CLEVELAND—Lawyers for pharmacy chains including CVS and Walgreens on Monday argued they were not to blame for the opioid epidemic, as jurors prepared to consider whether to hold them responsible for the devastation the drug crisis caused in two Ohio counties. Mark Lanier, a lawyer for Lake and Trumbull counties, told a federal jury in Cleveland that a verdict in the case against CVS Health Corp, Walgreens Boots Alliance Inc., and Walmart Inc. would have ramifications across the country. The trial is the first the pharmacy chains have faced in thousands of lawsuits by states and local governments seeking to hold them liable for an epidemic that U.S. health officials say has led to nearly 500,000 opioid overdose deaths over two decades. “You get to decide what will be the most seminal case in pharmacy history,” Lanier said in his closing argument. He argued that companies created a public nuisance …