While lawyers say a full announcement is expected soon, the three biggest U.S. drug distribution companies and the drugmaker Johnson & Johnson are on the verge of a $26 billion settlement covering thousands of government lawsuits over the toll of opioids across the U.S.including Tennessee, says a group of lawyers for local governments.The national settlement is expected to be the biggest single settlement in the complicated universe of litigation over the opioid epidemic in the U.S. It won’t end the cases, but it would change them.