Investigational Immunotherapy Shows Survival Benefit in Advanced Squamous Lung Cancer
In the phase III PRESERVE-003 trial, the anti-CTLA-4 agent gotistobart improved median overall survival to 18.5 months versus 10 months with docetaxel in patients with metastatic squamous non-small cell lung cancer who had progressed on prior therapies. The 44% reduction in death risk was reported at the World Conference on Lung Cancer. The drug is designed to deplete regulatory T cells in the tumor microenvironment and may offer a chemo-free option.
The PRESERVE-003 trial enrolled 217 patients across centers in the U.S., Australia, China, Korea, and the U.K., with 91 classified as having squamous histology. One treatment arm testing a 3 mg/kg dose was discontinued early on the recommendation of the Data Monitoring Committee, leaving 87 squamous patients randomized between the 6 mg/kg gotistobart regimen and docetaxel. Most participants were men, Asian, and former smokers, with roughly a quarter from the U.S.
Gotistobart's mechanism differs from standard checkpoint blockade by selectively depleting regulatory T cells within the tumor microenvironment rather than broadly activating immune responses, which the investigators suggest may limit immune-related side effects. BioNTech has received both fast track and orphan drug designations from the FDA for this agent. Notably, progression-free survival was nearly identical between arms, yet overall survival diverged substantially, suggesting the benefit may emerge after treatment concludes.
If validated in later stages of the trial, this therapy could meaningfully expand options for squamous NSCLC patients who progress after standard treatments, a group with few targetable mutations and limited alternatives beyond docetaxel. The survival improvement of roughly eight months may represent a substantial clinical gain, though the modest response rate and similar progression-free survival indicate the benefit may be limited to certain patients. Regulatory approval, pricing, and confirmatory data will ultimately determine how widely this treatment becomes available.