The Daily Item -- RIVERSIDE — Seven months after Merck bought back the plant it sold just a few years earlier, company officials Tuesday announced plans to sell off one product line and outsource others by the end of 2013 in an attempt to cut costs. “The important thing is we are focusing on our antibiotic franchise,” company spokeswoman Betse Humphrey said. “It’s good news. We’re looking at this as a way to remain in the community.”