US Probing Drug Middlemen’s New Units That Negotiate Price Cuts

US authorities are looking into new groups that were formed to negotiate drug discounts but may actually be further obscuring how much the medicines cost.

Officials are working to pierce multiplying, opaque layers between the companies that make medicines and the people who take them. Cigna Group, CVS Health Corp. and UnitedHealth Group Inc. have long controlled the largest pharmacy benefit managers, or PBMs, that traditionally negotiated rebates with drugmakers. In recent years, those companies have each launched new entities called group purchasing organizations, or GPOs, to take over that job.

Most people have never heard of these GPOs. ...