Cystinosis (CTNS) Clinical Trials and Treatments

Cells break down proteins inside small compartments called lysosomes, and a transporter called cystinosin carries the amino acid cystine back out. Changes in the CTNS gene, which makes cystinosin, trap cystine inside, where it forms crystals in the kidneys, eyes, thyroid, muscles and other organs. In the infant form the kidneys' filtering tubes fail first, so the body loses water, salts and minerals, children grow poorly and the kidneys fail by about age 10 without treatment.

The most common symptoms of Cystinosis include Heavy urination, thirst and dehydration, as the kidneys lose salts and minerals (renal Fanconi syndrome), Poor growth and soft, bowed bones, Eye pain and sensitivity to light from crystals in the cornea, Kidney failure, by about age 10 without treatment in the infant form, An underactive thyroid, in about half of affected children by age 10. About 1 in 100,000 to 200,000 newborns worldwide (MedlinePlus Genetics), and about 1 in 26,000 in Brittany, France. GeneReviews notes that cystinosis causes about 5% of kidney failure in children.. Symptoms can range from mild to severe and may vary between individuals.

Trial Friend lists all active clinical trials for Cystinosis from ClinicalTrials.gov, with eligibility criteria translated into plain English. Patients can filter by trial phase and recruitment status, search by location, and use the Match Me tool to score trials against their profile. As of October 12, 2026, ClinicalTrials.gov lists 9 open cystinosis studies, 4 of them testing a treatment.

Yes. As of September 2026, Trial Friend lists 4 FDA-approved drugs used to treat Cystinosis: Cystagon (cysteamine bitartrate), first approved in 1994; Cystaran (cysteamine hydrochloride ophthalmic solution 0.44%), first approved in 2012; Procysbi (cysteamine bitartrate delayed-release), first approved in 2013; and Cystadrops (cysteamine ophthalmic solution 0.37%), first approved in 2020.

Each has its own page with what the label covers, side effects and how it is given, and the Treatments section of this page adds any further approved drugs found in FDA labeling data.

Cystinosis is caused by variants in the CTNS gene. A large deletion of 57,000 DNA letters accounts for more than half of CTNS variants in people of northern European ancestry (GeneReviews).

It is inherited in an autosomal recessive pattern: both parents are usually unaffected carriers, and each pregnancy has a 1 in 4 chance of an affected child. About 1 in 100,000 to 200,000 newborns worldwide (MedlinePlus Genetics), and about 1 in 26,000 in Brittany, France. GeneReviews notes that cystinosis causes about 5% of kidney failure in children. Genetic testing confirms the diagnosis.

Yes. Genetic testing for Cystinosis looks at the CTNS gene. A large deletion of 57,000 DNA letters accounts for more than half of CTNS variants in people of northern European ancestry (GeneReviews).

It is inherited in an autosomal recessive pattern: both parents are usually unaffected carriers, and each pregnancy has a 1 in 4 chance of an affected child.

A confirmed variant establishes the diagnosis and is often required to enroll in gene-specific trials. The labs currently offering the test are listed in the Genetic Testing section of this page, pulled live from the NIH Genetic Testing Registry. A genetic counselor can help interpret the result and decide which relatives should be tested.

Eligibility for Cystinosis clinical trials depends on factors like age, diagnosis, treatment history, and overall health. Each trial sets its own inclusion and exclusion criteria. Trial Friend translates these requirements from medical language into plain English so patients can review them more easily. The Match Me tool can score your profile against active trials to help identify studies that may be a fit.

Participating in a Cystinosis clinical trial typically involves scheduled visits, medical tests, and close monitoring by a research team. Depending on the study phase, you may receive an investigational treatment, a placebo, or the current standard of care. Trials may last from a few weeks to several years. Study participation is voluntary, and you can withdraw at any time.