Tranilast (

INN Inns are generally establishments or buildings where travelers can seek lodging, and usually, food and drink. Inns are typically located in the country or along a highway; before the advent of motorized transportation they also provided accommo ...

, brand name Rizaben) is an antiallergic drug. It was developed by

Kissei Kissei Pharmaceutical is a pharmaceutical company based in Matsumoto, Nagano, Japan. Products discovered or developed by Kissei include: * Difelikefalin * Fostamatinib (trade name Tavalisse) * Linzagolix * Mitiglinide (Glufast) * Remogliflozin etab ...

Pharmaceuticals and was approved in 1982 for use in Japan and South Korea for

bronchial asthma Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, coug ...

. Indications for

keloid Keloid, also known as keloid disorder and keloidal scar, is the formation of a type of scar which, depending on its maturity, is composed mainly of either type III (early) or type I (late) collagen. It is a result of an overgrowth of granulation t ...

and

hypertrophic scar A hypertrophic scar is a cutaneous condition characterized by deposits of excessive amounts of collagen which gives rise to a raised scar, but not to the degree observed with keloids. Like keloids, they form most often at the sites of pimples, body ...

were added in the 1980s.

Medical uses

It is used in Japan, South Korea, and China to treat asthma,

keloid scars Keloid, also known as keloid disorder and keloidal scar, is the formation of a type of scar which, depending on its maturity, is composed mainly of either type III (early) or type I (late) collagen. It is a result of an overgrowth of granulation t ...

, and

s, and as an ophthalmic solution for allergic pink eye. It should not be taken by women who are or might become pregnant, and it is secreted in breast milk.

Interactions

People who are taking

warfarin Warfarin, sold under the brand name Coumadin among others, is a medication that is used as an anticoagulant (blood thinner). It is commonly used to prevent blood clots such as deep vein thrombosis and pulmonary embolism, and to prevent strok ...

should not also take tranilast, as they interact. It appears to inhibit

UGT1A1 UDP-glucuronosyltransferase 1-1 also known as UGT-1A is an enzyme that in humans is encoded by the ''UGT1A1'' gene. UGT-1A is a uridine diphosphate glucuronosyltransferase (UDP-glucuronosyltransferase, UDPGT), an enzyme of the glucuronidation path ...

so will interfere with metabolism of drugs that are affected by that enzyme.

Adverse effects

When given systemically, tranilast appears to cause liver damage; in a large well-conducted clinical trial it caused

elevated transaminases In medicine, the presence of elevated transaminases, commonly the transaminases alanine transaminase (ALT) and aspartate transaminase (AST), may be an indicator of liver dysfunction. Other terms include transaminasemia, transaminitis, and elevated ...

three times the upper limit of normal in 11 percent of patients, as well as anemia,

kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...

failure, rash, and problems urinating. Given systemically it inhibits blood formation, causing

leukopenia Leukopenia () is a decrease in the number of leukocytes (WBC). Found in the blood, they are the white blood cells, and are the body's primary defense against an infection. Thus the condition of leukopenia places individuals at increased risk of inf ...

thrombocytopenia Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients an ...

, and

anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...

Society and culture

As of March 2018 it was marketed in Japan, China, and South Korea under the brand names Ao Te Min, Arenist, Brecrus, Garesirol, Hustigen, Krix, Lumios, Rizaben, Tramelas, Tranilast, and it was marketed as a

combination drug A combination drug or a fixed-dose combination (FDC) is a medicine that includes two or more active ingredients combined in a single dosage form. Terms like "combination drug" or "combination drug product" can be common shorthand for a FDC prod ...

with

salbutamol Salbutamol, also known as albuterol and sold under the brand name Ventolin among others, is a medication that opens up the medium and large airways in the lungs. It is a short-acting β2 adrenergic receptor agonist which works by causing rel ...

under the brand name Shun Qi. In 2016 the FDA proposed that tranilast be excluded from the list of active pharmaceutical ingredients that

compounding pharmacies In the field of pharmacy, compounding (performed in compounding pharmacies) is preparation of a custom formulation of a medication to fit a unique need of a patient that cannot be met with commercially available products. This may be done for me ...

in the US could formulate with a prescription. Another version of same published a
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Pharmacology

It appears to work by inhibiting the release of histamine from mast cells; it has been found to inhibit proliferation of fibroblasts but its

biological target A biological target is anything within a living organism to which some other entity (like an endogenous ligand or a drug) is directed and/or binds, resulting in a change in its behavior or function. Examples of common classes of biological targets ...

is not known. It has been shown to inhibit the release of many

cytokines Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...

in various cell types, in ''in vitro'' studies. It has also been shown to inhibit

NALP3 NLR family pyrin domain containing 3 (NLRP3) (previously known as NACHT, LRR and PYD domains-containing protein 3 ALP3and cryopyrin), is a protein that in humans is encoded by the ''NLRP3'' gene located on the long arm of chromosome 1. NLRP3 is ...

inflammasome activation and is being studied as a treatment for NALP3-driven inflammatory diseases. It has also been found to block the

ion channel Ion channels are pore-forming membrane proteins that allow ions to pass through the channel pore. Their functions include establishing a resting membrane potential, shaping action potentials and other electrical signals by gating the flow of io ...

TRPV2 TRPV is a family of transient receptor potential cation channels (TRP channels) in animals. All TRPVs are highly calcium selective. TRP channels are a large group of ion channels consisting of six protein families, located mostly on the plasma ...

Chemistry

Tranilast is an analog of a metabolite of tryptophan, and its chemical name is 3′,4′-dimethoxycinnamoyl) anthranilic acid (N-5′). It is almost insoluble in water, easily soluble in dimethylsulfoxide, soluble in dioxane, and very slightly soluble in ether. It is photochemically unstable in solution.

Research

After promising results in three small clinical trials, tranilast was studied in a major clinical trial (the PRESTO trial) by

SmithKline Beecham GSK plc, formerly GlaxoSmithKline plc, is a British multinational pharmaceutical and biotechnology company with global headquarters in London, England. Established in 2000 by a merger of Glaxo Wellcome and SmithKline Beecham. GSK is the tent ...

in partnership with Kissei for prevention of

restenosis Restenosis is the recurrence of stenosis, a narrowing of a blood vessel, leading to restricted blood flow. Restenosis usually pertains to an artery or other large blood vessel that has become narrowed, received treatment to clear the blockage and s ...

after percutaneous transluminal coronary revascularization, but was not found effective for that application. As of 2016, Altacor was developing a formulation of tranilast to prevent of scarring following glaucoma surgery and had obtained an orphan designation from the EMA for this use.

History

It was developed by Kissei and first approved in Japan and South Korea for asthma in 1982, and approved uses for keloid and hypertrophic scars were added later in the 1980s.

References

{{reflist Antiasthmatic drugs Phenol ethers Alkene derivatives Carboxamides Anthranilic acids