692 COMMANDER-001: safety data from a phase I/II dose escalation/expansion study of SQZ-eAPC-HPV, a cell-based mRNA therapeutic cancer vaccine for HPV16+ solid tumors

BackgroundCancer vaccines aim to generate antigen-specific CD8+ T cell responses. However, their efficacy has been hampered by inefficient targeting of delivered antigens to the MHC-I complex. SQZ-eAPC-HPV is an autologous, HLA agnostic, PBMC cell vaccine targeting HPV16 viral oncoproteins, E6 and E7, using the Cell Squeeze® platform. This technology simultaneously delivers 5 mRNAs encoding for full length HPV16 E6 and E7 proteins, CD86, and membrane-bound (mb) IL-2 and mbIL-12 cytokines directly into the cytosol of peripheral blood mononuclear cells (PBMC) via temporary cell membrane disruption using a microfluidic chip, which results in increased MHC-I antigen.MethodsCOMMANDER-001 (NCT05357898) includes patients with advanced HPV16+ cancers progressing after standard therapy who have an ECOG of 0–1, proper organ function, and RECIST measurable lesion(s). After leukapheresis, the cell product is manufactured in 3 adverse events reported.ConclusionsSQZ-eAPC-HPV has been well tolerated across all dose escalation cohorts. Enrollment in Cohort 3 (5.0x106/kg) is ongoing. Recommended phase 2 dose is expected to be declared in 2023. The presentation will include safety, preliminary efficacy, and pharmacokinetic/pharmacodynamic data from a cut-off proximal to presentation.AcknowledgementsWe thank the patients, their families, and their caregivers for their time and their willingness to participate in this study. We also thank theinvestigators and the investigational site staff for their contributions to the study.Ethics ApprovalThe study was performed in accordance with ethical principles that originated in the Declaration of Helsinki consistent with the ICH/GCPand applicable regulatory