The LEAP-010 trial showed a combination therapy improved tumor response and progression-free survival but failed to improve overall survival, the ultimate measure of benefit. This highlights the risk of relying on surrogate endpoints, which can be misleading, especially when a treatment adds significant toxicity.
In the LEAP-010 trial, the combination arm's higher efficacy was offset by significantly greater toxicity (67% vs 38% severe adverse events). This increased treatment burden likely limited sustained therapy and prevented patients from receiving subsequent treatments, ultimately nullifying any survival benefit from improved tumor response.
The LEAP-010 trial excluded patients with vascular involvement due to the drug's bleeding risk. This is a common characteristic in real-world head and neck cancer patients, especially post-radiation. This discrepancy means that even if the drug combination had been successful, its applicability in routine clinical practice would be severely limited.