Summit, Akeso tout biliary cancer win for PD-1/VEGF in China—but details are pending

 

The Phase 3 readout is the first for ivonescimab beyond non-small cell lung cancer to show a significant overall survival benefit, according to Summit Therapeutics and China-based partner Akeso.

Summit Therapeutics and China-based partner Akeso are on a good run this summer with ivonescimab. After demonstrating its value in Western populations, the PD-1/VEGF–targeting bispecific antibody has bested AstraZeneca’s Imfinzi in a Phase 3 trial of biliary tract cancer in China.

In the study, ivonescimab plus chemotherapy demonstrated a “significant overall survival benefit” in first-line biliary tract cancer (BTC), meeting the HARMONi-GI1 trial’s primary endpoint, according to a Tuesday press release from Akeso.

The study, which consisted of 682 patients, also hit all key secondary endpoints of progression-free survival (PFS) and objective response rate (ORR). Akeso reported the results—without detailed data—after a pre-specified interim analysis conducted by an independent data monitoring committee.

Summit’s shares popped 15% in premarket trading Wednesday to around $15 dollars following the news.

Further data from HARMONi-GI1 will be presented at an upcoming international academic conference, as well as published in a peer-reviewed journal.

Imfinzi plus chemo is currently the internationally recognized “preferred first-line immunotherapy regimen” for biliary tract cancer, according to Akeso. HARMONi-GI1 is the first known Phase 3 study to demonstrate statistically significant positive overall survival in advanced BTC and show superiority versus an anti-PD1 plus chemo, Summit said its own announcement on Tuesday.

It is also the first Phase 3 readout for ivonescimab beyond non-small cell lung cancer to demonstrate a significant overall survival benefit, Summit noted.

Last month, the partners reported that a Western subgroup of patients in the Phase 3 HARMONi trial of ivonescimab in endothelial growth factor receptor (EGFR)-mutated NSCLC had a 24% lower risk of death compared to patients receiving standard of care after nearly two years. Trial participants in China saw a 26% reduction in risk of death at 32.5 months. This result was key for Summit, as it answered questions about the candidate’s ability to translate to Western populations.

Ivonescimab first burst onto the scene in 2024 when data from the Phase 3 HARMONi-2 trial conducted in China showed the drug was 49% more effective than Merck’s blockbuster Keytruda at reducing risk of disease progression or death.

The drug secured its third approval in China earlier this month when the country’s National Medical Products Administration authorized it—along with chemo—for the first-line treatment of NSCLC. It wasn’t a clean win, however, as new data on the drug’s label showed degradation of PFS in the Phase 3 HARMONi-6 trial that supported the approval.

Leerink Partners at the time expressed concern that the ongoing HARMONi-3 trial intended to support an accelerated approval in the U.S. will not show a “substantial benefit” when the final analysis is revealed sometime this half.

Summit’s first moment of truth for the Western application of its prized PD-1/VEGF bispecific will come this fall, when the FDA is expected to render a decision for ivonescimab in NSCLC with EGFR mutations. The PDUFA date is November 14.

https://www.biospace.com/drug-development/summit-akeso-tout-biliary-cancer-win-for-pd-1-vegf-in-china-but-details-are-pending