Abstract A086: Early clinical trial results for 4-demethyl-4-cholesteryloxycarbonylpenclomedine (DM-CHOC-PEN) in adolescents and young adults (AYA) with cancers

Abstract Background: 4-Demethyl-4-cholesteryloxycarbonylpenclomedine (DM-CHOC-PEN) is a poly-chlorinated pyridine cholesteryl carbonate with a MOA via bis-alkylation of DNA @ N7-guanine and N4-cytosine that has completed phase I and II trials in adult subjects with cancer that had +/- CNS involvement (AACR #1185, 2013; AACR #CT 129, 2017). The aims were to assess clinical responses, monitor toxicities/safety, and confirm MTDs for IV administered DM-CHOC-PEN (IND 68,876). We report here responses and toxicities seen in a phase I DM-CHOC-PEN trial with AYA subjects who have cancer (some of whom had CNS involvement). Subjects and Methods: DM-CHOC-PEN was administered as a 3-hr IV infusion once every 21 days to subjects with advanced cancer in escalating doses from 39 - 98.7 mg/m2. The dosing schedule accounted for the liver toxicities seen in the adult phase I trial and was 2-tiered: for subjects with liver involvement, the cutoff was 85.8 mg/m2 and for subjects with normal liver function was 98.7 mg/m2. Results: Twelve (12) AYA subjects have been treated to date (with or without CNS involvement). The common tumor types treated were oligoastrocytoma, astrocytoma, GBM; leukemia (ALL), lymphoma (NHL), melanoma, breast, and lung cancers (NSCL). Most subjects (9) had CNS involvement. The drug was well tolerated; the most common adverse effects were fatigue (17%). No neuro/cognitive, liver dysfunction, hematologic, cardiac, renal, or GI toxicities were observed. PK modeling revealed that AUCs were parallel for all dose levels (39-98.7 mg/m2). The Cmax for DM-CHOC-PEN and DM-PEN (4-demethylpenclomedine, a metabolite) were 3 and 24 hours, respectively for the AYA subjects, similar to what was seen for older adults. However, the drug and metabolite were still detectable in plasma and rbcs for 21 to 50 days in the AYA (15 - 39 yo) group vs. 3 to < 21 days (as observed in previously treated adult (>60 yo) subjects (AACR #1185, 2013). Differences in PK profiles between AYA and older adult subjects will be reviewed in depth. Three (3) of the AYA subjects (1 each with NSCLC, ALL, and astrocytoma involving the CNS) have responded with CR/PR (RECIST 1.1), improved QOL/PFS (Kaplan-Meier), and OS from 8 to 26+ mos. All subjects will be reviewed. Conclusion: DM-CHOC-PEN is safe in doses of 39 - 98.7 mg/m2 and has produced objective responses with manageable toxicities in AYA subjects with cancer involving the CNS. Complete data on subject responses and observed toxicities will be presented. We propose a 3-stage mechanism for drug entry into the CNS and into cancer cells via reversible binding with RBCs and then association with L-glutamine transport into cells. Supported by NCI/SBIR grants - R43/44CA132257 and R43CA203351A and NIH NIGMS 1 U54 GM104940. Citation Format: Lee Roy Morgan, Andrew H. Rodgers, Roy S. Weiner, Tallat Mahmood, Marcus L. Ware, Manish Bhandari, Philip Friedlander. Early clinical trial results for 4-demethyl-4-cholesteryloxycarbonylpenclomedine (DM-CHOC-PEN) in adolescents and young adults (AYA) with cancers [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A086.