SODIUM PHENYLBUTYRATE powder

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

SODIUM PHENYLBUTYRATE (UNII: NT6K61736T) (PHENYLBUTYRIC ACID - UNII:7WY7YBI87E)

Available from:

Par Pharmaceutical, Inc.

INN (International Name):

SODIUM PHENYLBUTYRATE

Composition:

SODIUM PHENYLBUTYRATE 0.94 g in 1 g

Administration route:

ORAL

Prescription type:

PRESCRIPTION DRUG

Therapeutic indications:

Sodium phenylbutyrate powder 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. Sodium phenylbutyrate powder must be combined with dietary protein restriction and, in some cases, essential amino acid supplementation. (See Nutritional Supplementation subsection of the DOSAGE AND ADMINISTRATION section.) Previously, neona

Product summary:

Sodium phenylbutyrate powder is available in 500 cc bottles, which hold 266 grams of powder, containing            250 grams of sodium phenylbutyrate (NDC 49884-006-04). The bottles are equipped with child-resistant caps. Measurers are provided. A teaspoon and tablespoon come with each bottle. A yellow color teaspoon and blue color tablespoon are enclosed with this product. Each level yellow teaspoon (enclosed) dispenses 3.2 grams of powder and 3 grams of sodium phenylbutyrate. Each level blue tablespoon (enclosed) dispenses 9.1 grams of powder and 8.6 grams of sodium phenylbutyrate.  Store at 20º to 25ºC (68° to 77°F); [See USP Controlled Room Temperature]; Excursions permitted to 15° to 30°C (59° to 86°F).   After Opening, Keep Bottle Tightly Closed.

Authorization status:

Abbreviated New Drug Application

Summary of Product characteristics

SODIUM PHENYLBUTYRATE- SODIUM PHENYLBUTYRATE POWDER
PAR PHARMACEUTICAL, INC.
----------
SODIUM PHENYLBUTYRATE POWDER
RX ONLY
DESCRIPTION
Sodium phenylbutyrate powder nasogastric, or gastrostomy tube
administration contain sodium
phenylbutyrate. Sodium phenylbutyrate powder is an off-white
crystalline substance which is soluble in
water and has a strong salty taste. Sodium phenylbutyrate also is
freely soluble in methanol and
practically insoluble in acetone and diethyl ether. It is known
chemically as 4-phenylbutyric acid,
sodium salt with a molecular weight of 186 and the molecular formula C
H O Na.
Chemical Structure:
Each gram of sodium phenylbutyrate powder contains 0.94 grams of
sodium phenylbutyrate and the
inactive ingredients calcium stearate and colloidal silicon dioxide.
CLINICAL PHARMACOLOGY
Sodium phenylbutyrate is a pro-drug and is rapidly metabolized to
phenylacetate. Phenylacetate is a
metabolically-active compound that conjugates with glutamine via
acetylation to form
phenylacetylglutamine. Phenylacetylglutamine then is excreted by the
kidneys. On a molar basis, it is
comparable to urea (each containing two moles of nitrogen). Therefore,
phenylacetylglutamine
provides an alternate vehicle for waste nitrogen excretion.
PHARMACOKINETICS
GENERAL:
Pharmacokinetic studies have not been conducted in the primary patient
population (neonates, infants, and
children), but pharmacokinetic data were obtained from normal adult
subjects.
ABS ORPTION:
Peak plasma levels of phenylbutyrate occur within 1 hour after a
single dose of 5 grams of sodium
phenylbutyrate powder with a C
of 195 mcg/mL under fasting conditions. The effect of food on
phenylbutyrate's absorption is unknown.
DIS POS ITION:
The overall disposition of sodium phenylbutyrate and its metabolites
has not been characterized fully.
However, the drug is known to be metabolized to phenylacetate and
subsequently to
phenylacetylglutamine.
Following oral administration of 5 grams of the powder, measurable
plasma levels of phenylbutyrate
and phenylacetate