The biggest enticement that large pharmacy benefit managers offer to the employers that hire them is drug rebates — a steady stream of money sent back to their clients, a tangible symbol of the discounts that PBMs are able to wrangle out of pharmaceutical companies.
PBMs, the middlemen of drug pricing negotiations, also claim portions of those lucrative rebates for themselves. So when new market developments threaten to diminish or wipe away that revenue stream, PBMs find crafty ways to keep as much of those dollars as possible — often at the expense of employers.
One such case occurred last year, when a wave of Humira biosimilars entered the market and drug companies slashed the list prices of their insulin products. CVS Caremark, the PBM owned by CVS Health that oversees the prescription drug benefits of 103 million people, told its employer clients that it anticipated “more lower-cost products (including specialty biosimilars) may become preferred products” on its lists of approved drugs for 2024, according to documents obtained by STAT.