In a French phase Ib/IIa trial reported in the Journal of Clinical Oncology, Adotévi et al found that a therapeutic universal cancer peptide–based vaccine (UCPVax) induced specific CD4+ T helper–1 responses in many patients with refractory advanced non–small cell lung cancer (NSCLC), with responding patients appearing to derive benefit from treatment.
UCPVax is a novel therapeutic vaccine composed of two highly selected helper peptides designed to induce antitumor CD4+ T helper–1 response.
About 60 patients with refractory disease were enrolled in the multicenter study between April 2016 and July 2021. Treatment consisted of vaccine doses of 0.25 mg, 0.5 mg, or 1 mg on days 1, 8, 15, 29, 36, and 43, followed by a booster dose every 8 weeks for a maximum of 12 months. A total of 15 patients were enrolled in phase Ib, and 51 evaluable patients were treated in phase IIa; among the 51 patients, 15 received 0.25-mg doses, 16 received 0.5-mg doses, and 20 received 1-mg doses. A total of 95% of patients had received three prior lines of systemic therapy.
No dose-limiting toxicities were observed in phase Ib, with the maximum tolerated dose being established as 1 mg. Among the patients in phase IIa, the third and sixth dose of UCPVax induced specific CD4+ T helper–1 responses in 56% of 51 patients and 87.2% of 39 patients, respectively, with no significant differences observed among the three dose levels. After the third dose, a response was observed in 7 of 15 patients receiving 0.25 mg, 9 of 16 receiving 0.5 mg, and 13 of 20 receiving 1 mg. A response was observed among nearly all 18 patients assessed after receiving booster doses.
Disease control was observed in 21 patients (39%), consisting of stable disease in 20 and complete response in 1. Among all 51 patients, overall survival at 1 year was 34.1% (95% confidence interval [CI] = 23.1%–50.4%) and median overall survival was 9.7 months (95% CI = 6.7–12.6 months), with no significant differences observed among dose levels.
For immune responders vs nonresponders after three doses, 1-year progression-free survival was 17.2% (95% CI = 7.8%–38.3%) vs 4.5% (95% CI = 0.7%–30.8%, P = .015) and median overall survival was 11.6 months (95% CI = 9.7–16.7 months) vs 5.6 months (95% CI = 2.5–10 months, P = .005). Overall survival at 1 year was 47.5% (95% CI = 32.2%–70.0%) vs 18.2% (95% CI = 7.5%–44.1%).
The most common treatment-related adverse events were grade 1 or 2 injection site reactions (58.5%), flu-like syndrome (16.1%), and gastrointestinal disorders (8.5%). Injection site reactions were more common with the 0.5 mg and 1 mg doses. One patient receiving 0.25 mg had grade 5 cerebral vasculitis lesions; the event was assessed as possibly related to treatment and considered unexpected.
The investigators concluded, “UCPVax was highly immunogenic and safe and provide[d an] interesting 1-year overall survival rate in heavily pretreated [patients with] advanced NSCLC.”
Olivier Adotévi, MD, PhD, of the Department of Medical Oncology, University Hospital of Besançon, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by the National Institute of Cancer, University Hospital of Besançon, Ligue contre le Cancer Grand Est, Cancéropôle Grand Est, and Invectys SA. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.