Phase 1b/2, open label, multicenter, study of intratumoral SD-101 in combination with pembrolizumab in anti-PD1 naïve & experienced metastatic melanoma patients.

• DOI: 10.1200/jco.2017.35.15_suppl.9550
• Publication Date: 2018-09-06T15:54:26Z
• Authors: Abraham C.F. Leung; Shivaani Kummar; Sanjiv S. Agarwala; John J. Nemunaitis; Rene Gonzalez; Joseph J. Drabick; Emmett V. Schmidt; Elliot Chartash; Biao Xing; Graeme Currie; Robert Janssen; Antoni Ribas
• Keywords: Chills; Pneumonitis; myalgia

9550 Background: SD-101 is a synthetic CpG-ODN agonist of TLR 9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting activate T cell anti-tumor responses. Pembro PD-1 inhibitor approved for the treatment metastatic melanoma. This study, MEL-01 (NCT02521870), assesses safety preliminary efficacy in combination with pembro stage IIIC-IV Methods: A modified 3+3 design was used dose escalation 1, 2, 4, 8 mg injected single tumor lesion Q1W x 4 then Q3W 7 (200 IV Q3W). Tumor responses were assessed per investigator using RECIST v1.1. Results: In phase Ib, 22 pts enrolled: median age 64 y/o, male 68%, white 82%, Stage IV/IIIc 86%/14%, LDH > 1 ULN 27%, ≥ 3 prior lines therapy 36%, anti-PD-1 naïve (n = 9) experienced 13). There has been no limiting toxicity (DLT) date. The most common (≥20%) treatment-related AEs (TRAEs) transient low-grade fatigue, myalgia, headache, chills injection site reactions. Grade TRAEs observed 59.1% (most common: myalgia 13.6% pain 13.6%). Immune-related occurred 2 pts. One had G2 pneumonitis on Day 23 resulting drug withdrawal other G3 hypophysitis (85 days after last treatment). No deaths occurred. Responses at all doses pts, both non-injected lesions. response seen With f/u 97 (max 382), ORR 66.7% patients best overall CR 22.2% 2), PR 44.4% 4), SD 11.1% 1), PD NE 1). pts: 7.7% 1) 38.5% 5). Conclusions: well tolerated demonstrates worsening expected toxicities each individual monotherapies. These interim data support enhanced activity adding naive melanoma as potential Additional follow up through May 15, 2017 will be presented. Clinical trial information: NCT02521870.