Here are some of the findings:

At the national level in 2021, the four largest PBMs (Express Scripts, OptumRx, CVS Health, and Prime Therapeutics) collectively had a 68% share of the PBM market for rebate negotiation. Express Scripts alone had a 21% share. Because health insurers tend to use the same PBMs to supply all three services, the shares and rankings for retail network management and claims adjudication were almost identical to rebate negotiation, according to the report.
The collective share of the four largest PBMs in the national commercial PBM market increased from 64% in 2020 to 68% in 2021. This was largely due to CVS Health acquiring Aetna, which owned its own PBM (Aetna Pharmacy Management) prior to the merger.
On average, local PBM markets were highly concentrated in 2020 and became even more concentrated in 2021, which also was due to the CVS Health-Aetna merger. Across product and geographic markets, average concentration and the fractions of markets that were highly concentrated increased. At least 80% of state- and metropolitan-area-level PBM markets were highly concentrated in 2021, the report notes.

Health insurers that were vertically integrated with a PBM covered 70% of all people with commercial drug insurance in 2021, up just one percentage point from 2020. Although the average vertical integration shares across states and metropolitan areas were somewhat lower (63% and 65%, respectively), there was wide variation across states and metropolitan areas. Some states had almost no vertical integration between insurers and PBMs, while others were almost entirely vertically integrated. South Dakota had the smallest vertical integration share (6%) and Utah had the highest vertical integration share (97%). Since a significant portion of the market was not vertically integrated, the risk of consumer harm from vertical mergers remains, AMA officials say.

Instant Insights /

Competition declines among PBM middlemen, analysis finds