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CO-55 - Denial Journal
CARC CO — Contractual Obligation

CO-55

Procedure/treatment/drug deemed experimental/investigational by the payer

What This Code Means

The payer classifies this treatment as experimental or investigational and therefore not covered.

Common Causes

  • Newer treatment/drug not yet added to payer's covered services list
  • Off-label use of an approved drug

How to Resolve or Appeal

  1. Review the payer's medical policy on the specific treatment
  2. Submit clinical literature/documentation supporting standard-of-care use if applicable
  3. Discuss patient financial responsibility in advance for known experimental treatments

Educational reference only — not medical or legal advice. Always confirm code usage and appeal rights with the specific payer.

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