Amlexanox (trade name Aphthasol) is an

anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs remedy pain by reducing inflammation as o ...

antiallergic An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies. In technical terms ...

immunomodulator Immunotherapy or biological therapy is the treatment of disease by activating or suppressing the immune system. Immunotherapies designed to elicit or amplify an immune response are classified as ''activation immunotherapies,'' while immunotherap ...

used to treat recurrent

aphthous ulcer Aphthous stomatitis, or recurrent aphthous stomatitis (RAS), is a common condition characterized by the repeated formation of benign and non-contagious mouth ulcers (aphthae) in otherwise healthy individuals. The informal term ''canker sore'' i ...

s (canker sores), and (in Japan) several inflammatory conditions. This drug has been discontinued in the U.S.

Medical uses

Amlexanox is the active ingredient in a common topical treatment for recurrent

aphthous ulcers Aphthous stomatitis, or recurrent aphthous stomatitis (RAS), is a common condition characterized by the repeated formation of benign and non- contagious mouth ulcers (aphthae) in otherwise healthy individuals. The informal term ''canker sore'' ...

of the mouth (canker sores), reducing both healing time and pain. Amlexanox 5% paste is well tolerated, and is typically applied four times per day directly on the ulcers. A 2011 review found it to be the most effective treatment of the eight treatments investigated for recurrent canker sores. It is also used to treat ulcers associated with Behçet disease. In Japan, it is used to treat bronchial asthma, allergic

rhinitis Rhinitis, also known as coryza, is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip. The inflammation is caused by viruses, bacteria, irrita ...

and

conjunctivitis Conjunctivitis, also known as pink eye, is inflammation of the outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The ...

Contraindications

The drug is contraindicated in those with known allergies to it.

Adverse effects

Amlexanox may cause a slightly painful stinging or burning sensation, nausea or diarrhea.

Mechanism of action

Its mechanism of action is not well-determined, but it might inhibit inflammation by inhibiting the release of

histamine Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered ...

and

leukotrienes Leukotrienes are a family of eicosanoid inflammatory mediators produced in leukocytes by the oxidation of arachidonic acid (AA) and the essential fatty acid eicosapentaenoic acid (EPA) by the enzyme arachidonate 5-lipoxygenase. Leukotri ...

. It has been shown to selectively inhibit TBK1 and IKK-ε, producing reversible weight loss and improved insulin sensitivity, reduced inflammation and attenuated hepatic steatosis without affecting food intake in obese mice. It produced a statistically significant reduction in

glycated hemoglobin Glycated hemoglobin, also known as HbA1c, glycohemoglobin, hemoglobin A1c, A1C, is a form of hemoglobin (Hb) that is chemically linked to a sugar. Most monosaccharides, including glucose, galactose and fructose, spontaneously (i.e. non-enzymat ...

and fructosamine in obese patients with

type 2 diabetes Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urinatio ...

and

nonalcoholic fatty liver disease Non-alcoholic fatty liver disease (NAFLD), also known as metabolic (dysfunction) associated fatty liver disease (MAFLD), is excessive fat build-up in the liver without another clear cause such as alcohol use. There are two types; non-alcoholic ...

Chemistry

The chemical itself is an odorless, white to yellowish-white powder. The 5% preparation for patient use is an adherent beige paste, and it is also available in some countries as a tablet that adheres to the ulcer in the mouth.

Pharmacokinetics

Amlexanox applied to an aphthous ulcer is largely absorbed through the gastrointestinal tract; an insignificant amount enters the

bloodstream The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

through the ulcer itself. After a single 100 mg dose, mean maximum serum concentration occurs 2.4 +/- 0.9 hours after application, with a half-life of elimination (through urine) of 3.5 +/- 1.1 hours. With multiple daily applications (four doses per day), steady state serum levels occur after one week, with no accumulation occurring after four weeks.

History

The patent for its use as a treatment for aphthous ulcers was issued in November 1994 to inventors Kakubhai R. Vora, Atul Khandwala and Charles G. Smith, and assigned to Chemex Pharmaceuticals, Inc.

Society and culture

Economics

A 2011 review found a one-week supply of amlexanox 5% paste to cost $30.

Research

A review found that, , robust studies investigating its effectiveness alongside other canker sore treatments were still needed. Because it is an inhibitor of the

protein kinase A protein kinase is a kinase which selectively modifies other proteins by covalently adding phosphates to them (phosphorylation) as opposed to kinases which modify lipids, carbohydrates, or other molecules. Phosphorylation usually results in a fu ...

s TBK1 and IKK-ε, which are implicated in the etiology of

type II diabetes Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urinatio ...

and

obesity Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's ...

, amlexanox may be a candidate for human clinical trials testing in relation to these diseases.

Synthesis

References

{{Drugs for obstructive airway diseases Anti-inflammatory agents Leukotriene antagonists Carboxylic acids Isopropyl compounds