Regulus Therapeutics Inc. (NASDAQ: RGLS) saw its shares cut in half early Tuesday morning following news of a clinical hold from the U.S. Food and Drug Administration (FDA). The company announced it received verbal notice from the FDA that its Investigational New Drug (IND) RG-101 for the treatment of chronic hepatitis C virus (HCV) infection has been placed on clinical hold.
Ultimately, the company expects it will receive a formal clinical hold letter from the FDA within 30 days and plans to work diligently with the agency to seek the release of the clinical hold.
The agency initiated the clinical hold after Regulus reported a second serious adverse event (SAE) of jaundice. The SAE occurred in a HCV patient with end-stage renal disease on dialysis enrolled in its on-going Phase 1 U.S. study 117 days after receiving a single dose of RG-101.
Timelines for Regulus’ three on-going studies of RG-101 are not expected to be impacted as all patients have been enrolled and completed their dosing of RG-101 and will continue with protocol scheduled visits. Regulus remains on track to deliver follow-up results from these studies at upcoming relevant scientific meetings.
For some background, Regulus is a biopharmaceutical company focused on the discovery and development of innovative medicines targeting microRNAs. Regulus has leveraged its oligonucleotide drug discovery and development expertise to develop a well-balanced microRNA therapeutics pipeline complemented by a maturing microMarkers biomarkers platform and a rich intellectual property estate to retain its leadership in the microRNA field.
Shares of Regulus closed Monday down 5.3% at $5.01, with a consensus analyst price target of $23.50 and a 52-week trading range of $4.82 to $11.59. Following the announcement, the stock was trading down nearly 50% at $2.68.