RiboX Therapeutics Ltd. has announced that the U.S. Food and Drug Administration (FDA) has cleared its Investigational New Drug (IND) application for RXRG001, a first-in-class circular RNA therapy intended for the treatment of radiation-induced xerostomia (RIX) and hyposalivation. The clearance allows RiboX to proceed with a Phase I/IIa clinical trial (SPRINX-1 Study) to evaluate the safety and efficacy of RXRG001 in patients experiencing these debilitating side effects of head and neck cancer (HNC) radiation therapy.
Xerostomia and hyposalivation are common and distressing sequelae of radiation therapy in HNC patients, a patient population that is growing as HNC becomes the sixth most common malignancy worldwide. Radiation-induced damage to salivary glands results in decreased saliva secretion, leading to dry mouth, difficulty swallowing, impaired oral health, and reduced quality of life. With the last FDA approval for a xerostomia treatment occurring two decades ago and current treatments deemed ineffective, temporary, and costly by patients, there remains a significant unmet medical need for new therapeutic options.
RXRG001: A Novel Circular RNA Therapeutic
RXRG001 leverages circular RNA technology to address this unmet need. Circular RNA offers advantages over traditional mRNA therapies, including enhanced stability, reduced immunogenicity, and tunable protein expression. RXRG001 consists of a circular RNA encoding human aquaporin 1 (hAQP1), a water channel protein crucial for saliva production, encapsulated in lipid nanoparticles (LNPs). By restoring water permeability through hAQP1 overexpression, RXRG001 aims to alleviate dry mouth symptoms.
Preclinical studies have demonstrated a favorable risk-benefit profile for RXRG001. Notably, a single administration in animal models resulted in a significant and sustained increase in salivary flow lasting approximately four weeks.
Clinical Development and Future Implications
"RIX is a devastating life-long health issue for patients with HNC. Although radiation therapy improves patients’ survival, its damage to the salivary glands leads to an impaired quality of life of many cancer survivors," said Dr. Yizhen Xu, Chief Medical Officer of RiboX. "RXRG001 may offer a potential effective and sustained therapeutic option for RIX patients. We are excited to conduct clinical trials to further evaluate its efficacy and safety in patients."
Dr. Weiyi Zhang, Chief Executive Officer of RiboX, added, "The FDA’s clearance of the IND application for RXRG001 is an acknowledgment of our innovative capabilities, robust technology, and competitiveness in the field of circular RNA therapeutics. RiboX will advance the clinical development of RXRG001, continue leveraging the unique advantages of circular RNA technology in therapeutic applications, and introduce more pioneering treatments to patients around the world."
About RiboX Therapeutics
RiboX Therapeutics is a global biotech company focused on discovering and developing fully engineered circular RNA therapeutics. Co-founded in 2021 by Drs. Ling-Ling Chen, Dan Peer, and Weiyi Zhang, RiboX operates in Princeton, NJ, USA, Rehovot, Israel, and Shanghai, China. The company's pipeline spans various therapeutic areas, including radiation-induced xerostomia, monogenic diseases, autoimmune diseases, and vaccines.
