View clinical trials related to Alkaptonuria.
Filter by:For 28 days, 20 patients with tyrosinaemia will take TYR sphere as part of the usual dietary management of their condition. Patients will record their adherence to recommended intakes each day, gastrointestinal symptoms (if any) experienced each day of weeks one and four, and the palatability of the product at the end of the trial. Metabolic control will be evaluated by dried blood spots collected during the Baseline and End of Study visits, and weekly during the 28 days of the study itself. Trial data will be used in an application to make TYR sphere available via the NHS.
SONIA 1 is an international, multicentre, randomised, open-label, no-treatment controlled, parallel group, dose-response study to investigate the effect of once daily nitisinone on 24-hour urinary homogentisic acid excretion in patients with alkaptonuria after 4-weeks treatment. They study will identify the optimal dose to decrease urine homogentisic acid to near normal levels.
Nitisinone is a potent inhibitor of the enzyme that catalyzes the formation of homogentisic acid, and should be an even more logical treatment for alkaptonuria than for tyrosinemia, for which it has been approved by the FDA.The objective of this research is to explore reported age related differences in toxicity of nitisinone and its pharmacokinetic underpinnings and to develop an optimal therapeutic requirement for a targeted population of presymptomatic patients. The additional effect of mixtures of amino acids excluding tyrosine will be explored to take advantage of protein synthesis to avoid elevations of tyrosine that would otherwise limit the optimal dosage of nitisinone. The study is designed to treat patients and find the optimal dosage of nitisinone to obtain maximal reduction in levels of homogentisic acid and maintain safe levels of tyrosine. The long term objective in the target population of pre-symptomatic patients is the prevention of the characteristic effects on joint cartilage and tendons.
This 3-year study will examine the safety and effectiveness of long-term use of nitisinone (Orfadin) for treating joint problems in patients with alkaptonuria, an inherited disease in which a compound called homogentisic acid accumulates. The excess homogentisic acid causes arthritis and limited joint movement. It can also cause heart valve damage and kidney stones. Patients between 30 and 80 years of age with alkaptonuria may be eligible for this study. Patients must have hip involvement, but at least one remaining hip joint. Candidates are recruited from among patients enrolled in protocol 00-HG-0141, "Clinical, Biochemical, and Molecular Investigations into Alkaptonuria." Participants may enter both protocols simultaneously. Participants are randomly assigned to one of two treatment groups: one group takes their regular medicines plus a 2-mg nitisinone capsule daily; the other group takes only their regular medicines. Patients taking nitisinone have blood tests to measure liver function 2 weeks and 6 weeks after starting treatment. Before starting therapy, all patients are admitted to the NIH Clinical Center for 4-5 days to undergo the following procedures: - Medical history and physical examination - 24-hour urine collection to test for sugar, protein, and other molecules - Blood tests for liver and thyroid function, blood counts, and blood chemistries - Blood and urine tests to measure tyrosine and other amino acids and homogentisic acid - Bone x-rays - Spiral CT (computed tomography) of the abdomen to detect kidney stones - Eye examination and evaluations by specialists in rehabilitation medicine and pain, plus other consults in skin, brain, lung, heart, and kidney, as needed All patients, whether or not they receive nitisinone, return to the Clinical Center for a 2-3 day follow-up admission every 4 months for a history and physical examination, blood tests, and two 24-hour urine collections. Every 12 months (12, 24 and 36 months after starting the study), patients also have repeat bone x-rays, spiral CT, kidney ultrasound, echocardiogram, and electrocardiogram. An Magnetic Resonance Imaging (MRI) of the brain is done at the end of the study. Sixteen months after the end of the study enrollment period, the treated and non-treated groups are evaluated. If nitisinone has delayed the progression of joint disease in the treated group, the study continues and all patients receive the drug for the remainder of the study. If not, the study continues for another 20 months, at which time the study ends and the evaluation process is repeated. Patients who develop symptoms such as corneal crystals, pain, or severe liver or nervous system toxicity may be taken off the study.