Subject: phenylbutyrate-Buphenyl 2121-A SGM P2022
|
BUPHENYL
(sodium phenylbutyrate)
|
|
sodium phenylbutyrate
|
Policy:
I. INDICATIONS
The indications below including FDA-approved
indications and compendial uses are considered a
covered benefit provided that all the approval criteria
are met and the member has no exclusions to the
prescribed therapy.
A. FDA-Approved Indication
Buphenyl is indicated as adjunctive therapy in the
chronic management of patients with urea cycle
disorders involving deficiencies of
carbamylphosphate synthetase (CPS), ornithine
transcarbamylase (OTC), or argininosuccinic acid
synthetase (AS). It is indicated in all patients with
neonatal-onset deficiency (complete enzymatic
deficiency, presenting within the first 28 days of
life). It is also indicated in patients with late-onset
disease (partial enzymatic deficiency, presenting
after the first month of life) who have a history of
hyperammonemic encephalopathy. It is important
that the diagnosis be made early and treatment
initiated immediately to improve survival. Any
episode of acute hyperammonemia should be
treated as a life-threatening emergency.
B. Compendial Use
Arginase deficiency
All other indications are considered
experimental/investigational and not medically necessary.
II. DOCUMENTATION
Submission of the following information is necessary
to initiate the prior authorization review:
A. Initial requests:
1. Enzyme assay, biochemical, or genetic testing results
supporting diagnosis; and
2. Lab results documenting baseline plasma ammonia
levels.
B. Continuation of therapy requests: lab results documenting a
reduction in plasma ammonia levels from baseline.
III. CRITERIA FOR INITIAL APPROVAL
Authorization of 12 months may be granted for chronic
management of urea cycle disorder (UCD) including arginase
deficiency, when both of the following criteria are met:
1. The diagnosis is confirmed by enzymatic, biochemical, or
genetic testing.
2. The member has elevated plasma ammonia levels at
baseline.
IV. CONTINUATION OF THERAPY
Authorization of 12 months may be granted for continued
treatment in members requesting reauthorization for chronic
management of a urea cycle disorder (UCD) including arginase
deficiency, who are experiencing benefit from therapy as
evidenced by a reduction in plasma ammonia levels from
baseline.
Place of Service:
Outpatient
The above policy is based on the following references:
- Buphenyl [package insert]. Lake Forest, IL: Horizon Pharma USA, Inc.; March 2021.
- Mew NA, Lanpher BC. Urea Cycle Disorders Overview. In: Pagon RA, Adam MP, Ardinger HH, et. al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2017 [updated June 22, 2017]. Available at: https://www.ncbi.nlm.nih.gov/books/NBK1217/?report=printable.
- Häberle J, Boddaert N, Burlina A, et al. Suggested guidelines for the diagnosis and management of urea cycle disorders. J Inherit Metab Dis. 2019;42(6):1192-1230.
- Wong D, Cederbaum S, Crombez, E. Arginase Deficiency. GeneReviews. August 2014; http://www.ncbi.nlm.nih.gov/books/NBK1159/.
Copyright Aetna Inc. All rights reserved. Pharmacy Clinical Policy Bulletins are developed by Aetna to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. This Clinical Policy Bulletin contains only a partial, general description of plan or program benefits and does not constitute a contract. Aetna does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Aetna or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. This Clinical Policy Bulletin may be updated and therefore is subject to change.
June 26, 2022
