Nitisinone Approved for AKU: First FDA Treatment for HGA in Adults
The FDA has approved nitisinone tablets, a meaningful step forward for patients wiht alkaptonuria (AKU). This marks the first-ever FDA-approved treatment for this rare genetic disorder, designed to reduce homogentisic acid (HGA) levels, a primary concern. The medication, marketed as Harliku, targets the underlying cause of AKU. Clinical trials, as highlighted by News Directory 3, revealed improvements in pain, energy, and physical function for those using nitisinone. This breakthrough offers hope for better management of AKU’s long-term effects,including joint problems and cardiac abnormalities. Discover what’s next …
FDA Approves First Treatment for Alkaptonuria (AKU): Nitisinone Tablets
Updated June 19, 2025
The Food and Drug Administration (FDA) has given the green light to nitisinone tablets, marketed as Harliku by Cycle Pharmaceuticals, as the first and only approved treatment for alkaptonuria (AKU) in adult patients. This medication aims to reduce homogentisic acid (HGA) levels in urine, addressing a key factor in the disease.
Alkaptonuria, sometimes called black urine disease, is a rare genetic condition where the body can’t fully break down tyrosine and phenylalanine.This leads to a buildup of HGA, causing urine and body parts to darken. Untreated, AKU can trigger joint pain, reduced mobility, and the need for joint replacements, significantly impacting a patient’s well-being.
Nitisinone works by inhibiting an enzyme involved in tyrosine breakdown, thus reducing HGA production. The FDA’s approval hinged on data from a three-year phase 2 clinical trial. the trial, involving 40 patients aged 30 to 80, compared nitisinone plus regular medication to regular medication alone. While the primary endpoint (hip range of motion) didn’t show significant clinical benefit, other improvements were noted.
The study, published in Molecular Genetics and Metabolism, revealed that patients taking nitisinone experienced improvements in pain, energy levels, and physical functioning, as measured by standard surveys and a six-minute walk test.
Common side effects observed in previous trials included elevated tyrosine levels, keratitis, and thrombocytopenia. More severe, though less common, adverse events could include ocular symptoms, skin plaques, leukopenia, and severe thrombocytopenia.