Combined Immune Checkpoint Blockade and Helixor® Therapy in Oncology: Real-World Tolerability and Subgroup Survival (ESMO GROW)

Real-world data (RWD) play a crucial role in identifying key subgroups and assessing multimodal oncology therapies, including integrative and palliative care. Immune checkpoint blockade (ICB) has improved survival, and its combination with complementary therapies like <i>Viscum album</i> L. extracts (VA) may enhance outcomes. This RWD study, based on the Network Oncology registry and ESMO-GROW guidelines, analyzed oncological patients receiving PD-1/PD-L1 inhibitors alone or with Helixor^® VA (HVA) extracts. Primary and secondary objectives were tolerability and overall survival. Statistical analyses included Kaplan-Meier survival curves and Cox regression. Among 405 cancer patients, 344 received ICB alone (CTRL) and 61 received ICB + HVA (COMB). Lung cancer was predominant (78.6%). Adverse event-related discontinuation was lower in COMB (4.9% vs. 6.4%, <i>p</i> = 0.25). In non-small cell lung cancer (NSCLC) patients, the 3-year survival rate was significantly higher in COMB (34.3% vs. 17.2%, <i>p</i> = 0.02). In female NSCLC patients, COMB was significantly associated with a reduced death risk of 91.2% (aHR: 0.088; 95% CI: 0.009-0.783). Our RWD findings show the favorable tolerability of combinatorial ICB + HVA in several tumor entities and underscore its potential to improve survival in NSCLC particularly in female NSCLC patients, warranting further investigation.