LITTLE ROCK, Arkansas: Arkansas Attorney-General Leslie Rutledge has filed a lawsuit accusing drugmakers and pharmacy benefit managers of colluding to drive up insulin prices.

The move is the latest in a series of lawsuits aimed at countering skyrocketing costs of the critical diabetes medicine.

The lawsuit, filed in Pulaski County, Arkansas state court, is aimed at Eli Lilly and Co, Novo Nordisk A/S and Sanofi SA, which together sell the majority of insulin drugs in the U.S..

The lawsuit also names the nation's leading pharmacy benefit managers, UnitedHealth Group Inc's Optum unit, CVS Health Corp's CVS Caremark and Cigna Corp's Express Scripts.

In a statement, Eli Lilly said it was "disappointed" by "inaccurate claims" in the lawsuit, adding that it has voluntarily ensured that patients can purchase its insulin for $35 per month or less.

According to the American Diabetes Association, some 8.4 million of the 37 million people with diabetes use insulin drugs in the U.S.

According to a 2021 Congressional report, Eli Lilly raised the price of its insulin product, Humalog, by 1,219 percent per vial since it launched, while Novo Nordisk raised the price of NovoLog by 627 percent since its introduction, and Sanofi has increased the price of Lantus by 715 percent.

In the lawsuit, Rutledge said that the pharmacy benefit managers, are violating an Arkansas law against deceptive business practices by accepting higher prices in exchange for generous rebates from the drugmakers in order to enrich themselves, rather than negotiating lower prices on behalf of patients.

Similar lawsuits brought by the state of Minnesota, city of Miami and groups of drug purchasers are already pending.