Akeso (9926.HK): BTC Ph3 Data at ESMO'26 Could Extend Ivonescimab Story Beyond Lung Cancer

Following the encouraging HARMONi-2 OS update (note) at WCLC'26, we expect ivonescimab's Ph3 BTC (biliary tract cancer) data from the HARMONi-GI1 trial, to be presented as a late-breaking abstract (LBA) at ESMO'26 on Oct. 25, to be an important catalyst and a potentially meaningful validation point for ivonescimab beyond NSCLC. Akeso has already reported that HARMONi-GI1 met the primary endpoint of OS in August, which is another H2H (head-to-head) Ph3 study of ivonescimab, where ivonescimab+chemo was tested against durvalumab+chemo (n=682), the SoC (standard of care) in 1L BTC. At ASCO'24, ivonescimab plus chemo demonstrated strong China Ph2 data in BTC, where mPFS and mOS were 8.5 and 16.8 months, respectively, in 22 patients with 13.8 months of median follow-up. Considering that in the Chinese extended cohort of TOPAZ-1, mPFS and mOS were only 4.7 and 9.1 months, respectively, we estimate the OS HR (hazard ratio) in HARMONi-GI1 could potentially hit 0.6 or below assuming linear OS cu