Summit's Dual-Acting Drug Shows Promise in Lung Cancer Trial, Sparking Industry Excitement and Debate

Ivonescimab Outperforms Tevimbra in Chinese Study

Summit Therapeutics and Akeso's dual-acting lung cancer drug ivonescimab has demonstrated significant efficacy in a closely watched Phase 3 trial, potentially reshaping first-line treatment regimens for advanced non-small cell lung cancer (NSCLC). The HARMONi-6 trial, conducted in Chinese patients, showed that ivonescimab combined with chemotherapy significantly delayed disease progression compared to the immunotherapy Tevimbra and chemotherapy.

The trial results, presented at the European Society for Medical Oncology meeting in Berlin, revealed that the ivonescimab-chemo combination reduced the risk of progression by 40% compared to the Tevimbra-based regimen. Patients receiving ivonescimab lived a median of 11 months before disease progression, compared to seven months for those on Tevimbra.

Notably, the benefit was observed regardless of patients' PD-L1 protein status, a key biomarker for immunotherapy response. The side effect profile was similar between the two regimens, although ivonescimab-treated patients experienced a higher incidence of certain severe side effects related to VEGF-targeting treatment, such as hypertension and kidney damage markers.

Industry Implications and Investor Reactions

The positive results from the HARMONi-6 trial have intensified interest in ivonescimab and its drug class, which simultaneously blocks the immune checkpoint PD-1 and the blood vessel-building protein VEGF. This dual mechanism of action has sparked heavy investment in similar therapies, as the pharmaceutical industry seeks to improve upon existing immunotherapy options.

Wall Street analysts have expressed mixed reactions to the data. Some view the results as exceeding expectations, particularly given the statistically significant benefit observed at an early data check. These analysts suggest that the positive outcome bodes well for the ongoing global HARMONi-3 trial, which compares ivonescimab and chemotherapy to the current standard of care, Merck & Co.'s Keytruda with chemotherapy.

However, other analysts remain skeptical. Jefferies analyst Akash Tewari noted a shrinking difference in progression-free survival past the median checkpoint, suggesting that ivonescimab may not ultimately improve overall survival rates. Tewari commented, "We're not convinced monotherapy/chemo combo datasets will show a practice-changing benefit" on patient survival.

The market response to the news was reflected in Summit's share price, which fell 5% in Monday morning trading. This decline came alongside the release of Summit's third-quarter results, which revealed significant spending and reduced cash holdings. As of September 30, the company reported cash holdings of $239 million, having spent $173 million so far this year. Leerink Partners analyst Daina Graybosch suggested that without a larger development partner, Summit may need to raise additional funds to support ongoing development efforts.