From Roche’s $1.4 billion licensing deal to AstraZeneca’s presidential symposium and an avalanche of clinical readouts, antibody-drug conjugates dominated Europe’s leading cancer conference over the weekend.
Two years after a craze of ADC dealmaking swept through pharma, some of those same deals were starting to bear fruit at the 2025 European Society for Medical Oncology (ESMO) Congress. Located at Messe Berlin, a series of cavernous rooms on the outskirts of the German capital that have been playing host to global exhibitions for more than 100 years, the conference saw ADCs steal the show.
Roche set the tone Friday morning by announcing a deal worth up to $1.45 billion in biobucks with China’s Hansoh Pharma for the rights to a CDH17-targeted ADC. The Swiss pharma is no stranger to the modality, having sprayed cash at a trio of ADC deals earlier in the year.
In fact, Roche considers itself something of an ADC “pioneer” thanks to early successes like lymphoma therapy Polivy, according to Charles Fuchs, M.D., the company's global head of oncology and hematology drug development.
“I've been doing this long enough to know that it's been a bit of a roller coaster, right?” Fuchs told Fierce at the conference. “You know, in 2010 everybody wanted an ADC—in 2015, nobody wanted an ADC.”
While the pharma clearly values the modality enough to stump up some big money, Fuchs is careful to put ADCs within the context of a broader oncology strategy.
“The challenge of antibody-drug conjugates, candidly, is that preclinical data for that class of drugs doesn't necessarily predict clinical efficiency,” he explained. “So, yes, we believe in the technology, but for us it's a piece of the puzzle.”
GSK has its own ADC collaborations bubbling away with Hansoh and brought data from two candidates to ESMO.
Hesham Abdullah, M.D., global head of oncology, research and development at GSK, told Fierce at the event that the renewed excitement about the modality is down to the “second iteration of ADCs.”
“What we're seeing now is we're getting much more precision with the targets, much more precision with the linker and payload combinations,” he explained. “And that is manifesting itself in terms of the clinical activity that we're seeing across different tumor types.”
This new generation of ADCs allows for dual targeting of antigens as well as combination therapies with other cancer drugs such as immune checkpoint inhibitors.
AstraZeneca strode onto the biggest stage at ESMO to shout about ADCs —namely its Daiichi Sankyo-partnered blockbuster breast cancer drug Enhertu. The pharma used ESMO’s presidential symposium Saturday to present data tying the therapy to a 53% reduction in disease recurrence or death compared to Roche’s rival ADC Kadcyla when used as an adjuvant therapy after surgery in patients with HER2-positive early breast cancer.
While AstraZeneca has tasted ADC success with Daiichi thanks to Enhertu and its follow-up Datroway, the U.K.-based Big Pharma has decided to go it alone as it explores the next generation of ADCs. The latest data for Enhertu “reinforced” AstraZeneca's belief that “ADCs are able to displace chemotherapy,” Matt Hellmann, vice president for early oncology development at the drugmaker, told Fierce at ESMO.
Meanwhile, AstraZeneca’s Enhertu partner Daiichi arrived at ESMO armed with its own ADC data for the cadherin-6-targeting raludotatug deruxtecan. The Merck & Co.-partnered therapy was tied to an objective response rate of 50.5% in a phase 2 trial for recurrent platinum-resistant ovarian, primary peritoneal or fallopian tube cancers.
But not everyone has been converted to the ADC cause. Unsurprisingly, some of the biggest skeptics include companies like Moderna, which don’t have skin in the game.
“I think there has been a lot of interest in ADCs and a lot of interest in bispecifics, and that's great, because they are making progress and helping fight cancer,” Kyle Holen, M.D., head of development, therapeutics and oncology at Moderna, told Fierce.
“My take on ADCs, however, is it’s just a different way to get chemotherapy,” he continued. “And it oftentimes comes with similar types of side effects that chemotherapy may bring.”
The modality may be stealing the spotlight at ESMO, but Holen is confident that Moderna’s pipeline of personalized cancer vaccines and other mRNA cancer candidates will set its oncology offerings apart.
“The nice thing about what we're doing, which is very differentiating, is that we can go into places that ADCs, chemotherapy, bispecifics, even PDL-1 and PD1 blockades, can't go—like very, very early settings, stage 1 cancers,” he told Fierce.
“So with that type of profile, it gives us a wider opportunity across many different indications and lines of therapy,” Holen added.