OS data of the HIMALAYA trial in hepatocellular carcinoma

Prof Dr Timon Vandamme, a digestive oncologist at the University Hospital of Antwerp, discussed the six-year OS data from the HIMALAYA trial in hepatocellular carcinoma (HCC) that were presented as a poster during ESMO 2025. The HIMALAYA study is a landmark Phase III trial comparing durvalumab plus a single priming dose of tremelimumab—known as the STRIDE regimen—to sorafenib, which has been the long-standing standard of care in advanced liver cancer. Previous analyses had already established the superiority of STRIDE, and it has since become a standard first-line treatment in Belgium and many other countries.

The updated data presented this year provide valuable long-term outcomes, offering a clearer view of the durability of benefit with immunotherapy. Notably, the new dataset includes an extension cohort of Chinese patients, as none were enrolled in the original global trial. This addition helps to confirm the regimen’s consistency across ethnic and regional populations, demonstrating that the efficacy and safety observed previously are reproducible in a broader patient population.

In the pooled six-year analysis, the results continue to favour the STRIDE combination. The three-year OS rate was 31% with STRIDE compared to 21% with sorafenib, while the six-year OS rates were 17.1% versus 8.9%, respectively. These findings highlight a doubling of long-term survival with the dual immunotherapy approach. Importantly, these figures remain very close to those seen at five years (approximately 19% for STRIDE), confirming that patients who respond to STRIDE can achieve long-term disease control, with survival plateaus visible in the “tail of the curve.” This durability of response underscores the potential for long-term remission or functional cure in a subset of HCC patients—something previously unattainable with tyrosine kinase inhibitors like sorafenib.

The safety profile remains consistent with earlier reports. Most immune-related adverse events were manageable and in line with expectations for checkpoint inhibitors. In the Chinese subpopulation, the toxicity profile mirrored global results, with no new safety signals identified. The combination of a single tremelimumab priming dose with ongoing durvalumab maintenance appears to maintain efficacy while minimising cumulative toxicity, supporting its practical use in real-world settings.

Prof Van Damme emphasised that these long-term findings provide reassuring confirmation of both the efficacy and tolerability of the STRIDE regimen. The six-year outcomes reinforce what clinicians already observe in daily practice: that patients who benefit from this dual immunotherapy tend to experience prolonged, durable responses and maintain a good quality of life over time.