"The U.S. Food and Drug Administration today approved Procysbi (cysteamine bitartrate) for the management of nephropathic cystinosis in children and adults. Procysbi was granted orphan product designation because it is intended to treat a rare dis"...
- Clinician Information:
Procysbi Side Effects Center
Medical Editor: Melissa Conrad Stöppler, MD
Procysbi (cysteamine bitartrate) is used to treat a rare genetic condition called nephropathic cystinosis in patients over the age of six years old. It works by depleting levels of the amino acid cysteine. The most common side effects are vomiting, abdominal pain/discomfort, headaches, nausea, diarrhea, decreased appetite, breath odor, fatigue, dizziness, skin odor, and rash.
Procysbi should be prescribed by a physician experienced in management of nephropathic cystinosis. Procysbi capsules should be swallowed whole or after sprinkling on food or in recommended liquids. The total daily dose os Procysbi is 1.3 gram/m2/day in two divided doses, every 12 hours. Procysbi should be taken at least two hours after a meal and at least 30 minutes before eating.
Drug interactions with Procysbi have not been described, but this does not mean that these may not develop. Procysbi has not been studied in pregnant women and should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Breastfeeding is not recommended while taking Procysbi.
Procysbi (cysteamine bitartrate) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What is Prescribing information?
The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.
Procysbi FDA Prescribing Information: Side Effects
The following adverse reactions are also discussed in other sections of the labeling: gastrointestinal ulceration and bleeding, somnolence, encephalopathy, seizures, interstitial nephritis, elevated alkaline phosphatase, and leukopenia [see WARNINGS AND PRECAUTIONS].
Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Causality of side effects is sometimes difficult to determine because adverse effects may result from the underlying disease.
Clinical Trials Experience with Immediate-release Cysteamine
Cysteamine or phosphocysteamine have been administered to 246 children with cystinosis in three clinical trials (the National Collaborative Cysteamine Trial [NCCS], the Long Term Trial, and a trial in the United Kingdom).
The most frequent adverse reactions involved the gastrointestinal and central nervous systems. These were especially prominent at the initiation of cysteamine therapy. Most patients were able to resume therapy at lower doses without incident of adverse reactions.
Adverse reactions were not collected systematically in the NCCS trial that treated 93 children but were often listed by investigators. The following rates may therefore be underestimated. The most common reactions ( > 5%) were vomiting 35%, anorexia 31%, fever 22%, diarrhea 16%, lethargy 11%, and rash 7%. Other adverse reactions included nausea, bad breath, abdominal pain, headache, dizziness, and urticaria.
Withdrawals due to intolerance, vomiting associated with medication, anorexia, lethargy, and fever occurred more frequently in those patients receiving 1.95 grams/m²/day as compared to 1.30 grams/m²/day of immediate-release cysteamine bitartrate.
Clinical Trials Experience with PROCYSBI
The data described below reflect exposure to PROCYSBI in 40 healthy volunteers in 3 clinical trials (Trials 2, 5, and 6) and 72 patients with nephropathic cystinosis in 3 clinical trials (Trials 1, 3 and 4). Healthy volunteers ranged in age from 19 to 64 years old and patients with nephropathic cystinosis ranged in age from 2 to 32 years old. Patients received PROCYSBI at doses ranging 0.5 grams/m²/day to 2.23 grams/m²/day and included 45 males and 27 females. [see Clinical Studies]. The frequency of adverse reactions was similar across trials noting abdominal pain, nausea, and headache as the most commonly reported events in ≥ 5% of individuals in all trials.
The most commonly reported adverse reactions ( ≥ 5%) in healthy volunteers were diarrhea and nausea, abdominal pain /discomfort, headache, vomiting and abnormal urine odor. The most commonly reported adverse reactions ( ≥ 5%) in patients with nephropathic cystinosis, were vomiting, abdominal pain/discomfort, headaches, nausea, diarrhea, anorexia/decreased appetite, breath odor, fatigue, dizziness, skin odor and rash.
There have not been any unexpected serious adverse events (SAEs) reported by patients in clinical trials attributable to PROCYSBI (cysteamine bitartrate) delayed-release capsules. In Trial 3, the pivotal clinical trial comparing PROCYSBI to the immediate-release cysteamine bitartrate, a higher incidence of adverse reactions were reported in patients during the PROCYSBI treatment period compared to the immediate-release cysteamine treatment period (see Table 2). Other significant adverse reactions reported during clinical trials included anaphylaxis and allergic reaction.
TABLE 2: Comparison of adverse reactions that occurred
in 5% or more patients while receiving immediate release cysteamine or PROCYSBI
during Trial 3
|Adverse Reaction||Immediate-release cysteamine
(n = 41)
(n = 43)
|Anorexia/loss of appetite||5||2|
Trial 4 includes patients continuing treatment from Trial 3. In Trial 4, 40 patients have been treated for longer than one year and 3 patients have been treated for at least 19 months. The most commonly reported adverse reactions ( ≥ 5%) were vomiting, abdominal pain, nausea, breath odor, diarrhea, skin odor, and decreased appetite.
The following adverse reactions have been identified during post-approval use of immediate-release cysteamine bitartrate: benign intracranial hypertension (or PTC) with papilledema; skin lesions, molluscoid pseudotumors, skin striae, skin fragility; joint hyperextension, leg pain, genu valgum, osteopenia, compression fracture and scoliosis [see WARNINGS AND PRECAUTIONS].
Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Following the pivotal Phase 3 trial, 40 subjects have been treated for at least one year with PROCYSBI in an Extension Trial. There were no unexpected or serious safety concerns experienced by subjects attributable to PROCYSBI. Based on the average number of gastro-intestinal AEs per subject per month that went slightly downward from 0.11 gastrointestinal disorder AEs/subject/month to ~ 0.09 gastrointestinal disorder AEs/subject/month, there was a gradual decrease in gastrointestinal disorder AEs with long term PROCYSBI therapy (p < 0.05). This decrease was also seen in the average number of total AEs/subject/month; from ~ 0.15 total AEs/subject/month at the beginning of the trial to ~ 0.08 total AEs/subject/month (p < 0.05, post-hoc analysis).
In two randomized clinical trials with healthy volunteers, there were no unexpected serious adverse events reported that were attributable to PROCYSBI. The most frequent adverse events (AEs) reported by the subjects related to PROCYSBI were GI symptoms (16%).. The AE profile for healthy subjects was similar to the AE profile in patients relative to gastro-intestinal disorders (diarrhea and abdominal pain).
Read the entire FDA prescribing information for Procysbi (Cysteamine Bitartrate Delayed-release Capsules) »
Additional Procysbi Information
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