In the event you guessed producers, you possibly can be fallacious. A minimum of this is in line with a brand new learn about by way of Mattingly et al. (2023) in JAMA Well being Discussion board. The usage of a pattern of the 45 generic medicine with >$100m in Phase D and utilized by >1m beneficiaries, the authors discovered that:
…Medicare Phase D spent $11.8 billion for 690 million claims (imply, $22.50 in step with declare; 95% CI, $18.28-$26.72 in step with declare), representing 5.5% of all Phase D spending ($216 billion) in 2021. The $22.50 was once allotted as follows: $9.18 (40.8%) represents PBM gross benefit; $3.87 (17.2%), pharmacy gross benefit; $2.71 (12.0%), wholesaler gross benefit; and $6.73 (29.9%), producer earnings. General middleman gross benefit (PBM, wholesaler, and pharmacy) ranged from −12.3% to 88.6% of Medicare Phase D spending.

The entire paper is right here.