Sodium phenylbutyrate is a salt of an aromatic fatty acid. The compound is used to treat urea cycle disorders, because its metabolites offer an alternative pathway to the urea cycle to allow excretion of excess nitrogen. Sodium phenylbutyrate is also a histone deacetylase inhibitor and chemical chaperone, leading respectively to research into its use as an anti-cancer agent and in protein misfolding diseases such as cystic fibrosis. It is used as adjunctive therapy for the management of chronic urea cycle disorders due to deficiencies in carbamylphosphate (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase. It is indicated in all neonatal- onset efficiency presenting within the first 28 days of life. Also indicated in patients with late-onset, presenting after the first month of life with a history of hyperammonemic encephalopathy. 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. The kidneys then excrete Phenylacetylglutamine. PBA (phenylbutyric acid) is absorbed from the intestine and converted by way of β-oxidation to the active moiety, phenylacetic acid (PAA). PAA is conjugated with glutamine in the liver and kidney by way of N-acyl coenzyme A-l-glutamine N-acyltransferase to form phenylacetylglutamine (PAGN). Like urea, PAGN incorporates two waste nitrogens and is excreted in the urine. 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.

Phenylacetic acid (abr. PAA and synonyms are: α-toluic acid, benzeneacetic acid, alpha tolylic acid, 2-phenylacetic acid, β-phenylacetic acid) is an organic compound containing a phenyl functional group and acarboxylic acid functional group. Because it is used in the illicit production of phenylacetone (used in the manufacture of substituted amphetamines), it is subject to controls in countries including the United States and China Phenylacetic acid is used in some perfumes, possessing a honey-like odor in low concentrations, and is also used in penicillin G production. It is also employed to treat type II hyperammonemia to help reduce the amounts of ammonia in a patient's bloodstream by forming phenylacetyl-CoA, which then reacts with nitrogen-rich glutamine to form phenylacetylglutamine. This compound is then secreted by the patient's body. In Phase 2 of clinical research it investigated in the treatment of Brain and Central Nervous System Tumors.

Tauroursodeoxycholic acid (TUDCA) is an endogenous hydrophilic bile acid used clinically to treat certain liver diseases. It is approved in Italy and Turkey for the treatment of cholesterol gallstones and is an investigational drug in China, Unites States, and Italy. Tauroursodeoxycholic acid is being investigated for use in several conditions such as Primary Biliary Cirrhosis (PBC), insulin resistance, amyloidosis, Cystic Fibrosis, Cholestasis, and Amyotrophic Lateral Sclerosis. Tauroursodeoxycholate (TUDC) promote choleresis by triggering the insertion of transport proteins for bile acids into the canalicular and basolateral membranes of hepatocytes. In addition, Tauroursodeoxycholate exerts hepatoprotective and anti-apoptotic effects, can counteract the action of toxic bile acids and reduce endoplasmic reticulum stress. Tauroursodeoxycholate can also initiate the differentiation of multipotent mesenchymal stem cells (MSC) including hepatic stellate cells and promote their development into hepatocyte-like cells. Although the hepatoprotective and choleretic action of TUDC is empirically used in clinical medicine since decades, the underlying molecular mechanisms remained largely unclear.

Sodium phenylbutyrate is a salt of an aromatic fatty acid. The compound is used to treat urea cycle disorders, because its metabolites offer an alternative pathway to the urea cycle to allow excretion of excess nitrogen. Sodium phenylbutyrate is also a histone deacetylase inhibitor and chemical chaperone, leading respectively to research into its use as an anti-cancer agent and in protein misfolding diseases such as cystic fibrosis. It is used as adjunctive therapy for the management of chronic urea cycle disorders due to deficiencies in carbamylphosphate (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase. It is indicated in all neonatal- onset efficiency presenting within the first 28 days of life. Also indicated in patients with late-onset, presenting after the first month of life with a history of hyperammonemic encephalopathy. 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. The kidneys then excrete Phenylacetylglutamine. PBA (phenylbutyric acid) is absorbed from the intestine and converted by way of β-oxidation to the active moiety, phenylacetic acid (PAA). PAA is conjugated with glutamine in the liver and kidney by way of N-acyl coenzyme A-l-glutamine N-acyltransferase to form phenylacetylglutamine (PAGN). Like urea, PAGN incorporates two waste nitrogens and is excreted in the urine. 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.

Sodium phenylbutyrate is a salt of an aromatic fatty acid. The compound is used to treat urea cycle disorders, because its metabolites offer an alternative pathway to the urea cycle to allow excretion of excess nitrogen. Sodium phenylbutyrate is also a histone deacetylase inhibitor and chemical chaperone, leading respectively to research into its use as an anti-cancer agent and in protein misfolding diseases such as cystic fibrosis. It is used as adjunctive therapy for the management of chronic urea cycle disorders due to deficiencies in carbamylphosphate (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase. It is indicated in all neonatal- onset efficiency presenting within the first 28 days of life. Also indicated in patients with late-onset, presenting after the first month of life with a history of hyperammonemic encephalopathy. 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. The kidneys then excrete Phenylacetylglutamine. PBA (phenylbutyric acid) is absorbed from the intestine and converted by way of β-oxidation to the active moiety, phenylacetic acid (PAA). PAA is conjugated with glutamine in the liver and kidney by way of N-acyl coenzyme A-l-glutamine N-acyltransferase to form phenylacetylglutamine (PAGN). Like urea, PAGN incorporates two waste nitrogens and is excreted in the urine. 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.

Antineoplaston (Phenylacetylglutamine) is the amino acid acetylation product of phenylacetate (or phenylbutyrate after beta-oxidation). The chemical structure of Antineoplaston AS2-5 corresponds to phenylacetylglutamine. Two synthetic derivatives of Antineoplaston A10 were named Antineoplaston AS2-1 and AS2-5. All antineoplaston formulations were submitted for Phase I clinical studies in advanced cancer patients. The treatment was free from significant side-effects and resulted in objective response in a number of advanced cancer cases. Antineoplastons are an experimental cancer therapy developed by S.R. Burzynski, MD, PhD. Chemically, antineoplastons are a mixture of amino acid derivatives, peptides, and amino acids found in human blood and urine. The developer originally isolated antineoplastons from human blood and later found the same peptides in urine. Urine was subsequently used because it was less expensive and easier to obtain. Since 1980, antineoplastons have been synthesized from commercially available chemicals at the Burzynski Research Institute. According to the developer, antineoplastons are part of a biochemical surveillance system in the body and work as "molecular switches." For the developer, cell differentiation is the key to cancer therapy. At the molecular level, abnormal cells that are potential cancer cells need to be "switched" to normal mode. Antineoplastons are the surveillance system that directs cancer cells into normal channels of differentiation. According to statements published by the developer, people with cancer lack this surveillance system because they do not have an adequate supply of antineoplastons.