Summit Therapeutics’ $500m upfront bet on Akeso’s PD-1 x VEGF bispecific, ivonescimab, is looking increasingly well placed, with the latter having reported a second Phase III win for the drug through a Chinese study – this time in frontline, advanced biliary tract cancer (BTC).
The late-stage success stems from the Akeso-run HARMONi-GI1 study (NCT06591520), which is currently pitting a combination of ivonescimab and chemotherapy against AstraZeneca’s Imfinzi (durvalumab) plus chemotherapy in patients with BTC across several centres in a single region of China. Currently, the standard of care (SoC) in BTC revolves around treatment with chemotherapy agents gemcitabine and cisplatin plus an immune checkpoint inhibitor like Imfinzi or MSD’s Keytruda (pembrolizumab).
According to the results of a pre-specified interim analysis, patients treated with the ivonescimab regimen experienced statistically significant improvements in overall survival (OS) compared with those treated with the Imfinzi combination – besting one of the current SoC options in BTC and meeting the trial’s primary endpoint.
On top of its favourable impact on OS, the ivonescimab-chemotherapy combination also met its key secondary endpoints by offering significant improvements to progression-free survival (PFS), while improving patient objective response rates (ORR).
The companies expect to debut detailed results from the HARMONi-GI1 study at an upcoming medical conference.
Ivonescimab’s widespread solid tumour programme
This Phase III result marks the first win for ivonescimab in a gastrointestinal oncology indication – potentially signalling its promise in solid tumour indications outside of its initial Chinese approval in non-small cell lung cancer (NSCLC). Ivonescimab licensor, Summit, is also vying for the drug’s approval in the US, with regulators currently mulling a decision on the drug’s future on the NSCLC market.
The drug’s success will be welcome news for Summit, which pledged up to $5bn to Akeso to secure the rights to ivonescimab in the US, Europe, Canada, Japan, Latin America, the Middle East and Africa back in 2022.
Since then, the company has initiated several global frontline programmes for the drug – including studies in various subsets of NSCLC, as well as head and neck squamous cell carcinoma (HNSCC) and colorectal cancer.
Akeso is also evaluating ivonescimab in several other solid tumour indications through mid-to-late-stage studies. This includes ovarian and triple negative breast cancer, as well as the most common form of liver cancer, hepatocellular carcinoma.
According to a consensus forecast from GlobalData, parent company of Clinical Trials Arena, ivonescimab will approach mega-blockbuster status in 2032 by bringing in more than $9bn in sales.
