While Akiso's Harmony 6 trial in China showed a survival benefit for its PD-1/VEGF bispecific with chemotherapy, it doesn't resolve the key question of whether these impressive results from Chinese populations will translate to a global patient population.

With half its patients from Asia and only 13% from North America, the Destiny Breast 11 trial's results may not be fully generalizable to US patients. Differences in metabolism, healthcare systems, and side effect reporting across regions can impact outcomes, a key consideration when interpreting global trial data.

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.

China’s efficiency in early-stage clinical trials is not a threat but a global asset. It allows for faster generation of proof-of-concept data, which helps de-risk programs for all companies before they undertake expensive, global trials for FDA approval.

Despite strong efficacy data, the drug DV-Toripalimab scored lower than a competitor (2.5 vs 3.0). Experts attribute this confidence gap to its Phase 3 trial being conducted only in China, which raises generalizability concerns and reflects a lack of hands-on experience for Western physicians.

The STARGLO trial (glofitamab-gemox) showed a strong survival benefit in Asia-Pacific patients but not in the small North American cohort. This geographic discrepancy, with only 9% of patients from the US, was a key reason the FDA did not approve the combination, while European agencies did.

The FDA is requiring higher US patient enrollment in global trials to address concerns that results from predominantly non-US populations (e.g., Asia) may not be generalizable. This reflects worries about differences in prior standard-of-care treatments and potential pharmacogenomic variations affecting outcomes.

Even when trials like LITESPARK 022 and Keynote 564 use identical eligibility criteria, outdated staging systems result in patient populations with different underlying risks. This makes direct comparison of outcomes between trials, even for the same drug, an unfair and statistically flawed analysis that ignores the function of a control arm.

Even with positive results from two registrational Phase 3 trials, experts note a potential regulatory hurdle. The FDA has shown increasing concern over studies with a low proportion of patients from North America, a characteristic of these trials, potentially complicating an otherwise strong case for approval based on clinical merit.