The universal cancer peptide-based vaccination (UCPVax) induces a CD4+ T helper-1 response that is directed against telomerase by combining two carefully chosen helper peptides. In the phase Ib/IIa study, patients with metastatic non-small-cell lung cancer (NSCLC) were enrolled to evaluate the effectiveness, immunogenicity, and safety of a three-dose regimen.
Using a Bayesian-based phase Ib followed by phase IIa de-escalating design, patients with refractory NSCLC were given three doses of UCPVax (0.25 mg, 0.5 mg, and 1 mg) as part of their vaccination regimen. The 2 main endpoints were immunological response following the first 3 vaccination doses and dose-limiting toxicity. Overall survival (OS) and progression-free survival at 1 year were secondary end goals.
Over 95% of the 59 patients who got UCPVax had previously undergone 3 different types of systemic treatment. In 15 individuals treated in phase Ib, no dose-limiting harm was noted. There was a 1 mg maximum tolerable dosage. Phase IIa eligibility included 51 individuals. There was no difference between the 3 dosage levels regarding the specific CD4+ T helper 1 response elicited by the third and sixth doses of UCPVax in 56% and 87.2% of patients, respectively. About 21 (39%) of the patients had disease control (n = 20 had stable disease; n = 1 had a full response). The median OS was 9.7 months, with no discernible difference across dosage levels, and the 1-year OS was 34.1% (95% CI, 23.1 to 50.4). In immune responders (P = .015), the 1-year progression-free survival and median OS were 17.2% (95% CI, 7.8 to 38.3) and 11.6 months (95% CI, 9.7 to 16.7), respectively, while in nonresponders (P = .005), the figures were 4.5% (95% CI, 0.7 to 30.8) and 5.6 months (95% CI, 2.5 to 10).
UCPVax was highly immunogenic, safe, and had an intriguing 1-year OS rate in advanced NSCLC that had received a lot of pretreatment.