suramin

Suramin is a large, highly sulfated, symmetrical organic compound used as a medication to treat human African trypanosomiasis (sleeping sickness) caused by Trypanosoma brucei gambiense and rhodesiense. It is given by intravenous infusion and does not cross the blood–brain barrier, so it is effective only in the early, blood-borne stage of infection rather than in central nervous system involvement.

The precise mechanism of action is not fully understood. Suramin inhibits multiple parasite enzymes and disrupts energy metabolism, particularly glycolysis in the parasite, leading to reduced ATP production. It may also interfere with the parasite’s uptake and use of nutrients.

Pharmacokinetically, suramin is not orally bioavailable; after IV administration it distributes mainly in extracellular fluids and is eliminated slowly by renal and hepatic routes. It has a long duration of action and requires prolonged treatment courses.

Adverse effects include fever, rash, gastrointestinal symptoms, and hypersensitivity reactions. Serious toxicities can involve nephrotoxicity and hepatotoxicity, bleeding disorders due to effects on platelets, and electrolyte disturbances; monitoring of kidney and liver function is recommended during therapy.

History and availability: Suramin was developed in the early 20th century by Bayer and has long been used in the treatment of early-stage sleeping sickness. It is on the World Health Organization's list of essential medicines for specific forms of sleeping sickness.

Research and other uses: Beyond parasitology, suramin has been studied as a research tool to block growth factor signaling and has been investigated for potential anti-angiogenic and anti-neoplastic effects; however its toxicity limits routine clinical use outside human African trypanosomiasis.