Regulus hits further setbacks as clinical hold upheld
- Shares fell by 20% after hours as Regulus announced on Friday that the Food and Drug Administration has maintained the clinical hold on its lead development program and requested more data.
- Halfway through 2016, the FDA put a clinical hold on Regulus Therapeutics' RG-101 injectable hepatitis C drug development program, after a second case of jaundice was reported. Regulus submitted a response, including details of a clinical mechanism for the jaundice.
- The FDA has asked for final safety and efficacy from the ongoing clinical trial, which will be available once 48 weeks of follow-up has been completed, and Regulus expects to submit this around the fourth quarter of 2017. The FDA also requires preclinical data and expert evaluation of liver safety data, along with an updated risk/benefit assessment.
RG-101 targets a microRNA in the liver that supports the replication and translation of the hepatitis C virus in the liver. It's advantages are that it's active against all genotypes of the virus, has a different mechanism of action to those already on the market, and could shorten the treatment time of other hepatitis C drugs when used in combination.
Back in 2014, RG-101 was seen as a potential HCV blockbuster. While Regulus tries to remain upbeat, these advantages will be somewhat moot if it can't get the drug through its clinical trials, which have been on hold since July 2016.
"While we are disappointed that the clinical hold was not lifted at this time, we plan to continue to work with the FDA to address their additional requests as we seek the removal of the clinical hold," said Timothy Wright, chief R&D officer of Regulus.
Regulus has other microRNA-targeting drugs in its pipeline, and its technology is supported by a number of big pharma companies. RG-012, in collaboration with Sanofi Genzyme, is in Phase 2 for the treatment of the orphan disease Alport syndrome, and RG-125 (AZD4076) is in Phase 2 for non-alcoholic steatohepatitis (NASH) in collaboration with AstraZeneca.
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