In Situ, Autologous Therapeutic Vaccination Against Solid Cancers With Intratumoral Hiltonol®

The purpose of this study is to evaluate the safety of sequential intratumoral (IT) plus intramuscular (IM) Polyinosinic-polycytidylic acid stabilized with polylysine and carboxymethylcellulose (poly-ICLC, Hiltonol®) for treatment of study subjects with accessible solid tumors, with or without checkpoint blockers. Enrolled study subjects will receive Poly-ICLC (Hiltonol®) treatment alone or in combination with anti-PD-1 (Nivolumab, Pembrolizumab or Cemiplimab) or anti-PD-L1 (Atezolizumab or Durvalumab) over 6 months as defined in study treatment described below. MRI or CT imaging will be done per SOC at screening, 3 and 6-month time points.