Regulus Therapeutics said it intends to discontinue clinical development of RG-101, a microRNA treatment for hepatitis C.
The company plans to discontinue the HCV candidate development, after the completion of the one remaining clinical study that is expected in July this year.
Regulus has decided to terminate the trial due to the identification of high levels of bilirubin in the blood, which was confirmed from the pre-clinical investigation and assessment of the clinical data from RG-101.
According to the company, the combination of factors such as inhibition of conjugated bilirubin transport by RG-101, impaired baseline bilirubin transport in HCV patients and the preferential uptake of RG-101 by hepatocytes contributed to the hyperbilirubinemia.
Based on the date from the RG-101 program, the company has identified alternative compounds to target miR-122, which maintain potent HCV antiviral activity while lacking inhibition of the bilirubin transporter.
Separately, AstraZeneca has unveiled plans to terminate the clinical development program for AZD4076 (RG-125) to treat non-alcoholic steatohepatitis (NASH) in Type 2 Diabetes/Pre-diabetes.
As per the terms of the deal, AstraZeneca will return he rights of AZD4076 to Regulus, when the termination becomes effective in one year.
In April 2015, AZD4076 (RG-125) was jointly identified and selected as a clinical candidate under the strategic collaboration to discover, develop and commercialize microRNA therapeutics.
The company has also announced plans to initiate phase II clinical programs for RG-012 for the treatment of Alport syndrome.
Regulus president and CEO Jay Hagan said: "We are squarely focused on taking the steps necessary to advance our pipeline and continue building shareholder value.
“To that end, we recognize that we must be disciplined in our investment choices and focus our resources and capital on our most promising discovery and development programs, including the application of important development, regulatory and commercial considerations.”
Image: Regulus to discontinue the clinical development of RG-101. Photo: courtesy of jk1991 / FreeDigitalPhotos.net.