But some of the strongest consumer and patient protections have been championed by conservative or moderate states. Texas and Nevada bar insurers from changing their prescription drug formulary more than once per year. Montana requires insurers that participate on the Affordable Care Act marketplace to offer at least one mid-level plan that only charges members co-pays for drugs.

The study also recommends that state commissioners take a hard look at pharmacy and therapeutics committees, the panel of medical professionals and other stakeholders that most insurers rely on to craft their drug formularies.

Despite federal regulations governing such committees, there are major transparency issues and conflicts of interest, the report said. States should require that such committees meet at least quarterly and keep written documentation of their reasoning for any drug plan changes, the study declared.

Pharmacy and therapeutics committee members should also have to disclose their economic interests in any drug companies that could benefit from the committee’s decision, the report said.

“States are moving ahead,” Katie Keith, an attorney who works with NAIC and helped write the report, told Kaiser Health News. “There are best practices out there and states are making changes.”