Shares of Regulus Therapeutics Inc. were set to sell off in after-hours trade Monday, after the biopharmaceutical company said the Food and Drug Administration placed its investigational new drug for the treatment of chronic hepatitis C virus infection on clinical hold. The stock was halted for news, and is scheduled to being trading again at 4:40 p.m. ET. Regulus said the FDA initiated the clinical hold after a second serious adverse event of jaundice was reported. Regulus said it expects to receive a formal letter from the FDA within 30 day, and plans to work with the FDA as it seeks a release of the clinical hold. The stock had plunged 43% year to date through Monday, while the SPDR S&P Biotech ETF has lost 29% and the S&P 500 has slipped 2.1%.Read more..