Merck bags options on Evaxion's AI-designed vaccines, offering small upfront and big back end

Merck & Co. has picked up options on two Evaxion Biotech vaccine candidates, paying $3.2 million and dangling more than $1 billion in milestones for the chance to pick up preclinical prospects against gonorrhea and an undisclosed infectious agent.

The deal covers two candidates derived from an Evaxion technology that uses AI to identify antigens that can trigger robust, protective immune responses. The platform, called EDEN, ranks antigens based on their ability to elicit an immune response. Evaxion applied a second technology, which identifies both viral B-cell antigens and multiple T-cell epitopes, to the vaccine against the undisclosed infectious agent.

Merck is placing a small bet to get a closer look at the two candidates. In return for the upfront payment, Merck has secured the option to license the vaccines for up to $10 million next year. If the drugmaker takes up that option, Evaxion will be in line to receive up to $592 million per product.

Evaxion developed the gonorrhea vaccine candidate, called EVX-B2, by processing 10 proteomes of the bacterium using EDEN. The Danish biotech included several different antibiotic resistance profiles among the selected strains. After identifying vaccine antigens, Evaxion evaluated them with different adjuvants in vivo to test antigen-specific antibody responses, bactericidal activity and protection.

Less is known publicly about the second candidate, which is called EVX-B3. Evaxion began working with Merck on the project in 2023. The candidate targets a “pathogen associated with repeated infections, increasing incidence and often serious medical complications, and for which no vaccines are currently available,” the biotech said. Evaxion is yet to disclose the identity of the pathogen. 

Merck and Evaxion’s work on EVX-B3 is part of a broader relationship. The Big Pharma’s corporate venture arm was part of Evaxion’s $5.3 million private placement last year and owns almost 10% of the biotech’s shares, making it the single largest shareholder. Merck is also supplying its checkpoint inhibitor Keytruda to Evaxion for use in a phase 2 cancer vaccine trial.