Aetna’s new policy on PANS/PANDAS and Practical Takeaways for Clinicians and Families

The past few years, Neuroimmune Foundation has consistently engaged major insurance companies related to PANS/PANDAS coverage, including meetings with senior medical policy leaders at major U.S. health insurance companies who are directly involved in medical policy development and have participated in numerous policy amendments. These discussions focused on insurance coverage considerations for infusion-based therapies for PANS/PANDAS, including IVIG and rituximab. Additionally, across the past three years, more than twenty physicians from major health insurance companies have joined Neuroimmune Foundation’s CME free of charge to learn about PANS/PANDAS treatments. Many of them attend each year.

These discussions and the education we’ve been able to provide are highly relevant today as recent policy developments across the insurance landscape, including Aetna’s newly expanded Clinical Policy Bulletin related PANS/PANDAS, reflect many of the principles that were discussed at that time. These public updates provide a useful window into how insurers evaluate medical necessity, evidence, and clinical documentation when making coverage determinations.

What follows are key insights from discussions that may help families and clinicians navigate treatment approvals more effectively.

• Diagnostic terminology and coding – Insurers are well aware of the range of diagnostic terms used to describe PANS/PANDAS and related conditions, including autoimmune encephalitis and post-infectious autoimmune encephalopathy. While alternative coding may be clinically appropriate, insurers generally recognize when prior authorizations are associated with PANS/PANDAS and evaluate them accordingly.
• Appeals and letters of medical necessity – Even when a plan excludes PANS/PANDAS by name, infusion-based therapies may be approved on appeal when supported by a strong letter of medical necessity. Effective letters explicitly reference consensus guidelines, demonstrate how those guidelines were followed, and clearly explain why infusion therapy is medically appropriate for the individual patient.
• Scope and duration of treatment requests – Initial requests for a limited number of infusions (typically one to three) are viewed as more reasonable than extended treatment courses at the outset. Insurers are more likely to approve additional treatment if there is clear documentation of clinical improvement.
• Accuracy in diagnosis coding – Using an incorrect primary diagnosis code can result in automatic denials. Diagnosis codes should directly align with the treatment being requested and the clinical rationale provided.
• Use of evidence accepted in conventional care – Insurers evaluate requests based on evidence broadly accepted within conventional medical practice. Submissions that rely heavily on non-standard testing or unsupported diagnostic frameworks may weaken otherwise legitimate requests.
• Expectation of comprehensive evaluation – For severely affected patients, insurers often expect documentation of a thorough medical workup, which may include MRI, EEG, and lumbar puncture. Insurers frequently note that the absence of this documentation weakens requests for advanced therapies, regardless of symptom severity.
• Stepwise treatment documentation – Insurers expect to see evidence that standard interventions such as extended courses of antibiotics, NSAIDs, and corticosteroids have been attempted and documented prior to requesting IVIG or other infusion-based therapies. This stepwise approach aligns with existing consensus recommendations and is viewed as foundational to medical necessity.
• Diagnosis-specific supporting evidence – Clinical documentation should clearly support the diagnosis being claimed. For PANDAS, this includes evidence of streptococcal infection. For PANS, documentation of the suspected trigger is expected. Insurers may also look for evidence that potential streptococcal carriers within the household have been identified and treated. (This is a direct result of the physicians at these health insurance companies taking Neuroimmune Foundation’s CME).

Beyond individual approvals, in our discussion with insurers, they consistently pointed to factors that would influence broader policy evolution (ie. What our community can fund and do to more quickly continue to impact policy in this space):

• High-quality, peer-reviewed research – Expanded research strengthens the evidence base insurers rely on when revising policies. Continued investment in research and publication like our two Special Issues published in peer-reviewed journals, remains essential.
• Clear clinical education – Insurers rely on consistent, guideline-aligned clinical practices. Educating clinicians on both diagnostic standards and documentation expectations plays a meaningful role in improving access to care. Neuroimmune Foundation’s ECHO and 500 fee waivers to the 2026 Inflammatory Brain Disorders Conference provide this accredited Continuing Medical Education to clinicians free of charge.

Policy change in healthcare is rarely immediate. It is shaped over time through research, education, dialogue, and consistent clinical practice. Recent public policy updates, such as Aetna’s expanded clinical bulletin, highlight the importance of sustained, evidence-based engagement.

At Neuroimmune Foundation, we remain focused on advancing the research, consensus development, and clinician education necessary to reduce barriers to care and improve outcomes for individuals and families affected by PANS/PANDAS.

For reference, Aetna’s Clinical Policy Bulletin can be viewed here.