Sanofi has doubled down on its partnership with Adagene, investing $25 million in the biotech, taking up its option on a third program and agreeing to sponsor a trial of its partner’s lead candidate.
Adagene gave Sanofi rights to two antibody candidates in 2022 in return for $17.5 million upfront. The agreement, which is worth up to $625 million per program in milestones, secured Sanofi options on two additional Adagene prospects. Sanofi has taken up its option on one of the two drug candidates. Neither party has disclosed the size of the option fee paid by Sanofi.
The discovery program picked up by Sanofi is advancing a bispecific antibody against undisclosed targets. Adagene said it has applied its masking technology and antibody engineering expertise to the program.
The masking technology shields binding domains until antibodies reach the tumor microenvironment. Tying antibody activation to the conditions in the microenvironment could minimize on-target, off-tumor toxicity in healthy tissues, enabling the use of higher, more effective doses without causing safety and tolerability problems.
Multiple other biotechs have developed rival shielding technologies, but the clinical data on the programs have been mixed. CytomX Therapeutics, Janux Therapeutics and Zymeworks are among the companies trying to extend the therapeutic window through conditional activation.
Adagene shared phase 1b/2 data on its lead program in May, linking the use of its CTLA-4 candidate in combination with Merck & Co.’s Keytruda to median overall survival of 19.4 months. CTLA-4 has been an area of focus for masking technology. Bristol Myers Squibb, the company behind CTLA-4 drug Yervoy, has a pact with CytomX but dropped a program last year.
Sanofi is supporting Adagene’s muzastotug CTLA-4 program by making a $25 million investment that will support a phase 2 trial and by sponsoring another study. The Sanofi-sponsored phase 1/2 trial will test muzastotug in combination with other anticancer therapies in more than 100 advanced solid tumor patients. Adagene still owns worldwide commercial rights to muzastotug.
The investment extends Adagene’s cash runway from late 2026 into 2027.