nitisinone

Nitisinone is a small molecule drug used primarily to treat hereditary tyrosinemia type 1 (HT-1), a rare autosomal recessive metabolic disorder caused by deficiency of the enzyme fumarylacetoacetate hydrolase. Nitisinone acts as a competitive and reversible inhibitor of the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD), which is involved in the catabolism of tyrosine. By blocking HPPD, nitisinone prevents the formation of toxic metabolites such as maleylacetoacetate and fumarylacetoacetate that would otherwise accumulate due to FAH deficiency and cause liver and kidney toxicity. Treatment with nitisinone must be combined with dietary restriction of tyrosine and phenylalanine to avoid elevated plasma levels of tyrosine. Nitisinone has also been investigated for use in alkaptonuria, another rare metabolic disorder involving defective homogentisic acid oxidase.

Brand names

NityrOrfadin

Other names

2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione