from Sanofi under the companies' collaboration and license agreement, and Novavax said it expects to receive the money by the first quarter of 2027.

John C. Jacobs, Novavax's president and chief executive, said the partnership has generated over $1 billion in revenue for Novavax to date. He described the trial as "an important step" toward Sanofi's stated aim of being among the early movers in the combined-shot segment.

The candidate pairs Sanofi's marketed Efluelda/Fluzone High-Dose influenza vaccine with Nuvaxovid, Novavax's protein-based COVID-19 vaccine. Novavax builds its vaccines around protein-based nanoparticles and its Matrix-M adjuvant, a technology designed to strengthen the immune response to the protein it carries. The trial focuses on older adults, the group the companies enrolled for this stage of testing.

What the trial will test

Late-stage trials are typically the final round of human testing before a company seeks regulatory approval, and this one has a narrow question to answer: whether the two shots work safely together and prompt the expected immune response when given as a pairing. No safety or immune-response results from the trial have been disclosed yet. The news so far is that dosing has started, not how well the pairing performs.

The commercial case for the pairing rests on scale. Novavax put the combined global value of the flu and COVID-19 markets at more than $10 billion, citing revenue disclosures from the leading market participants, and pointed to a significant burden of disease from both viruses. A shot that covers both illnesses in a single regimen would spare patients and clinics the scheduling and delivery of separate appointments across a respiratory season, though the trial must clear the safety and immune-response bar regulators will demand.

Separately, Sanofi Canada said Nuvaxovid will be available across Canada for the coming respiratory season through provincial programs and most private insurers, according to a Sanofi Canada announcement. The shot uses protein-based technology rather than mRNA, and Sanofi Canada said pivotal late-stage studies showed efficacy of about 90% against symptomatic COVID-19. In Ontario, availability through health-care provider offices and public health units was expected to begin the week of October 26, with pharmacies to follow.

Sanofi Canada said the shot was already available in British Columbia, Alberta and Quebec when the announcement was made. In Canada, Nuvaxovid is indicated for people aged 12 and older for active immunisation against COVID-19, and Sanofi Canada described its tolerability profile as favourable for seasonal vaccination. The payment structure ties Novavax's income to Sanofi's progress through development milestones and, later, to sales through royalties.

What comes next

Novavax remains eligible for royalties on Sanofi's sales of Nuvaxovid, plus a $75 million milestone when the manufacturing technology transfer completes, an event the company expects in the middle of next year. A further $225 million milestone is tied to a United States launch, once Sanofi meets the clinical and regulatory requirements there. The agreement also covers milestones and royalties for new vaccines Sanofi builds with Novavax's Matrix-M adjuvant.

Novavax cautioned that United States requirements may differ from those in other markets and that additional studies may be needed to support a filing there, so the European trial alone does not set a timeline for the American market. Investors and public health watchers will instead look for the trial's safety and immune-response data, and for word on whether the manufacturing transfer stays on schedule.

More health coverage is available on genznewz.com's health pages, and the site's health section will carry follow-up reporting as trial results emerge.