At the European Society of Medical Oncology meeting in Madrid this weekend, analysts will be watching for detailed data on Merck and Moderna’s personalized cancer vaccine, Summit and Akeso’s PD-1xVEGF bispecific therapy, and a host of antibody-drug conjugates.
Antibody-drug conjugates, a groundbreaking cancer vaccine under development by Merck and Moderna and a closely watched PD-1xVEGF bispecific therapy from Summit Therapeutics and Akeso will be top of mind when the world’s foremost oncology experts convene in Madrid for this year’s meeting of the European Society of Medical Oncology.
True to its reputation, the 2026 edition of ESMO will feature some of most impactful research across biopharma, providing a stage for studies that could potentially alter how cancer is managed and treated.
“It will be a big year,” Dara Azar, associate vice president of Biotech Equity Research at Stifel, told BioSpace in an email. “We have a win in cancer vaccines and the immediate next question is, what is next? Where can investors find the next opportunity?”
Here, BioSpace previews some of the most highly anticipated presentations of the meeting, which kicks off on Friday.
Merck, Moderna seize the spotlight
Arguably the most highly anticipated presentation at ESMO belongs to Merck and Moderna. In August, the partners revealed that their mRNA-based personalized cancer vaccine intismeran autogene, when combined with the anti-PD-1 powerhouse Keytruda, extended survival without disease recurrence for patients with melanoma in the Phase 3 INTerpath-001 trial. The trial comprised 1,137 patients randomized 2:1 to receive up to nine doses of the vaccine every three weeks and Keytruda for up to one year or single-agent Keytruda for approximately one year after surgical removal of cutaneous melanoma.
On Saturday, Merck and Moderna are scheduled to present more detailed findings from this study.
“Positive Phase 3 melanoma data could move personalized cancer vaccines from a decades-old scientific ambition toward a treatment physicians may actually use at scale,” Mitchell Kapoor, senior analyst at H.C. Wainwright, told BioSpace in an email.
For Merck and Moderna, the bar is high. A previous, mid-stage readout in June found that after more than 60 months, intismeran autogene plus Keytruda cut the risk of death or recurrence by 49% versus the PD-1 blocker alone. These findings come from the Phase 2b KEYNOTE-942 trial, which enrolled 157 patients with melanoma who had undergone complete resection and who are at a high risk of recurrence. Recurrence-free survival (RFS) was the primary endpoint.
The investigational regimen also slashed the risk of metastasis or death by 59% and improved overall survival by 53%, as per the June data drop.
“The Phase 2 benchmark creates lofty expectations,” Kapoor said. “The real test here is how much of that extraordinary Phase 2 effect survives when the patient numbers scale from 157 patients to more than 1,100.”
After the topline INTerpath-001 disclosure, investors want to see the qualitative magnitude of efficacy “to better understand [the vaccine’s] competitiveness in not only adjuvant melanoma, but also other cancer types,” Jefferies Managing Director Andrew Tsai told BioSpace over email.
Stifel’s Azar agreed. “It’s important to remember that melanoma is believed to be ‘a lower hanging fruit’ for personalized cancer vaccines.” INTerpath-001 is a good first step for intismeran autogene, Azar said, but “the big question is: can cancer vaccines access the more complex indications with just the doublet or do they need more immune activation?”
The analysts could soon have at least one more dataset to reference. Tsai told BioSpace last month that he is expecting a readout for a Phase 2 trial of intismeran autogene in renal cell carcinoma later this year or in early 2027.
Meanwhile, in melanoma, investors are expecting an RFS benefit of at least 30%, Tsai said, adding that “in theory, a stronger benefit should translate to stronger commercial adoption.” A more pronounced therapeutic effect could also have “stronger readacross to other cancer types.”
Merck and Moderna are also testing the intismeran autogene/Keytruda combo in a host of other cancer types, including non-small cell lung cancer and bladder cancer.
In melanoma alone, Jefferies expects intismeran autogene’s peak unadjusted sales to top $3 billion. Unlocking other indications would broaden the vaccine’s patient pool and increase its peak sales potential “considerably,” Tsai said.
A ‘big year’ for ADCs
Aside from a detailed description of its Moderna-partnered vaccine victory, Merck is scheduled to unveil data from a Phase 3 trial of another closely watched asset: the Kelun-Biotech–partnered ADC sacituzumab tirumotecan (sac-TMT), being tested in non-small cell lung cancer (NSCLC).
“ADCs could change first-line cancer treatment while helping Merck defend its $30B-plus Keytruda franchise,” Wainwright’s Kapoor said. The Phase 3 OptiTROP-Lung06 trial combines sac-TMT with Keytruda as a first-line treatment for patients with PD-L1-negative non-squamous NSCLC.
Findings toplined in July showed that sac-TMT plus Keytruda and chemotherapy met the study’s primary endpoint, meaningfully improving progression-free survival as compared to Keytruda plus chemotherapy. There was also a positive trend in overall survival, a key secondary endpoint.
The partners did not provide specific data at the time; they will during a Sunday presentation at ESMO, which could provide a better view of sac-TMT’s benefit-risk profile in this setting.
“A large improvement with manageable side effects could keep doctors prescribing Keytruda and generate new ADC revenue as Keytruda’s primary U.S. patent expires in 2028,” Kapoor said. Keytruda brought in $31.7 billion last year, hanging on to its crown as the single top-selling pharma product.
Stifel’s Azar similarly pointed to OptiTROP-Lung06 as a potentially impactful presentation at ESMO, noting that the trial is “a great case study” for a combinable ADC challenging platinum-based chemo in a frontline lung cancer setting.
Another ADC that analysts expect to make waves at ESMO is AstraZeneca’s sonesitatug vedotin (sone-ve), which the pharma gained access to in its February 2023 licensing deal with China’s KYM Biosciences for $63 million upfront. The asset targets Claudin-18.2, a protein commonly expressed in the stomach lining.
AstraZeneca is evaluating sone-ve in the Phase 3 CLARITY-Gastric01 trial in second-line or later disease versus an investigator’s choice of comparator therapy. The study includes patients with advanced or metastatic gastric cancer, gastroesophageal junction cancer or distal esophageal adenocarcinoma with CLDN18.2 expression in at least 25% of tumor cells.
Early findings released in July showed that sone-ve aced the trial’s overall survival endpoint but only demonstrated “a trend toward improved PFS,” the other co-primary endpoint, AstraZeneca said at the time. The pharma has big plans for sone-ve and last month inked an agreement with Summit to test combinations of the ADC with the biotech’s PD-1xVEGF bispecific therapy ivonescimab, primarily focusing on gastrointestinal cancers.
As in the case of sac-TMT, analysts are closely watching for detailed data from CLARITY-Gastric01, with an eye toward getting a clear view of sone-ve’s benefit-risk balance.
“The biggest ADC opportunities could belong to drugs that replace conventional chemo, work after another ADC fails, or make effective ADC treatment easier to continue at an adequate dose intensity,” Kapoor said.
It is shaping up to be “a big year for ADCs,” Azar agreed.
Not just a Big Pharma game
While Big Pharma has typically dominated the major conferences, this year’s ESMO will also feature some of biopharma’s most promising emergent drugmakers.
Leading this list is Summit with ivonescimab. The Akeso-partnered therapy first made waves in September 2024 when it significantly outperformed Keytruda in a Phase 3 NSCLC study in China.
At ESMO on Sunday, Summit and China-based Akeso are presenting data for the candidate in a different type of malignancy: gastrointestinal cancers. In the Phase 3 HARMONi-GI1 study, the companies are combining the investigational bispecific with chemotherapy for the first-line treatment of patients with advanced biliary tract cancer—and pitting the regimen against AstraZeneca’s Imfinzi plus chemotherapy.
Topline results in August showed that the ivonescimab combo significantly improved overall survival versus the Imfinzi control, meeting the study’s primary endpoint. The trial also revealed significant benefits in progression-free survival and objective response rate, key secondary endpoints. The partners did not provide specific data at the time but are expected to at ESMO.
“It’s interesting that [ivonescimab] continues to deliver positive Phase 3 results from China, also outside of lung cancer and against different immunotherapy comparators,” Stifel’s Azar told BioSpace.
Ivonescimab is under FDA review for advanced non-squamous NSCLC, with a decision expected by Nov. 14. Summit has not specified a timeline for FDA submission in other solid tumor indications.
Also arriving in Madrid is Incyte Corporation, bringing what Wainwright’s Kapoor calls “one of the most important catalysts at ESMO as pancreatic cancer has become a multibillion-dollar opportunity for RAS-targeted drugs.”
The biotech is scheduled to present data from the Phase 3 DAWN-303 study of INCB161734, an investigational oral inhibitor that selectively targets the G12D-mutated versions of the KRAS protein.
In this arena, Incyte is facing off against Revolution Medicines, which is advancing zoldonrasib, an asset with a similar targeting profile. The selective G12D inhibitor achieved an 82% overall response rate when used with the chemotherapy backbone mFOLFIRINOX, as per a Phase 1/2 readout in June.
Revolution made waves in April when its RAS(ON) multi-selective, non-covalent inhibitor daraxonrasib doubled overall survival in a Phase 3 study in pancreatic cancer. The drug was greenlit in August with the brand name Rasonque, but FDA review documents released following the approval showed that the drug performed less well in participants with G12D mutations, leading to an overall response rate (ORR) of 24%, as compared with the 33% ORR seen across the study and the 50% ORR seen in patients with a G12V mutation.
For Incyte, keeping disease under control in around four out of five patients would be “compelling” given manageable toxicity, said Kapoor, who is looking forward to INCB161734’s readout at ESMO. At that threshold, he continued, “the focus becomes how much of the first-line opportunity Incyte can grab.”
