The PBM market is dominated by three major players, who together handled about 76 percent of all prescription claims in 2018, according to Drug Channels Institute.
A breakdown of PBM market share, by total equivalent prescription claims managed in 2018:
1. Caremark (CVS Health) / Aetna: 30 percent
2. Express Scripts: 23 percent
3. OptumRx (UnitedHealth): 23 percent
4. Humana Pharmacy Solutions: 7 percent
5. MedImpact Healthcare Systems: 6 percent
6. Prime Therapeutics: 6 percent
7. All other PBMs + cash pay: 4 percent
Read the full report here.