The European Society for Medical Oncology (ESMO) Congress 2026 in Madrid brought together leading oncology professionals, researchers and industry experts from around the world to share the latest research, innovations and developments in cancer treatment and patient care.
Here, Pam Hallworth (Director) shares Adelphi Research’s perspective from the conference.
Reflections from ESMO 2026
Friday 23rd October – Monday 26th October
Broad Reflections
As ever, ESMO 2026 was a whirlwind. Our key takeaway is the growing complexity of treatment decisions. More tailored treatments give clinicians greater flexibility in responding to different patients, but they also make it harder to know which is the right option, when to use it, and how long the benefit is likely to last within an evolving paradigm.
ESMO highlighted that a promising trial outcome is only the beginning. It does not always tell us whether a treatment will change practice or improve patients’ lives. The challenge now is to make sense of the growing body of evidence and turn it into decisions that are more precise and meaningful in day-to-day care.
Key Reflections
Friday 23rd October
1. Oesophageal cancer: moving detection earlier
Rebecca Fitzgerald’s lecture connected the EndoSign capsule-sponge approach and BEST4 screening with pathology, molecular markers and AI-assisted triage. It showed the potential to identify risk and diagnose oesophageal cancer earlier, before symptoms occur.
Earlier diagnosis may also make more effective, organ-preserving treatment possible. To us, the key question is no longer whether we can detect disease sooner, but whether our screening pathways are ready when we do.
2. Lung cancer: sex and gender as evidence gaps
Pilar Garrido’s lecture highlighted differences in treatment outcomes and toxicity in women with lung cancer. It showed gaps in trial representation and sex-specific evidence, reinforcing that uncertainty remains about whether the benefit of immunotherapy differs by sex.
A recurring theme across ESMO 2026 was the need to move beyond averages and better understand variation between patients. This session highlighted that sex and gender remain important dimensions where more evidence is still needed.
3. Perioperative IO in bladder cancer: not all Phase III studies tell the same story as two fail to meet endpoints
Results from two Phase III studies in resectable, muscle-invasive bladder cancer added to the evolving perioperative immunotherapy story. Despite evaluating pembrolizumab (KEYNOTE-866) and nivolumab (ENERGIZE) alongside cisplatin-based chemotherapy, neither study achieved a statistically significant improvement in event-free survival, and ENERGIZE additionally missed its co-primary pathological complete response endpoint. However, the positive NIAGARA trial highlights that perioperative immunotherapy outcomes may differ across regimens.
The contrast with NIAGARA highlights the complexity of perioperative immunotherapy, reminding us that negative trials can be just as informative as positive studies in guiding future research and clinical practice.
Saturday 24th October
1. Personalised mRNA vaccine in resected melanoma
In Phase III INTerpath-001, 1,137 patients with resected stage IIB–IV melanoma received pembrolizumab with or without intismeran autogene, a personalised mRNA vaccine. The primary endpoint, 2-year recurrence-free survival (RFS), was significantly improved: 82.2% vs 70.0%. The key secondary endpoint, distant metastasis-free survival, also showed significant improvement, and overall survival data remain immature.
The result is encouraging and may extend personalised vaccination into adjuvant melanoma care. Whether the recurrence benefit translates into longer survival remains an important question.
2. Maintenance treatment in extensive-stage SCLC
DeLLphi-305 tested tarlatamab with durvalumab vs. durvalumab alone as first-line maintenance for patients whose extensive-stage SCLC had not progressed on durvalumab and platinum–etoposide.
The interim analysis demonstrated notable benefits across both primary and secondary endpoints, with median OS extending to 21.1 vs. 12.7 months and median PFS increasing to 7.4 vs. 1.9 months.
If confirmed with longer follow-up, these findings could elevate maintenance therapy from a routine continuation decision to a pivotal treatment opportunity, with the potential to meaningfully extend survival for patients.
3. EGFR/c-MET ADC: early activity in NSCLC
In the Phase I HS-20122 study, an EGFR/c-MET ADC demonstrated encouraging activity in patients with EGFR-mutant NSCLC. Across 106 response-evaluable patients, the ORR was 55.7%, increasing to 61.3% at the 6 mg/kg dose level, with a 6-month PFS rate of 75.3%.
The findings provide an early signal for the EGFR/c-MET ADC class, but the next challenge will be demonstrating whether this activity can translate into a differentiated treatment option in an increasingly crowded post-EGFR landscape.
Sunday 25th October
1. GSK AZUR-1: organ preservation in rectal cancer
Phase II AZUR-1 evaluated dostarlimab in previously untreated stage II/III MSI-H/dMMR locally advanced rectal cancer. An exploratory complete response (CR) rate of 76% (110/144) was reported, including 98 patients (68%) who achieved an investigator-assessed clinical CR lasting at least 12 months without surgery, while 12 had a pathological CR after surgery.
The primary endpoint, cCR12 by independent central review, remains immature: 47% (54/116) had met it, while 38 others had not yet reached the 12-month assessment.
The result is an important organ-preservation signal, but the 76% figure is not the primary-endpoint rate or the proportion who avoided surgery. A key adoption question is whether clinicians will be confident selecting and monitoring patients for non-operative management. Note the study was single-arm, without a comparator.
2. Biliary tract cancer: a first-line head-to-head result
In first-line advanced biliary tract cancer, Phase III HARMONi-GI1 demonstrated improvements in both overall survival and disease control for ivonescimab plus chemotherapy vs. durvalumab plus chemotherapy. At interim analysis, mOS reached 14.9 vs. 12.1 months, while mPFS was extended from 5.8 to 8.4 months.
By demonstrating benefit against an established regimen, there could be a new benchmark for first-line treatment. Confirmation across diverse patient populations will be important to understand its broader applicability. The study also reflects the growing contribution of China-led research, a theme seen throughout ESMO 2026 and one that is likely to continue.
3. SAFFRON: targeting MET-driven resistance after osimertinib
In patients with EGFR-mutated advanced NSCLC and MET overexpression and/or amplification following progression on osimertinib, Phase III SAFFRON compared osimertinib plus savolitinib with platinum-pemetrexed. The study met its primary endpoint, with mPFS improving from 5.4 to 7.6 months, and mOS also extended from 12.9 to 17.8 months.
The results strengthen the case for MET testing after osimertinib, supporting a biomarker-led alternative to chemotherapy for this patient group. It will be important to understand where this combination fits in the treatment sequence to enable adoption.
Monday 26th October
1. Kisqali’s benefit remained evident years after treatment ended
In NATALEE, adjuvant Kisqali (ribociclib) plus endocrine therapy improved six-year OS vs. endocrine therapy alone in high-risk HR+/HER2- early breast cancer: 91.9% vs. 89.7% (HR 0.81). The absolute invasive disease-free survival (iDFS) benefit was 5.3 percentage points. Participants had been off Kisqali for a median of 38 months and had completed the planned endocrine therapy period.
This is relevant because a finite adjuvant course may have value beyond the years on treatment, making the longer-term benefit meaningful when weighing the treatment commitment against an absolute OS difference of 2.1 percentage points.
2. Endometrial cancer treatment may become more specific to biology and treatment line
In 1L dMMR advanced or recurrent disease, KEYNOTE-C93 improved mPFS vs. chemotherapy (38.2 vs. 8.4 months), although OS did not meet the pre-specified significance threshold. In previously treated disease, TroFuse-005 improved mPFS and mOS with sacituzumab tirumotecan vs. physician’s-choice chemotherapy: 7.2 vs. 3.9 months and 19.0 vs. 12.1 months.
Together, these studies highlight an increasingly stratified endometrial cancer landscape, where treatment decisions are becoming more dependent on biomarker status and prior therapy. The challenge now will be translating this growing complexity into clear treatment pathways.
3. MOIO leaves 12-week IO dosing unproven
Among patients with advanced or metastatic cancer whose disease was responding to treatment, MOIO compared standard dosing with dosing every 12 weeks. The interim analysis did not establish PFS non-inferiority, and an OS imbalance led to early stopping, although definitive inferiority was not established.
The lesson here is that de-intensification needs to earn its place: reducing treatment burden is valuable only if disease control is maintained, and these results do not support assuming that extended dosing intervals can achieve equivalent outcomes.
Want to discuss the latest shifts in oncology?
For more information, please contact:
Pam Hallworth- [email protected]
