"Public Citizen urges you to appoint an independent entity — such as your department's Office of Inspector General — to conduct a thorough investigation."
In its letter, the group criticized the Centers for Medicare and Medicaid Services (CMS) for not using its authority to discourage wide-scale drug compounding conducted outside of parameters set by the Food and Drug Administration (FDA).
Public Citizen also slammed CMS guidance on compounded drugs as "ambiguous and conflicting."
Drug compounders customize medications for patients with special needs. Most operate on a small scale, but some firms have taken advantage of regulatory ambiguity to mass produce drugs that do not meet FDA safety standards.
So far, lawmakers have focused on the FDA's role in overseeing compounders and whether the agency could have used its current powers to prevent the outbreak. Discussion of Medicare policy as it relates to compounding has been limited.
In its letter to Sebelius, Public Citizen said that federal officials should be taken to task for the meningitis scare.
"This investigation must identify all CMS officials whose actions and decisions contributed to the agency's failure to prevent this public health catastrophe," the group wrote. "Ultimately, the senior leadership within the agency must be held accountable."
Public Citizen distributed the letter to a wide range of congressional leaders now probing the outbreak.
The compounder behind the deaths, the New England Compounding Center, is the firm behind the deaths. It shuttered this fall and faces several federal investigations.