Abstract LB-021: Intratumoral RNA-based TLR-7/-8 and RIG-I agonist CV8102 alone and in combination with anti-PD-1 in a Phase I dose-escalation and expansion trial in patients with advanced solid tumors (2019)

Abstract CV8102 comprises a single-stranded non-coding RNA complexed with a cationic peptide. It acts as an agonist to TLR-7/-8 and RIG-I (Ziegler 2018) to stimulate the innate and adaptive immune system. CV8102 was shown to induce an upregulation of inflammatory cytokines, chemokines and IFN-γ related genes at the injection site along with an activation of T, NK, NKT and migratory dendritic cells in the draining lymph nodes (Heidenreich 2015). Intratumoral (IT) CV8102 demonstrated dose-dependent anti-tumor activity and synergized with systemic PD-1 inhibition in preclinical models. Methods This Phase I study investigates IT CV8102 as single agent and in combination with systemic anti-PD-1 antibodies (as per product label). Patients (pts) with advanced inoperable melanoma (MEL), cutaneous/head and neck squamous cell or adenoid cystic carcinoma (cSCC, SCCHN, ACC) are eligible for single agent CV8102, pts with MEL and SCCHN who did not respond or slowly progressed on anti-PD-1 therapy are eligible for the combination. CV8102 is administered for up to 8 IT injections into a single accessible tumor lesion over a 12-week period. A Bayesian logistic regression model with overdose control is used for the dose escalation parts. Response is assessed by RECIST 1.1/irRECIST (injected and non-injected target lesions). Pre- and on-treatment samples are collected for biomarker analyses. Results A total of 20 pts have been treated with either CV8102 alone (N=15: 6 MEL, 2 SCCHN, 5 ACC, 2 cSCC) or CV8102 in combination with anti-PD-1 (N=5: 4 MEL, 1 SCCHN). Dose cohorts with doses up to 150 µg (CV8102 alone) and 100µg (CV8102+anti-PD-1) have been completed. Most common AEs were mild to moderate flu-like symptoms and injection site reactions. No dose limiting toxicities (DLT) were observed during the DLT period of the first two weeks of treatment. 12 pts treated with CV8102 alone were evaluable for response assessment. 1 MEL pt treated at 150µg experienced a complete regression of injected and non-injected lesions. This patient also experienced a marked increase of IL-6 and CRP at 6 and 24 hours after the first injection, respectively. 7 pts achieved stable disease, with two pts treated at 100 µg (SCCHN pt) and 200µg (MEL pt who had developed acquired resistance to previous anti-PD-1 therapy) showing regression of non-injected lymph node lesions. Dose escalation parts are continuing, updated safety and efficacy results will be presented. Conclusion Intratumoral single agent CV8102 appears well tolerated and showed preliminary evidence of clinical efficacy with shrinkage of injected and non-injected lesions. Citation Format: Thomas Eigentler, Juergen Krauss, Jutta Schreiber, Carsten Weishaupt, Patrick Terheyden, Lucie Heinzerling, Peter Mohr, Benjamin Weide, Ralf Gutzmer, Juergen C. Becker, Felix Kiecker, Angelika Daehling, Fatma Funkner, Regina Heidenreich, Sarah-Katharina Kays, Ute Klinkhardt, Birgit Scheel, Oliver Schoenborn-Kellenberger, Tobias Seibel, Claudia Stosnach, Tanja Strack, Ulrike Gnad-Vogt. Intratumoral RNA-based TLR-7/-8 and RIG-I agonist CV8102 alone and in combination with anti-PD-1 in a Phase I dose-escalation and expansion trial in patients with advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-021.