Both companies told The Hill their arrangements are lawful and well-intended. A spokesperson from Merck said the company "negotiate[d] contracts that help meet [customers'] needs."
"Those negotiations are private and all individual contracts are confidential. The terms of the contracts are lawful, and we strongly disagree with any statement or implication suggesting otherwise," a spokesperson said in an email.
Sanofi Pasteur said their contracts are crafted for healthcare providers "who wish to offer their members discounts on our vaccines."
"Sanofi Pasteur’s primary goal is, and has always been, to offer our healthcare provider customers innovative, safe and effective vaccines at competitive prices to maximize immunization rates and protect public health," the company said in statement.
The groups that wrote to the FTC said the bundling discounts are offered under an exclusivity agreement that requires a healthcare buyer to use a single supplier for vaccines. The discounts are revoked, the groups allege, if any member of the practice purchases vaccines from another company.
They said the exclusivity agreements could hurt patients since other companies might provide better vaccines for certain illnesses than the two major drug suppliers.
“Parents assume doctors are making drug decisions based on the patient, but in fact, they are making decisions based on the price,” Sloan said.
“That will be cold comfort to a young woman who discovers she might have avoided cervical cancer if only she’d received the right vaccine as a girl.”
States are already struggling to pay for healthcare and children's vaccines without additional costs and complications, NLARx executive director Sharon Treat added.
"This bundling practice increases costs and may reduce access to appropriate healthcare," Treat said in a statement. "It is appropriate for the FTC to take a look at the practices and determine if it meets antitrust and consumer standards.
— This story was updated with comment from Merk and Sanofi Pasteur at 3:49 p.m.