Ranganath LR, Psarelli EE, Arnoux JB, et al. - Via performing SONIA 2, a 4-year, open-label, evaluator-blind, randomized, no treatment controlled, parallel-group study, researchers examined the efficacy and safety of once-daily nitisinone for lowering homogentisic acid (HGA) excretion in patients with alkaptonuria. In addition, they examined if nitisinone has a clinical benefit. This study was conducted at three sites in the UK, France, and Slovakia including 138 patients aged 25 years or older with confirmed alkaptonuria and any clinical disease manifestations; participants were randomly assigned (1:1) to receive either oral nitisinone 10 mg daily or no treatment. Participants receiving nitisinone 10 mg daily well tolerated it and had reduction in urinary excretion of HGA. Nitisinone led to a decrease in ochronosis and improvement in clinical signs, indicating a slower progression of the disease.