The American Society of Clinical Oncology (ASCO) Annual Meeting 2025, held from 30 May to 3 June, in Chicago, Illinois, showcased a sweeping array of oncological advancements, with 5,483 total presentations. This leading global forum delivered critical updates on emerging therapies, pivotal clinical trial outcomes, and evolving standards of care across a wide spectrum of cancer types.

AstraZeneca dominated the event in terms of share of voice, followed by Pfizer and Cellular Therapeutics. Breast cancer, lung cancer, multiple myeloma, and colorectal cancer emerged as the most heavily featured tumour types.

Breast cancer frontline therapies redefined

AstraZeneca and Daiichi Sankyo unveiled interim results from the DESTINY-Breast09 study, demonstrating that their antibody-drug conjugate (ADC) Enhertu (trastuzumab deruxtecan), combined with Perjeta (pertuzumab), led to a statistically significant and clinically meaningful improvement in progression-free survival (PFS). These results suggest the regimen may set a new first-line standard of care (SOC) for patients with HER2-positive metastatic breast cancer (mBC). Gilead and Merck & Co also made waves with their TROP-2–targeted ADC, Trodelvy (sacituzumab govitecan), in combination with the checkpoint inhibitor Keytruda (pembrolizumab). The combination showed impressive PFS improvements compared to Keytruda and chemotherapy in PD-L1–positive triple-negative breast cancer (TNBC), in the ASCENT-04/ KEYNOTE-D19 study, positioning it as a potential new frontline SOC. Gilead is doubling down on HER2-negative mBC, sponsoring multiple studies to expand Trodelvy’s footprint, including in the broader PD-L1–ineligible TNBC population.

Lung Cancer: Advancing Options in Hard-to-treat Subtypes

Johnson & Johnson’s Rybrevant (amivantamab) stood out in the MARIPOSA-2 trial, showing PFS improvements across various EGFR-mutant non-small cell lung cancer (NSCLC) resistance mechanisms—including MET-dependent, MET-independent, and unknown. These findings support its use after progression on EGFR tyrosine kinase inhibitors (TKIs). In contrast, Merck & Co and Daiichi Sankyo’s HER3-directed ADC, patritumab deruxtecan (HERTHENA-Lung02), did not meet expectations in the same treatment setting. Meanwhile, Amgen’s bispecific T-cell engager Imdelltra (tarlatamab) delivered a significant clinical benefit in the DELLphi-304 trial for patients with extensive-stage small cell lung cancer (ES-SCLC). With few effective options in this aggressive and historically treatment-refractory disease, Imdelltra is poised to shift the treatment landscape and become a preferred alternative to traditional chemotherapy.

Gastric Cancer Breakthroughs

AstraZeneca presented compelling results from two gastric/gastroesophageal junction (GC/GEJ) studies. DESTINY-Gastric04 reaffirmed the efficacy of Enhertu versus standard of care in HER2-positive tumuors—reinforcing its 2024 pan-tumour approval and supporting the case for a gastric-specific indication to drive further adoption.

Meanwhile, the MATTERHORN trial offered encouraging—though still immature—perioperative data for Imfinzi (durvalumab) in resectable GC/GEJ cancer. This contrasts sharply with Merck &Co’s KEYNOTE-585, which failed in a similar setting, setting the stage for a potential win for AstraZeneca in the PD-[L]1 space if final results hold up. ASCO 2025 underscored the rapid evolution of oncology treatment, as innovative therapies continue to displace legacy standards, especially in breast, lung, and gastric cancers. The meeting reflected a dynamic clinical and commercial landscape with intensified competition, broader biomarker targeting, and the promise of truly personalised