"[D]espite the continued consolidation and vertical integration of PBMs, health plans may minimize any adverse impact by contractually limiting the rights and responsibilities of PBM-affiliated organizations.... To protect against PBMs steering prescription drugs toward their affiliated pharmacies via formulary changes, health plans may maintain leverage over their formularies by exercising final approval rights over the content, form, format, and/or frequency of their formularies and formulary changes under their PBM contracts."  MORE >>