Bipartisan legislation aimed at reforming pharmacy benefit manager practices might be high on lawmakers' list of priorities, but a new report from the Brookings Institution suggests "achieving large reductions in prescription drug costs will require approaches that look beyond PBMs."

Titled "A brief look at current debates about pharmacy benefit managers," the analysis provides an overview of the business of PBMs — focusing on drug rebates, pharmacy "spread" pricing, and PBMs' profits and "vertical" relationships.

The main takeaway? "[W]hile there are problems in the market for PBM services, they likely have modest effects on the overall affordability of prescription drugs," write Brookings fellows Matthew Fiedler, Loren Adler, and Richard G. Frank.