MVX-ONCO-1 Vaccine May Prolong Survival in Head and Neck Cancer

A personalized cancer vaccine called MVX-ONCO-1 may prolong survival in patients with recurrent or metastatic head and neck cancer, according to research presented at the ESMO Congress 2023.

The goal with MVX-ONCO-1 is targeted delivery of granulocyte macrophage colony-stimulating factor (GM-CSF), explained study presenter Nicolas Mach, MD, of Geneva University Hospital in Switzerland.

MVX-ONCO-1 consists of irradiated tumor cells from the patient and an encapsulated cell line genetically modified to produce GM-CSF.

Dr Mach and colleagues tested MVX-ONCO-1 in the phase 2a SAKK 11/16 trial (ClinicalTrials.gov Identifier: NCT02999646). The trial included 16 patients who had recurrent or metastatic head and neck squamous cell carcinoma that progressed after 1 or more lines of systemic therapy.

The patients’ median age was 59 (range, 42-76) years, and all but 1 patient were men. Five patients had received 1 prior line of therapy, 5 had received 2 prior lines, and 6 had received more than 2. Most patients (87%) had received immune checkpoint inhibitor therapy.

Patients received 6 subcutaneous vaccinations of MVX-ONCO-1 over 8 weeks. The primary endpoint was overall survival (OS) at 26 weeks, with a goal of at least 50% of patients being alive at that time point, Dr Mach said.

Enrollment was closed early because the primary endpoint was met ahead of schedule. Eleven of 16 patients were still alive at 6 months.

At a minimum follow-up of 11 months, the median OS was 11.4 months. The 1-year OS rate was 49.2%, and the 2-year OS rate was 31.6%. These OS results compare favorably to OS results seen with second-line immune checkpoint inhibitors, Dr Mach noted.

Delayed-type hypersensitivity (DTH) following vaccination seemed to play a role in survival, Dr Mach said. The median OS was 443 days in DTH-positive patients and 162 days in DTH-negative patients.

“[A]ll the patients that are able to mount DTH positivity upon vaccination are alive at 12 months, compared to only a very small fraction of them that did not mount an immune response,” Dr Mach said.

The best clinical responses after vaccination included an ongoing complete response in a patient with nivolumab-refractory disease, a partial response in a patient with nivolumab-refractory disease, 10 cases of stable disease, and 4 cases of disease progression.

Treatment-related adverse events (AEs) occurred in 25.1% of patients, and all were grade 1-2. Vaccination-site AEs occurred in 43.7% of patients, and all were grade 1-2.

“MVX-ONCO-01 may be the first cancer vaccine associated with prolonged survival in advanced chemo- and immune checkpoint inhibitor-refractory metastatic head and neck squamous cell carcinoma given as a monotherapy with no maintenance,” Dr Mach said.

He added that a future trial will compare first-line MVX-ONCO-01 vaccination plus immune checkpoint inhibitor therapy to first-line pembrolizumab.

Disclosures: This research was partly supported by MaxiVAX. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

Reference

Mach N, Fernandez E, Vernet R, et al. SAKK 11/16, a phase IIa trial evaluating overall survival (OS) for recurrent/metastatic head & neck squamous cell carcinoma (RMHNSCC) patients (pts) progressing after ≥ 1 line of systemic therapy, treated with MVX-ONCO-1, a novel, first in class cell encapsulation-based immunotherapy. Presented at ESMO Congress 2023. Oct. 20-24, 2023. Madrid, Spain. Abstract LBA46.

This article originally appeared on Cancer Therapy Advisor