ASCO 2025: Key highlights

Anti-body drug conjugates (ADCs) took centre stage at this year's American Society of Clinical Oncology (ASCO) meeting in Chicago, Illinois. Credit: THOM LEACH / SCIENCE PHOTO LIBRARY / Getty Images

This year’s American Society of Clinical Oncology (ASCO) meeting featured significant trial readouts and related announcements from the biggest names in pharma.

Thousands of companies attending the world’s biggest cancer conference, which took place between 30 May and 3 June in Chicago, Illinois, shared trial data and other developments that give a glimpse into where the oncology space is headed.

Without a doubt, antibody drug conjugates (ADC) took centre stage at this year’s meeting, with encouraging readouts from pharma giants including AbbVie and Merck & Co (MSD).

The meeting also featured promising readouts on drug candidates for breast cancer, multiple myeloma (MML), lymphoma, and colorectal cancer (CRC).

Pharma Technology takes a look at some of the biggest stories that emerged from ASCO 2025.

At this year’s ASCO meeting, ADCs, cancer-targeting therapies that combine monoclonal antibodies with the cell-killing power of cytotoxic drugs, took centre stage.

According to GlobalData analysis, the ADC market is forecast to exceed $45bn by 2030, up from $8.6bn in 2023.

Merck KGaA presented data from its ongoing PROCEADE-CRC-01 study (NCT05464030) investigating the dose, safety and tolerability of intravenous (IV) ADC precemtabart tocentecan in around 200 patients with metastatic colorectal cancer (mCRC).

Data for the ADC, an anti-CEACAMS that acts by selectively delivering a cytotoxic topoisomerase 1 inhibitor payload (exatecan), revealed a median duration of response (DoR) in mCRC trial patients of 23.3 weeks, with nearly 60% of patients having had six cycles of treatment. The median progression free survival (PFS) was 6.9 months, with a 72% disease control rate at week 12.

Scott Kopetz, one of the ongoing trial’s investigators from the MD Anderson Cancer Center commented: “This ADC compares favourably versus the current monotherapy in third-plus line treated mCRC where response rates are in the single digits. Therefore, we think this represents a very active regimen, even in patients that have been previously treated with irinotecan as we’re seeing in this population.”

Meanwhile, AbbVie presented positive Phase I trial (NCT05029882) data for Temab-A (telisotuzumab adizutecan), an ADC for treating patients with lung cancer.

AbbVie’s candidate achieved an overall response rate (ORR) of 63% in patients with advanced EGFR (epidermal growth factor receptor)-mutated, non-squamous (NSQ) non-small cell lung cancer (NSCLC). The drug has already demonstrated positive data in patients with wildtype EGFR.

Further data from the Phase I Temab-A trial revealed that the 41 patients enrolled demonstrated a median duration of response at 9.8 months and a median progression-free survival of 10.9 months.

Commenting on the trial results, Dr. Nivedita Aanur, NSCLC clinical lead at AbbVie, told Pharmaceutical Technology: “The data demonstrates a manageable safety profile, promising anti-tumour activity … and are supportive of further exploration of this novel ADC in this setting.”

Also at ASCO25, Merck & Co’s presented promising data for Zilovertamab vedotin, an ADC developed to treat diffuse large B-cell lymphoma (DLBCL) that targets ROR1, which is a transmembrane protein overexpressed in multiple haematologic malignancies, from an ongoing Phase II/III waveLINE-003 study (NCT05139017).

When administered in combination with standard of care, rituximab and gemcitabine-oxaliplatin (R-GemOx), the candidate achieved an objective response rate (ORR) of 56.3%.

With Zilovertamab vedotin, Merck & Co is looking to compete with ADC Therapeutics’ Zynlonta (loncastuximab tesirine-lpyl), which is the only ADC approved by the US Food and Drug Administration (FDA) for DLBCL. In ADC Therapeutics’ Phase II LOTIS-2 trial, Zynlonta – administered as a monotherapy – produced an ORR of 48.3%, with ORR data for Merck & Co’s candidate outdoing Zynlonta’s ORR by 8%.

Also at the conference, data was presented from the ASCENT-04/KEYNOTE-D19 study (NCT05382286) investigating Gilead’s Trodelvy, a trophoblast cell surface antigen 2 (TROP 2)-directed ADC in combination with Keytruda (pembrolizumab), versus standard-of-care (SOC) chemotherapy plus pembrolizumab in patients with PD-L1-positive (CPS ≥10) metastatic triple-negative breast cancer (TNBC).

The data demonstrated an improvement in median progression-free survival (PFS), with 11.2 months observed in the ADC-immunotherapy combination arm compared to 7.8 months in the SOC arm, at a median follow-up of 14 months. According to GlobalData analysis, these findings support the expectation that Trodelvy combined with Keytruda will become the new SOC in PD-L1-positive TNBC, shifting the frontline treatment paradigm from chemoimmunotherapy to ADC-based immunotherapy – a growing trend across tumour types in the metastatic setting.

Beyond the justifiable buzz around ADCs, Johnson & Johnson (J&J presented data at ASCO25 demonstrating that its cell therapy Carvykti (ciltacabtagene autoleucel) improved survival for multiple myeloma patients regardless of their cytogenetic risk or prior lines of therapy.

Subgroup analysis of the Phase III CARTITUDE-4 trial (NCT04181827) showed Johnson & Johnson’s (J&J) Carvykti improved overall (OS) and progression-free survival (PFS) for relapsed or refractory multiple myeloma patients (r/r MM) compared to standard-of-care (SOC).

At a median follow-up of 33.6 months among the 419 enrolled patients, median PFS among those with extramedullary disease, a risk factor associated with poor prognosis, was found to be 13 months for Carvykti-treated patients versus for months for those given SOC.

Also at the conference, J&J reported data from a Phase I trial of its bispecific antibody, pasritamig, for metastatic castration-resistant prostate cancer (mCRPC).

Data showed that in the recommended Phase II doses (RP2D) group for the antibody – at 3.5mg, 18mg and 300mg intravenously, on day one, eight and 15, respectively -- 42.4% of subjects achieved a significant decrease in prostate-specific antigen levels, with a median radiographic progression-free survival of 7.9 months.

In head and neck cancer, Merus and Bicara presented trial readouts at ASCO, which appeared to close the case on who the market leader for therapies used in combination with Keytruda for this form of cancer would be.

Merus announced data from 43 evaluable patients who received the petosemtamab + Keytruda combination, confirming an overall response rate (ORR) of 63% (95% confidence interval [CI]: 49–75%), a median progression-free survival (PFS) of 9 months (95% CI: 5.2-12.9), and a 12-month overall survival (OS) of 79%. Bicara’s ficerafusp alfa + Keytruda combination posted an ORR of 53% (95% CI: 37–70%), a median PFS of 7.4 months (95% CI: 2.9–14.5%) and a 12-month OS of 61.5%.

According to GlobalData analysis, the market favours one of these two announcements above the other: between May 22 and May 23, Merus’ stock price increased 32% while Bicara’s plummeted 41%. Merus and Bicara are continuing the clinical development of their respective assets into Phase III in this space. However, ficerafusp alfa is going with a narrower patient population, excluding patients who are positive for human papillomavirus (HPV).

This year’s ASCO meeting also saw some significant development in prostate cancer tests. Researchers from the UK’s Institute of Cancer Research (ICR) and University College London (UCL) applied analysis of a prostate cancer test developed by ArteraAIby applying it to the more than 1,000 men who took part in the Stampede trial (NCT00268476), coordinated by the Medical Research Council (MRC) Clinical Trials Unit at UCL and funded by Cancer Research UK.

ArteraAI helped identify that 25% of men with high-risk prostate cancer from the Stampede trial who would most likely benefit from receiving abiraterone.

For those patients with biomarker-positive tumours, abiraterone cut the risk of death after five years from 17% to 9%.