Abstract CT256: A pilot clinical study of VAL-413 (Orotecan®, oral irinotecan HCl) in patients with recurrent pediatric solid tumors

Abstract Intravenous irinotecan hydrochloride (IRN-IV) is approved for the treatment of adult colorectal cancer. IRN-IV is also widely used off-label for a range of adult and pediatric solid tumors including recurrent Ewing sarcoma, rhabdomyosarcoma, neuroblastoma, hepatoblastoma, Wilms tumor, gynecologic cancers, lung cancer and medulloblastoma. Recently, commercially available intravenous irinotecan has been administered orally (IRN-IVPO) in pediatric patients to improve convenience, reduce in-clinic time and overall cost of treatment. Unfortunately, the palatability of the intravenous preparation is poor, leading to reduced compliance especially in younger pediatric patients. Development of an advanced formulation to improve tolerability and patient compliance is an important unmet need. VAL-413 is a novel formulation developed to improve palatability of oral irinotecan. We will report on an ongoing Phase 1-2 first-in-human clinical trial of VAL-413, designed to test the hypothesis that VAL-413 improves palatability without significant pharmacokinetic differences from IRN-IVPO using intra-patient comparison of pharmacokinetic profiles. The evaluation of two dose levels will help to formally define a recommended dose for advanced clinical studies. Trial Design: Patients ≥ 1 year of age or ≤ 30 years of age with recurrent pediatric solid tumors and adequate bone marrow, renal and liver function, for whom irinotecan therapy is a treatment option, are eligible. Up to 20 eligible patients will receive VAL-413 90mg/m2/day or 110mg/m2/day using a standard 3 + 3 design. During the first cycle of treatment, each patient will receive four daily doses of VAL-413 and one daily dose of IRN-IVPO, together with five (5) days of concurrent temozolomide. Pharmacokinetic assessments will follow both VAL-413 and IRN-IVPO administration using a limited sampling strategy. During all subsequent cycles, only VAL-413 will be given with temozolomide in 5-day courses administered every 21 days. Up to 17 cycles of treatment may be administered on this study. Outcome Measures: Toxicity is assessed by NCI CCTCAEv5; tumor response is assessed by RECIST 1.1. A palatability survey instrument will assess palatability of VAL-413 vs. IRN-IVPO; and comparative intrapatient pharmacokinetics of irinotecan and its metabolites will be assessed in all patients. Citation Format: James Geller, Patrick Thompson, Javier Oesterheld, Dennis M. Brown, Jeffrey Bacha, Sarath Kanekal, Lorena Lopez, Markos Leggas, Neil Sankar, Noymi Yam, Lars M. Wagner. A pilot clinical study of VAL-413 (Orotecan®, oral irinotecan HCl) in patients with recurrent pediatric solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT256.