Lawyers touting a $500 million settlement over insulin pricing are back at the drawing board after a judge refused to certify their class.

Insulin prices have drawn the interest of federal and state regulators, many of which, including California, have sued manufacturers Eli Lilly and Co., Novo Nordisk Inc. and Sanofi-Aventis U.S. LLC and, in some cases, numerous pharmacy benefit managers.

Judge Brian R. Martinotti of the District of New Jersey. (Courtesy Photo) U.S. District Judge Brian Martinotti of the District of New Jersey. Courtesy photo