Eisai says no to HER2

Daiichi Sankyo/AstraZeneca's juggernaut Enhertu spawned a myriad copycats – OncologyPipeline lists 87 HER2-targeting ADCs currently in active development – but one company that won't follow this herd is Eisai. At least that's according to the UK liquid biopsy specialist Angle, which worked with Eisai on a HER2 assay that was used in an Eisai-sponsored phase 2 study of BlissBio's BB-1701. This molecule, which uses an eribulin payload, in contrast to Enhertu's more trendy topoisomerase 1 inhibitor, was originated by China's BlissBio, which in May 2023 struck a clinical trial collaboration with Eisai that included the option of a full strategic collaboration. This came as phase 1 data at that year's ASCO showed a 50% ORR among 26 HER2-positive solid tumour patients, but grade 4 adverse events of neurological symptom and sepsis. On the back of this Eisai started a phase 2 trial for which Angle provided its Parsortix-based HER2 assay. While this trial has yet to yield efficacy data, on Friday Angle revealed that Eisai had decided not to exercise the option, and returned rights to BlissBio. Angle is now seeking to work on its assay with BlissBio, which apparently intends to continue developing BB-1701.

Eisai's work on ADCs

Source: OncologyPipeline.