NEW YORK--(BUSINESS WIRE)--RGENIX, Inc., a clinical stage biopharmaceutical company developing first-in-class small molecule and antibody cancer therapeutics, announced today it is presenting data showing clinical activity in patients with advanced colorectal (CRC) tumors from a clinical trial of RGX-202, a first-in-class small molecule that inhibits a novel cancer metabolism pathway involved in supplying energy to cancer cells. RGENIX’s abstract, “Phase 1 trial of RGX-202, a first-in-class oral inhibitor of the SLC6a8/CKB pathway, in patients with advanced gastrointestinal (GI) solid tumors”, is being presented by Dr. Johanna Bendell, Director of the Drug Development Unit at Sarah Cannon Research Center in Nashville, and clinical investigator and lead author on the study, as part of the 2020 American Society of Clinical Oncology Virtual Scientific Program during an oral abstract session available on demand starting on May 29.
RGX-202 is an oral small molecule inhibitor of the creatine transporter SLC6a8 that depletes intracellular phospho-creatine and ATP levels, leading to the death of cancer cells. The SLC6a8/CKB pathway was discovered using RGENIX’s proprietary miRNA-based target-discovery platform applied to KRAS mutant CRC. Due to increased metabolic demand, KRAS mutant tumors are highly susceptible to blockade of SLC6a8. In CKB-expressing (CKB+) pre-clinical models, RGX-202 treatment triggers tumor regressions across KRAS mutant subtypes. The ongoing Phase 1 trial of the compound is an escalation/expansion study of RGX-202 with or without FOLFIRI in patients with advanced GI tumors, and the trial will identify the maximum tolerated dose, or the dose at which multiple dose-limiting toxicities (DLTs) are not observed, and to determine the antitumor activity of the RGX-202.
As of April 29, 2020, 17 patients with advanced relapsed/refractory gastrointestinal cancers have been treated in 4 single agent dose escalation cohorts, with doses ranging from 600mg twice a day (BID) up to 3600mg BID. RGX-202 was well tolerated at all doses, with the majority (69%) of RGX-202-related adverse events (AEs) being grade 1 in severity with the most common AEs being nausea and vomiting. No DLTs were observed at any dose; notably, in the two highest cohorts, drug exposures predicted to be sufficient to inhibit human tumor growth from preclinical models were achieved along with concomitant pharmacodynamic effects.
10 patients were evaluable for response across all dose cohorts. Among the 5 evaluable patients with KRAS mutant CRC, 1 achieved a PR and 2 achieved stable disease, for an ORR of 20% and a disease control rate of 60%. Durable clinical benefit was observed in the highest dose cohort; a patient with KRAS G12V mutant CRC had a confirmed partial response of 40 weeks duration, and a patient with KRAS G13D mutant CRC experienced stable disease for 16 weeks. The ORR in all evaluable CRC patients - regardless of KRAS status - was 10% with a disease control rate (DCR) of 40%. A dose-escalation study assessing RGX-202 plus the chemotherapy regimen FOLFIRI is ongoing, with a planned expansion cohort in CKB+ CRC.
Masoud Tavazoie, MD, PhD, and Chief Executive Officer of RGENIX, said, “Though RGX-202 is still in an early stage of development, the results obtained to date are exciting. The single agent safety and activity profile provide a foundation for further development of RGX-202, including in combination regimens. Importantly, the results further validate our target discovery approach, which has now yielded two first-in-class clinical compounds, RGX-104 and RGX-202, both with single agent activity against novel targets discovered using our RNA-based platform technology. We look forward to sharing additional data from our programs as they progress through clinical development.”
RGENIX, Inc., is a privately-held clinical-stage biopharmaceutical company focused on the discovery and development of novel cancer drugs that target key pathways in cancer progression. The company is pursuing several first-in-class drug candidates to treat cancers of high unmet need. RGENIX identifies novel cancer targets using a microRNA based target discovery platform originally developed by RGENIX’s scientific co-founders at The Rockefeller University and now exclusively licensed to RGENIX. The company brings together distinguished scientific founders, a seasoned Board, and a leadership team comprised of experienced drug developers. The company is funded by leading biotechnology investors, including Novo Holdings A/S, Sofinnova Partners, Lepu Holdings Limited, Oceanpine Capital, WuXi PharmaTech Healthcare Fund I, LP, Alexandria Venture Investments,LLC, and the Partnership Fund for New York City. For more information, please visit www.rgenix.com.
RGX-202 is a small molecule that inhibits a novel cancer metabolism pathway involved in supplying energy to cancer cells. The target of RGX-202, the SLC6a8/CKB pathway, is over-expressed in several prevalent cancer types, including KRAS mutant colorectal cancer. RGX-202 has demonstrated anti-tumor activity in preclinical studies, both as a single agent as well as in combination with standard-of-care therapies. In a Phase 1 dose escalation, RGX-202 demonstrated clinical activity as a single agent in the KRAS mutant CRC setting. A Phase 1b study assessing the safety and clinical activity of RGX-202 in combination with FOLFIRI is ongoing.