FDA Approves Generic for Toxoplasmosis Treatment

The US Food and Drug Administration (FDA) has approved an application for the first generic of Daraprim (pyrimethamine) tablets for the treatment of toxoplasmosis when used with a sulfonamide. The sponsor of the approved generic is Cerovene Inc.

Toxoplasmosis is a caused by a single-celled parasite called Toxoplasma gondii. Infection can cause damage to the brain, eyes or other organs. A Toxoplasma infection can occur as a result of eating undercooked or contaminated food, drinking contaminated water, or by accidental swallowing of the parasite. It is considered to be the leading cause of death attributed to foodborne illness in the United States.

Severe toxoplasmosis is more likely in pregnant women and individuals who have weak immune systems. However, individuals with healthy immune systems may also experience eye damage.

The most common side effects for pyrimethamine include hypersensitivity reactions that can occasionally be severe, including Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme, and hyperphenylalaninemia. These can occur when pyrimethamine is administered at the same time as a sulfonamide. Additionally, when doses of pyrimethamine are used in the treatment of toxoplasmosis, anorexia and vomiting may occur.

Doses used in toxoplasmosis may produce megaloblastic anemia, leukopenia, thrombocytopenia, pancytopenia, neutropenia, atrophic glossitis, hematuria and disorders of cardiac rhythm. However, hematologic effects, can occur at low doses in certain individuals. Pulmonary eosinophilia has been reported rarely.

Pyrimethamine should not be used in patients with known hypersensitivity to pyrimethamine or with documented megaloblastic anemia due to folate deficiency.

A small starting dose is recommended in patients with convulsive disorders to avoid potential nervous system toxicity of pyrimethamine. Additionally, pyrimethamine should be used cautiouslessly in patients with impaired renal or hepatic function or in patients with possible folate deficiency.

“The FDA has a longstanding commitment to increasing competition in markets with limited or no generic alternatives. Through the FDA’s Drug Competition Action Plan, we’ve worked to remove barriers in generic drug development by not only taking actions that improve the efficiency of the development, review and approval of generic drugs, but also by closing loopholes that allow brand-name drug companies to ‘game’ the rules in ways that delay generic competition that Congress intended,” FDA Commissioner Stephen M. Hahn, MD said in the announcement.