Regulus Therapeutics Inc. (RGLS) SEC Filing 10-Q Quarterly report for the period ending Wednesday, September 30, 2020

RGLS4326 for Autosomal Dominant Polycystic Kidney Disease: In July, 2020 the Company completed dosing in the MAD clinical study for RGLS4326 in healthy volunteers. The Phase 1 MAD study is a randomized, double blind, placebo-controlled clinical trial evaluating three different dose levels of RGLS4326 for safety, tolerability and pharmacokinetic properties. Top-line results showed that RGLS4326 is well-tolerated with no serious adverse events reported. Preliminary results suggest plasma exposure is dose proportional. In July, 2020 the FDA granted Orphan Drug Designation to RGLS4326 for ADPKD. The Company plans to initiate a Phase 1b open-label, short-term multiple dose study in patients with ADPKD in the second half of 2020. The study will evaluate RGLS4326 for safety, pharmacokinetics, and changes in levels of polycystin 1 (PC1) and polycystin 2 (PC2). Patients with ADPKD, due to the mutation in the PKD gene, have been reported to have low levels of PC1 and PC2. This study is designed to evaluate whether different dose levels of RGLS4326 can increase levels of PC1 and PC2 in ADPKD patients.

Advancement of Hepatitis B virus (HBV) Program: The Company has identified several microRNA targets that serve as host factors for the hepatitis B virus (HBV). Our lead compound directed to one of the host microRNAs has demonstrated nanomolar potency against HBV DNA replication and more than 95% reduction in Hepatitis B surface antigen in in vitro studies. Additionally, we have demonstrated reduction of HBV DNA, surface antigen and pgRNA in an in vivo efficacy model. We believe that targeting a host factor in the liver represents a unique mechanism of action for treatment of the virus compared to other programs in development and holds the potential for achieving a functional cure. We have nominated a development candidate and plan to commence IND-enabling activities.