Regulus Therapeutics Inc. announced that it received written communication from the U.S. Food and Drug Administration (FDA) that the clinical development program for RG-101 remains on clinical hold. In June 2016, RG-101 was placed on clinical hold following the Company's submission of a second serious adverse event (SAE) of jaundice. Late last year, Regulus submitted a complete response to the FDA's initial request for information, which included identification of a potential mechanism of hyperbilirubinemia. The Company also submitted a proposal to mitigate this risk. Subsequently, the FDA has requested the final safety and efficacy data from on-going RG-101 clinical and pre-clinical studies before reconsidering the clinical hold. These data will be available once the current study protocols are complete through 48 weeks of follow up, which is anticipated in the fourth quarter. The FDA also requested additional expert review of liver safety data in light of the proposed mechanism of hyperbilirubinemia.