iTeos will secure $35m from GlaxoSmithKline (GSK) because it has reached its development-based milestone of treating the first patient in the Phase III trial of its TIGIT antibody belrestotug (EOS-448) and Jemperli (dostarlimab).
The pair teamed up in June 2021 to jointly develop and market EOS-448, a human IgG1 antibody binds to TIGIT or T cell immunoglobulin and ITIM domains. The Phase III study is comparing the Jemperli/belrestotug combination to placebo and Keytruda (pembrolizumab) in patients with non-small cell lung cancer (NSCLC).
As per the 2021 deal, the total payments – which cover research, development, and commercialisation milestones – could exceed $1.4bn. When the deal was announced, iTeos received $625m in upfront payments. Both companies will split profits in the US, and iTeos is eligible to receive royalty payments borne from the partnership outside the US.
The Phase III GALAXIES LUNG-301 trial (NCT06472076) is set to enrol 1,000 patients with first-line advanced, unresectable, or metastatic programmed death ligand 1 (PD-L1)-high NSCLC. The primary endpoints of the trial are progression-free survival and overall survival. Participants will be randomised at a 1:1 ratio to receive either an intravenous infusion of the belrestotug plus Jemperli regimen or placebo plus MSD’s PD-1 inhibitor Keytruda.
Belrestotug is also being evaluated in the Phase II GALAXIES Lung-201 trial (NCT05565378), which is enrolling 300 NSCLC patients. Data from the most recent interim analysis showed a clinically meaningful reduction at every dose of the combination tested when compared to monotherapy with Jemperli or Keytruda in the patients.
This Phase II data was revealed in May 2024, the same month that iTeos closed a $120m direct offering led by existing investors RA Capital Management and Boxer Capital.
According to a report on GlobalData’s Pharma Intelligence Center, the number of diagnosed NSCLC cases is set to increase from 1,097,467 cases in 2022 to 1,463,151 cases in 2032, in the eight major markets (US, UK, France, Germany, Italy, Spain, Japan, and Urban China).
GlobalData is the parent company of Pharmaceutical Technology.
In the announcement accompanying the trial milestone, iTeos’ CEO Michel Detheux said: “The decision to launch our first TIGIT:PD-1 doublet Phase III trial underscores our disciplined, data-driven investment approach and was informed by several promising preliminary clinical surrogates such as safety, ORR, and depth of response from the latest interim analysis in May 2024.”
