Innovent revives its US checkpoint plan

The plan to get the anti-PD-1 MAb sintilimab approved in the US hit a terminal roadblock in 2022, but its originator, Innovent, hasn’t been put off. The Chinese group’s latest plan is to advance IBI363, a fusion protein that combines PD-1 activity with IL-2, and today this received the FDA’s fast-track designation. Of course, such an accolade says nothing about the project’s approvability in the US, and with Innovent primarily targeting melanoma the likeliest development pathway would seem to be to study it in post-checkpoint patients in the relapsed setting, and as part of a Keytruda or Opdivo combo in the front line. At an ESMO virtual plenary in June Innovent reported a 17% ORR among 300 evaluable patients with various cancers given IBI363 ≥0.1mg/kg in a phase 1 trial. Mechanistically IBI363 is unusual; while most other IL-2 projects aim to avoid activity at the 2α subunit, to avoid activating T regulatory cells, IBI363 retains activity for IL-2Rα but has weakened binding to IL-2Rβ and IL-2Rγ, which Innovent says reduces toxicity. Innovent retains full rights to IBI363, so perhaps the FDA’s blessing will tempt a US partner.

Innovent's work on molecules with PD-(L)1 activity

Source: OncologyPipeline.