Summit and Akeso's Ivonescimab Gains Chinese Approval Amid US Uncertainty

Chinese Regulators Green-Light PD-1/VEGF Immunotherapy

Summit Therapeutics and Akeso's novel PD-1/VEGF bispecific antibody, ivonescimab, has received approval from China's National Medical Products Administration for first-line treatment of certain non-small cell lung cancer (NSCLC) patients. This milestone marks a significant advancement for the closely watched immunotherapy, positioning it as a potential challenger to Merck's dominant Keytruda in the lucrative NSCLC market.

The approval is based on data from clinical trials conducted exclusively in China, raising questions about the therapy's prospects in Western markets. Summit Therapeutics, which holds the rights to ivonescimab in the U.S., Canada, Europe, and Japan, faces the challenge of translating this success into regulatory approval beyond China's borders.

Mixed Signals from HARMONi-2 Trial Data

Interim results from the HARMONi-2 trial have yielded conflicting interpretations among industry analysts. The study, comparing ivonescimab to Keytruda in PD-L1-positive NSCLC patients, failed to demonstrate a statistically significant improvement in overall survival (OS) at 39% data maturity. This outcome has led some experts, including analysts at BMO Capital Markets, to question ivonescimab's ability to effectively challenge Keytruda's market dominance.

Conversely, Truist Securities analysts maintain a more optimistic outlook, suggesting that the final OS data, expected by year-end, could still prove favorable for ivonescimab. They argue that the current data provides an early glimpse into the therapy's Phase III performance and that the separation of OS curves is encouraging at this stage.

Regulatory Hurdles and Market Implications

The approval in China represents a victory for Akeso, the drug's developer, but Summit Therapeutics faces significant challenges in securing approval in Western markets. The company's stock value dropped by approximately one-third following the news, reflecting investor concerns about ivonescimab's global prospects.

Experts, including Christiana Bardon of MPM BioImpact, have highlighted the need for more diverse data and emphasized the importance of overall survival as a key metric for prescribing decisions. The lack of data from non-Chinese populations raises concerns about potential differences in genetics and cultural factors that could affect the drug's performance and safety profile in other regions.

To address these issues, Summit is currently conducting the global Phase III HARMONi-3 trial, which aims to provide the necessary data for a U.S. approval application. The outcome of this study will be crucial in determining ivonescimab's future in the global pharmaceutical market and its potential to challenge established therapies like Keytruda in the treatment of NSCLC.