T-cell Epitopes Associated With Impaired Peptide Processing (TEIPP)- Targeting Immunotherapy in Patients With Relapsed Advanced Non Small Cell Lung Cancer (NSCLC)

Immunogenic tumors can be controlled by tumor-reactive Tcells either directly or after checkpoint blockade. In the end, most tumors will develop mechanisms to escape immune control. One of such a mechanism is formed by the functional impairment of the intracellular peptide transporter TAP1/TAP2 by mutation of downregulated expression. As a result the presentation of conventional T-cell epitopes in HLA class I is lost, and hence tumor-reactive CD8+ T-cells fail to recognize and kill tumor cells. This type of immune escape can occur in up to 50% of primary tumors and is increased in the metastatic lesions of such tumors. The presence of these TAP defects correlate with worse clinicopathological parameters and has been associated with loss of durable benefit to checkpoint inhibition. The unmet need, therefore, is the development of a therapy that can reinforce effective tumor-immunity to cancers displaying TAP-defects for which conventional therapeutic cancer vaccines and/or checkpoint blockade do not work. TEIPP therapy may fill this position by reinstalling an effective antitumor response to TAP-defective tumors thereby increasing the overall survival of patients failing first line therapy.

In this prospective, single arm, multicenter, open-label, phase I-II clinical study, HLA-A*0201-positive patients with NSCLC failing first line of treatment will be enrolled in 3 cohorts and one extension cohort of 6 patients (at the highest safe and tolerable dose) combined with a checkpoint inhibitor targeting PD-1/PD-L1 (CPI), to include 24 patients in total. The maximal total treatment duration is 9 weeks. The first 6 patients will be enrolled in cohort 1, the next 6 patients in cohort 2, the next 6 patients in cohort 3. The decision to start enrollment at the next dose level will be made by assessing the safety after 3 out of 6 patients at the previous dose level have completed vaccine therapy.

Patients will receive an off the shelf TEIPP24 vaccine mixed with Montanide ISA-51 adjuvant, which will be administered every three weeks for a period of three rounds of vaccination. Patient cohort 1 will be treated with TEIPP24 at a dose of 20ug of peptide, patients in cohort 2 with TEIPP24 at a dose of 40ug of peptide and patients in cohort 3 with TEIPP24 at a dose of 100ug of peptide. Patients in the extension cohort will receive the highest safest dose in combination with pembrolizumab (a CPI). Patients will receive three rounds of vaccination three weeks apart via one subcutaneous (SC) injection in a limb. The SC route of administration of TEIPP24 vaccine is dictated by the use of Montanide ISA51. Subsequently patients will be followed up to 1 year after the first vaccination.