Tolvaptan, sold under the brand name Samsca among others, is an aquaretic drug that functions as a selective,

competitive Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...

vasopressin receptor 2 (V₂) antagonist used to treat

hyponatremia Hyponatremia or hyponatraemia is a low concentration of sodium in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be abs ...

(low blood

sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...

levels) associated with

congestive heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, a ...

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repai ...

, and the syndrome of inappropriate antidiuretic hormone (SIADH). Tolvaptan was approved by the U.S.

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA) on May 19, 2009, and is sold by

Otsuka Pharmaceutical Co. (), abbreviated OPC, is a pharmaceutical company headquartered in Tokyo, Osaka and Naruto, Japan. The company was established August 10, 1964. History OPC's parent company Otsuka Holdings Co. Ltd. joined the Tokyo Stock Exchange through an in ...

under the trade name Samsca. Tolvaptan, as Jynarque, was granted approval for medical use in the United States in April 2018. The U.S.

(FDA) granted tolvaptan a

fast track The fast track is an informal English term meaning "the quickest and most direct route to achievement of a goal, as in competing for professional advancement". By definition, it implies that a less direct, slower route also exists. Fast track or F ...

designation for clinical trials investigating its use for the treatment of

polycystic kidney disease Polycystic kidney disease (PKD or PCKD, also known as polycystic kidney syndrome) is a genetic disorder in which the renal tubules become structurally abnormal, resulting in the development and growth of multiple cysts within the kidney. These c ...

. The FDA granted Jynarque an

orphan drug An orphan drug is a pharmaceutical agent developed to treat medical conditions which, because they are so rare, would not be profitable to produce without government assistance. The conditions are referred to as orphan diseases. The assignment of ...

designation in April 2012, for the treatment of autosomal dominant polycystic kidney disease. Tolvaptan is available as a

generic medication A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active ch ...

Medical uses

Tolvaptan (Samsca) is indicated for the treatment of clinically significant hypervolemic and euvolemic hyponatremia. Tolvaptan (Jynarque) is indicated to slow kidney function decline in adults at risk of rapidly progressing autosomal dominant polycystic kidney disease (ADPKD). Tolvaptan phosphate is a

prodrug A prodrug is a medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be used to improve how the drug ...

of tolvaptan, developed for

intravenous administration Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutri ...

. Tolvaptan phosphate is converted into the active drug tolvaptan in the human body following administration.

Side effects

The FDA has determined that tolvaptan should not be used for longer than 30 days and should not be used in patients with underlying liver disease because it can cause liver injury, potentially leading to liver failure. When using to treat hyponatremia, it may cause too rapid correction of

resulting in fatal

osmotic demyelination syndrome Central pontine myelinolysis is a neurological condition involving severe damage to the myelin sheath of nerve cells in the ''pons'' (an area of the brainstem). It is predominately iatrogenic (treatment-induced), and is characterized by acute par ...

Pharmacology

Tolvaptan is a selective vasopressin V₂ receptor antagonist.

Chemistry

Tolvaptan is a

racemate In chemistry, a racemic mixture, or racemate (), is one that has equal amounts of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. ...

, a 1:1 mixture of the following two enantiomers:Rote Liste Service GmbH (Hrsg.): ''Rote Liste 2017 - Arzneimittelverzeichnis für Deutschland (einschließlich EU-Zulassungen und bestimmter Medizinprodukte)''. Rote Liste Service GmbH, Frankfurt/Main, 2017, Aufl. 57, , S. 222.

References

External links