biostudies-literatureOlsson BEuropean Research Council41-49https://www.ebi.ac.uk/biostudies/studies/S-EPMC8743336biostudies-literatureUnknown63(1)In an open-label, controlled study of nitisinone in alkaptonuria (SONIA 2), patients were advised to lower dietary protein intake to reduce serum tyrosine (s-Tyr) levels and the risk of keratopathy. A body weight increase was observed in the nitisinone-treated patients but not in the control group. To investigate the effectiveness and consequence of protein restriction in patients with alkaptonuria, a post-hoc analysis of SONIA 2 was performed. One hundred and thirty-eight patients were randomised (nitisinone: n = 69, controls: n = 69). Comparison of baseline and Month 12 data on 24-h urinary excretion of HGA (u-HGA₂₄) and urea (u-urea₂₄, used as an approximate protein intake measure), tyrosine and body weight were performed using paired <i>t</i> tests. Comparisons ofJIMD reportsEffects of a protein-restricted diet on body weight and serum tyrosine concentrations in patients with alkaptonuria.PMC8743336304985Milan AArnoux JBRanganath LImrich RRudebeck MOlsson BfalseEffects of a protein-restricted diet on body weight and serum tyrosine concentrations in patients with alkaptonuria.In an open-label, controlled study of nitisinone in alkaptonuria (SONIA 2), patients were advised to lower dietary protein intake to reduce serum tyrosine (s-Tyr) levels and the risk of keratopathy. A body weight increase was observed in the nitisinone-treated patients but not in the control group. To investigate the effectiveness and consequence of protein restriction in patients with alkaptonuria, a post-hoc analysis of SONIA 2 was performed. One hundred and thirty-eight patients were randomised (nitisinone: n = 69, controls: n = 69). Comparison of baseline and Month 12 data on 24-h urinary excretion of HGA (u-HGA₂₄) and urea (u-urea₂₄, used as an approximate protein intake measure), tyrosine and body weight were performed using paired <i>t</i> tests. Comparisons of2022-01-01T00:00:00Z2022 Jan2026-05-07T20:18:44.898Z2022-02-11T16:17:00.053ZS-EPMC87433363502827010.1002/jmd2.12255