Background

Kebilidi (eladocagene exuparvovec-tneq) is a gene therapy for aromatic L-amino acid decarboxylase deficiency (AADC deficiency). It's the first gene therapy approved in the U.S. for direct delivery to the brain to treat this rare neurological disorder. AADC deficiency impairs the brain's ability to produce neurotransmitters like dopamine and serotonin. KEBILIDI uses a modified virus to deliver a healthy copy of the DDC gene to brain cells, enabling them to produce the necessary neurotransmitters.

Policy (Criteria)

Kebilidi is considered MEDICALLY NECESSARY when the following criteria is met:

1. Diagnosis of AADC deficiency as evidenced by documentation of positive testing from two of the following core diagnostic tests (see Appendix E):
   1. Cerebrospinal fluid (CSF) neurotransmitter metabolite panel;
   2. Single gene or genetic panel testing;
   3. Plasma enzyme assay;
2. Prescribed by or in consultation with a geneticist or neurologist;
3. Age ≥ 16 months;
4. Evidence of classic clinical symptoms of AADC deficiency (e.g., hypotonia, dystonia, oculogyric crisis, unable to stand, developmental retardation)
5. Documentation that member has achieved skull maturity by neuroimaging;
6. Documentation of baseline laboratory tests demonstrating anti-AAV2 neutralizing antibody titer < 1,200 fold or ELISA optical density (OD) > 1;
7. Dose does not exceed 1.8 × 1011 vg (0.32 mL total volume).

 Approval duration: one-time dose per lifetime

References

1. Kebilidi prescribing information. PTC Therapeutics, Inc. Warren, NJ. November 2024
2. AADC Insights. Accurate identification can help improve the care and management of patients with AADC deficiency1. Accessed August 2025.
3. Subject: Eladocagene exuparvovec-tneq (Kebilidi) Suspension for Intraputaminal Infusion. (2025). BCBSFL. https://mcgs.bcbsfl.com/MCG?mcgId=09-J5000-06&pv=false

Coding Section

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each Policy. They may not be all-inclusive.

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, technology assessment program (TEC) and other non-affiliated technology evaluation centers, reference to federal regulations, other plan medical policies, and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

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