Additional Relevant Details In the written communication, the FDA requested the following from the company: detailed safety data analysis from preclinical and clinical studies; exploration of potential mechanisms of hepatoxicity in non-clinical models; review and input from independent hepatotoxicity experts; additional PK data from the US Phase 1 study; and a risk/benefit assessment for the proposed therapeutic regimens containing RG-101. The company anticipates submitting the necessary information by early Q4 2016. TheFDA will notify Regulus of its decision within 30 days of receipt of the complete response to the issues.