1137P - Immuno-Chemoablation of Metastatic Melanoma with Intralesional Rose Bengal

Abstract

ABSTRACT Intralesional rose bengal (PV-10) is being investigated for treatment of solid tumors, where it may elicit selective chemoablation of injected lesions and a tumor-specific, immune-mediated bystander response in untreated bystander lesions. In phase 1 testing in 20 subjects with AJCC Stage III-IV melanoma, single-dose treatment with PV-10 was well tolerated, producing a durable objective response (OR) at 12-24 weeks in 40% of subjects (20% CR + 20% PR by modified RECIST) and locoregional disease control (CR + PR + SD) in 75% of subjects; 15% of subjects achieved an OR in bystander lesions, which strongly correlated with response of their injected lesions. Phase 2 testing in 80 subjects with Stage III-IV metastatic melanoma (median age 70.0 yrs, range 33-97) commenced at 7 centers in Australia and the USA in October 2007 with final clinical evaluation completed in May 2010 (Clinical Trials ID NCT00521053). In this study, subjects could receive up to four courses of PV-10 to up to 20 cutaneous or subcutaneous lesions (median 2 courses, range 1-4). Preliminary study data was presented at SMR 2010 in Sydney, Australia, and showed that treatments were well tolerated, with adverse events predominantly mild to moderate, locoregional and transient, with no grade 4 or 5 AEs attributed to PV-10. Preliminary evaluation also showed robust response, with 24% of subjects achieving a CR, 25% PR and 22% SD of their target lesions. Additionally, 24% of 38 subjects with evaluable, untreated bystander lesions achieved CR in their bystander lesions, along with 13% PR and 18% SD. As observed in phase 1, response of bystander lesions strongly correlated with response of injected lesions. Final efficacy data will be presented, including response rate and time-to-event (progression free survival and overall survival). These data demonstrate that the safety and efficacy profile of PV-10 compares favorably with available and emerging treatment options for this patient population, and serve as the basis for phase 3 testing of PV-10 in Stage III patients with recurrent, in-transit or satellite metastases. A randomized controlled trial to assess PFS against standard care is expected to commence in the second half of 2012 at centers in Australia, the USA and the EU. Disclosure S.S. Agarwala: Provectus Pharmaceuticals: advisory board, corporate-sponsored research. J.F. Thompson: Provectus Pharmaceuticals: advisory board, corporate-sponsored research. B.M. Smithers: Provectus Pharmaceuticals: corporate-sponsored research. M. Ross: Provectus Pharmaceuticals: advisory board, corporate-sponsored research. B.J. Coventry: Provectus Pharmaceuticals: corporate-sponsored research. D.R. Minor: Provectus Pharmaceuticals: corporate-sponsored research. C.R. Scoggins: Provectus Pharmaceuticals: advisory board, corporate-sponsored research. E. Wachter: Employee of sponsoring company, stock holder