Days after halting lead asset, Sotio signs $740M deal to access Synaffix's ADC tech

Mere days after announcing that trials for its lead IL-15 asset have been halted over poor data, Sotio Biotech has unveiled plans to delve deeper into antibody-drug conjugates (ADCs) courtesy of deal worth $740 million in biobucks.

Specifically, Czech Republic-headquartered Sotio wants in on Synaffix’s ADC technologies, namely the antibody conjugation platforms GlycoConnect, HydraSpace and select toxSYN linker-payloads. These platforms are meant to design ADCs from any antibody with the goal of delivering medicines with enhanced efficacy and tolerability.

The agreement is centered on one initial ADC program, with the option to add two additional programs later on. Synaffix will be responsible for the manufacturing components specifically related to its own technologies, with Sotio handling research, development and commercialization of any resulting ADCs.

In return, Synaffix will be eligible for a total of $740 million that includes signature, target nomination and milestone payments, along with a bite of the royalities should the research bear fruit.

Sotio CEO Radek Spisek said accessing Synaffix’s tech will ensure his company “remains at the leading edge” of the solid tumor space. 

“This collaboration combining Sotio’s deep expertise in solid tumor drug development with Synaffix’s clinical-stage platform technology will drive important new innovations for the benefit of patients,” Spisek added.

Today's news comes after Sotio confirmed last week that it was halting trials of its most advanced candidate, an IL-15 superagonist called nanrilkefusp alf, over "insufficient efficacy" in interim data. The biotech had already been turning its attention toward ADCs, where it has one asset in an early-stage trial for gastric and pancreatic cancers, alongside CAR-T therapies in preclinical development.

Swiss CDMO Lonza acquired Synaffix for 100 million euros ($105 million) upfront in June, and today’s deal is a reminder that the Dutch biotech’s ADC expertise is in high demand. The Amsterdam-based company also received a Big Pharma seal of approval at the start of the year, when Amgen signed a $2 billion cancer-focused pact.

“The selection of our ADC technologies by a seasoned ADC player like Sotio is a strong recognition of the potential of these technologies to maximize the therapeutic index of ADCs,” Peter van de Sande, Head of Synaffix, said in the Oct. 16 release.