Procysbi 25mg Capsules
It is used to treat nephropathic cystinosis.
Drug Class
Lysosomal Storage Disorder Agent
Pharmacologic Class
Aminothiol Compound; Cystine-Depleting Agent
Pregnancy Category
Category C
FDA Approved
Aug 2013
DEA Schedule
Not Controlled
Overview
What is this medicine?
Procysbi is a medication used to treat a rare genetic disease called nephropathic cystinosis. In this disease, a substance called cystine builds up in different parts of the body, causing damage, especially to the kidneys. Procysbi works by helping to remove this excess cystine from the body's cells, which can slow down the damage and improve kidney function.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely.
Take your medication as directed by your doctor. Swallow the capsule whole - do not chew or crush it.
You can take your medication with fruit juice (except grapefruit juice) or water.
If you have trouble swallowing the capsule, you can sprinkle its contents on up to 1/2 cup (4 ounces/120 mL) of applesauce or berry jelly. Alternatively, you can mix the contents with 1/2 cup (4 ounces/120 mL) of fruit juice (except grapefruit juice). Do not chew the mixture. Take it within 30 minutes of preparing it.
Timing and Food
Take your medication at least 30 minutes before or 2 hours after a meal.
If you need to eat before taking your medication, you can have a small amount of food (about 1/2 cup) within 1 hour before or after taking it.
Always take your medication with a small amount of food or always take it on an empty stomach. Be consistent in your approach.
Avoid eating high-fat foods close to the time you take your medication.
Special Instructions
If you have a feeding tube, you can still take this medication. Follow the instructions provided by your doctor or healthcare provider. Be sure to flush the feeding tube after administering the medication.
If you take other medications, they may need to be taken at a different time than this one. Consult your doctor or pharmacist for guidance on the best schedule.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light and moisture.
Keep it in a dry place, such as a closet or drawer. Do not store it in a bathroom.
Store the medication in its original container, with the lid tightly closed. Do not remove the antimoisture cube or packet.
Missing a Dose
If you miss a dose, take it as soon as you remember.
However, if the next scheduled dose is less than 4 hours away, skip the missed dose and return to your regular schedule.
* Do not take two doses at the same time or take extra doses to make up for a missed one.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely.
Take your medication as directed by your doctor. Swallow the capsule whole - do not chew or crush it.
You can take your medication with fruit juice (except grapefruit juice) or water.
If you have trouble swallowing the capsule, you can sprinkle its contents on up to 1/2 cup (4 ounces/120 mL) of applesauce or berry jelly. Alternatively, you can mix the contents with 1/2 cup (4 ounces/120 mL) of fruit juice (except grapefruit juice). Do not chew the mixture. Take it within 30 minutes of preparing it.
Timing and Food
Take your medication at least 30 minutes before or 2 hours after a meal.
If you need to eat before taking your medication, you can have a small amount of food (about 1/2 cup) within 1 hour before or after taking it.
Always take your medication with a small amount of food or always take it on an empty stomach. Be consistent in your approach.
Avoid eating high-fat foods close to the time you take your medication.
Special Instructions
If you have a feeding tube, you can still take this medication. Follow the instructions provided by your doctor or healthcare provider. Be sure to flush the feeding tube after administering the medication.
If you take other medications, they may need to be taken at a different time than this one. Consult your doctor or pharmacist for guidance on the best schedule.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light and moisture.
Keep it in a dry place, such as a closet or drawer. Do not store it in a bathroom.
Store the medication in its original container, with the lid tightly closed. Do not remove the antimoisture cube or packet.
Missing a Dose
If you miss a dose, take it as soon as you remember.
However, if the next scheduled dose is less than 4 hours away, skip the missed dose and return to your regular schedule.
* Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Take Procysbi exactly as prescribed, usually twice a day, every 12 hours. Do not crush, chew, or open the capsules.
- Swallow capsules whole. If unable to swallow, the capsule can be opened and the contents sprinkled on applesauce or berry puree and consumed immediately.
- Maintain adequate hydration as advised by your doctor.
- Adhere to dietary recommendations, which may include a low-sodium, low-protein diet, as part of cystinosis management.
- Attend all scheduled medical appointments and laboratory tests to monitor your condition and medication effectiveness.
- Report any new or worsening symptoms to your healthcare provider promptly.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Initial dose 6 mg/kg/day divided into two daily doses, administered every 12 hours. Titrate over 4-6 weeks to a maintenance dose of 1.3 g/m²/day or 50 mg/kg/day, whichever is less, divided into two daily doses.
Condition-Specific Dosing:
nephropathicCystinosis:
Initial dose 6 mg/kg/day divided into two daily doses, administered every 12 hours. Titrate over 4-6 weeks to a maintenance dose of 1.3 g/m²/day or 50 mg/kg/day, whichever is less, divided into two daily doses. Max dose 1.95 g/m²/day or 90 mg/kg/day.
Pediatric Dosing
Neonatal:
Not established (safety and efficacy not established in children less than 2 years of age).
Infant:
Not established (safety and efficacy not established in children less than 2 years of age).
Child:
For children 2 years and older: Initial dose 6 mg/kg/day divided into two daily doses, administered every 12 hours. Titrate over 4-6 weeks to a maintenance dose of 1.3 g/m²/day or 50 mg/kg/day, whichever is less, divided into two daily doses. Max dose 1.95 g/m²/day or 90 mg/kg/day.
Adolescent:
Initial dose 6 mg/kg/day divided into two daily doses, administered every 12 hours. Titrate over 4-6 weeks to a maintenance dose of 1.3 g/m²/day or 50 mg/kg/day, whichever is less, divided into two daily doses. Max dose 1.95 g/m²/day or 90 mg/kg/day.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended.
Severe:
No specific dose adjustment recommended. Patients with end-stage renal disease (ESRD) on dialysis may require dose adjustment based on WBC cystine levels.
Dialysis:
Cysteamine is dialyzable. Monitor WBC cystine levels closely and adjust dose as needed. Dosing should be individualized based on patient response and WBC cystine levels.
Hepatic Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended.
Severe:
No specific dose adjustment recommended. Use with caution and monitor for adverse effects.
Pharmacology
Mechanism of Action
Cysteamine is an aminothiol compound that reduces cystine accumulation in cells of patients with cystinosis. It does this by converting cystine into cysteine and cysteine-cysteamine mixed disulfide, both of which can exit the lysosome via the intact lysosomal cysteine transport system. This process depletes intracellular cystine stores.
Pharmacokinetics
Absorption:
Bioavailability:
Not precisely quantified for delayed-release, but designed for sustained absorption.
Tmax:
Approximately 3-4 hours (for delayed-release capsules).
FoodEffect:
Food (high-fat meal) delays Tmax by approximately 2 hours and decreases Cmax by approximately 40%, but does not significantly affect AUC. Can be taken with or without food, but consistency is recommended.
Distribution:
Vd:
Approximately 0.4 L/kg (based on immediate-release data).
ProteinBinding:
Approximately 50% (primarily to albumin).
CnssPenetration:
Limited (low concentrations found in CSF).
Elimination:
HalfLife:
Approximately 4 hours (for delayed-release capsules).
Clearance:
Not precisely quantified.
ExcretionRoute:
Renal (primarily as metabolites).
Unchanged:
<1% (renal excretion of unchanged drug).
Pharmacodynamics
OnsetOfAction:
Reduction in WBC cystine levels typically observed within weeks to months of initiating therapy.
PeakEffect:
Maximal reduction in WBC cystine levels achieved with stable dosing over several months.
DurationOfAction:
Sustained reduction in cystine levels with twice-daily dosing.
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of fluid and electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain or weakness
+ Fast or abnormal heartbeat
+ Severe dizziness or fainting
+ Increased thirst
+ Seizures
+ Feeling extremely tired or weak
+ Decreased appetite
+ Difficulty urinating or changes in urine output
+ Dry mouth
+ Dry eyes
+ Severe stomach upset or vomiting
Ringing in the ears
Dizziness or fainting
Excessive sleepiness
Eye pain
Stomach pain, black or tarry stools, vomiting blood, or coffee ground-like vomit
Upset stomach or vomiting
Decreased appetite
Depression
Raised pressure in the brain, which may cause:
+ Headache
+ Blurred vision
+ Double vision
+ Loss of vision (in some cases, this may be permanent)
Severe skin problems, including:
+ Stretch marks
+ Joint problems
+ Bone problems, such as fractures or deformities
Fibrosing colonopathy, a severe bowel condition, which may cause:
+ Stomach pain
+ Vomiting
+ Weight loss
+ Bloody or prolonged diarrhea
+ Loss of bowel control
Other Possible Side Effects
Most people do not experience severe side effects, and some may have only minor or no side effects at all. However, if you notice any of the following symptoms or if they persist or bother you, contact your doctor or seek medical attention:
Diarrhea
Feeling tired or weak
Changes in body odor
Bad breath
Eye irritation
Flu-like symptoms
Nose or throat irritation
* Ear pain
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of fluid and electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain or weakness
+ Fast or abnormal heartbeat
+ Severe dizziness or fainting
+ Increased thirst
+ Seizures
+ Feeling extremely tired or weak
+ Decreased appetite
+ Difficulty urinating or changes in urine output
+ Dry mouth
+ Dry eyes
+ Severe stomach upset or vomiting
Ringing in the ears
Dizziness or fainting
Excessive sleepiness
Eye pain
Stomach pain, black or tarry stools, vomiting blood, or coffee ground-like vomit
Upset stomach or vomiting
Decreased appetite
Depression
Raised pressure in the brain, which may cause:
+ Headache
+ Blurred vision
+ Double vision
+ Loss of vision (in some cases, this may be permanent)
Severe skin problems, including:
+ Stretch marks
+ Joint problems
+ Bone problems, such as fractures or deformities
Fibrosing colonopathy, a severe bowel condition, which may cause:
+ Stomach pain
+ Vomiting
+ Weight loss
+ Bloody or prolonged diarrhea
+ Loss of bowel control
Other Possible Side Effects
Most people do not experience severe side effects, and some may have only minor or no side effects at all. However, if you notice any of the following symptoms or if they persist or bother you, contact your doctor or seek medical attention:
Diarrhea
Feeling tired or weak
Changes in body odor
Bad breath
Eye irritation
Flu-like symptoms
Nose or throat irritation
* Ear pain
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe nausea, vomiting, or abdominal pain
- Skin rash, lesions, or unusual skin changes
- Bone pain or joint problems
- Unusual tiredness or lethargy
- Headaches, dizziness, or seizures
- Changes in vision or sensitivity to light
- Signs of infection (fever, chills, sore throat)
- Easy bruising or bleeding
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you are breastfeeding, as you should not breastfeed while taking this medication.
To ensure safe treatment, it is crucial to discuss the following with your doctor and pharmacist:
All medications you are currently taking, including prescription and over-the-counter drugs, natural products, and vitamins.
Any existing health problems, as this medication may interact with other drugs or health conditions.
Before making any changes to your medication regimen, consult with your doctor to confirm it is safe to:
Start taking a new medication
Stop taking a medication
* Change the dosage of any medication
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you are breastfeeding, as you should not breastfeed while taking this medication.
To ensure safe treatment, it is crucial to discuss the following with your doctor and pharmacist:
All medications you are currently taking, including prescription and over-the-counter drugs, natural products, and vitamins.
Any existing health problems, as this medication may interact with other drugs or health conditions.
Before making any changes to your medication regimen, consult with your doctor to confirm it is safe to:
Start taking a new medication
Stop taking a medication
* Change the dosage of any medication
Precautions & Cautions
Important Information for Patients Taking This Medication
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent potential interactions with other treatments.
Precautions and Warnings
Avoid operating a vehicle or engaging in activities that require alertness until you understand how this medication affects you.
Regular blood tests will be necessary to monitor your condition. Follow your doctor's instructions for scheduling these tests and discuss any concerns or questions you may have.
Alcohol consumption should be avoided while taking this medication to minimize potential risks.
Be aware that this medication may increase the risk of stomach or bowel ulcers and bleeding. Discuss this risk with your doctor and report any symptoms promptly.
This medication can cause a decrease in white blood cell count, which may increase your risk of infection. Seek immediate medical attention if you experience symptoms such as fever, chills, or sore throat.
A rare but severe skin reaction called toxic epidermal necrolysis can occur. If you experience symptoms like red, swollen, blistered, or peeling skin (with or without fever), red or irritated eyes, or sores in your mouth, throat, nose, or eyes, seek medical help immediately.
Special Considerations
If you become pregnant or suspect you may be pregnant while taking this medication, notify your doctor right away.
For pediatric patients, it is crucial to monitor weight changes, as the dosage of this medication may need to be adjusted. Consult your doctor if your child's weight changes to ensure the correct dose is administered.
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent potential interactions with other treatments.
Precautions and Warnings
Avoid operating a vehicle or engaging in activities that require alertness until you understand how this medication affects you.
Regular blood tests will be necessary to monitor your condition. Follow your doctor's instructions for scheduling these tests and discuss any concerns or questions you may have.
Alcohol consumption should be avoided while taking this medication to minimize potential risks.
Be aware that this medication may increase the risk of stomach or bowel ulcers and bleeding. Discuss this risk with your doctor and report any symptoms promptly.
This medication can cause a decrease in white blood cell count, which may increase your risk of infection. Seek immediate medical attention if you experience symptoms such as fever, chills, or sore throat.
A rare but severe skin reaction called toxic epidermal necrolysis can occur. If you experience symptoms like red, swollen, blistered, or peeling skin (with or without fever), red or irritated eyes, or sores in your mouth, throat, nose, or eyes, seek medical help immediately.
Special Considerations
If you become pregnant or suspect you may be pregnant while taking this medication, notify your doctor right away.
For pediatric patients, it is crucial to monitor weight changes, as the dosage of this medication may need to be adjusted. Consult your doctor if your child's weight changes to ensure the correct dose is administered.
Overdose Information
Overdose Symptoms:
- Severe gastrointestinal upset (nausea, vomiting, diarrhea)
- Lethargy
- Somnolence
- Hypotension
- Seizures
- Bone marrow suppression (rare, with chronic overdose)
What to Do:
Seek immediate medical attention or call Poison Control at 1-800-222-1222. Treatment is supportive and symptomatic.
Drug Interactions
Moderate Interactions
- Didanosine (risk of peripheral neuropathy due to similar adverse effect profiles)
- Drugs that cause gastrointestinal irritation (e.g., NSAIDs, corticosteroids) - increased risk of GI adverse events.
Monitoring
Baseline Monitoring
White Blood Cell (WBC) Cystine Level
Rationale: To establish baseline and guide initial dose titration.
Timing: Prior to initiation of therapy.
Renal Function (serum creatinine, eGFR, urinalysis)
Rationale: To assess baseline kidney function, as cystinosis primarily affects the kidneys.
Timing: Prior to initiation of therapy.
Thyroid Function Tests (TSH, free T4)
Rationale: To assess for hypothyroidism, a common complication of cystinosis.
Timing: Prior to initiation of therapy.
Growth parameters (height, weight)
Rationale: To monitor growth, which is often impaired in cystinosis.
Timing: Prior to initiation of therapy.
Ophthalmologic examination (slit lamp for corneal cystine crystals)
Rationale: To assess for ocular involvement of cystinosis.
Timing: Prior to initiation of therapy.
Routine Monitoring
White Blood Cell (WBC) Cystine Level
Frequency: Every 3-6 months (or more frequently during dose titration).
Target: 0.2-1.0 nmol ½ cystine/mg protein.
Action Threshold: Levels consistently above target range may indicate need for dose adjustment; levels consistently below target range may indicate need for dose reduction to minimize side effects.
Renal Function (serum creatinine, eGFR, urinalysis)
Frequency: Every 3-6 months.
Target: Maintain within patient's baseline or expected range.
Action Threshold: Significant decline in renal function may require further investigation or dose adjustment.
Thyroid Function Tests (TSH, free T4)
Frequency: Annually, or more frequently if symptoms of hypothyroidism develop.
Target: Within normal limits.
Action Threshold: Abnormal results require evaluation and potential thyroid hormone replacement.
Growth parameters (height, weight)
Frequency: Every 3-6 months in children; annually in adults.
Target: Maintain appropriate growth velocity for age.
Action Threshold: Growth failure may indicate inadequate disease control or other complications.
Complete Blood Count (CBC)
Frequency: Annually, or as clinically indicated.
Target: Within normal limits.
Action Threshold: Significant abnormalities may indicate bone marrow suppression or other issues.
Liver Function Tests (ALT, AST, bilirubin)
Frequency: Annually, or as clinically indicated.
Target: Within normal limits.
Action Threshold: Significant abnormalities may indicate liver dysfunction.
Neurological assessment
Frequency: Annually, or as clinically indicated.
Target: Normal neurological function.
Action Threshold: Development of neurological symptoms (e.g., seizures, ataxia, peripheral neuropathy) requires investigation.
Symptom Monitoring
- Gastrointestinal symptoms (nausea, vomiting, abdominal pain, diarrhea, dyspepsia)
- Skin rash or lesions
- Bone or joint pain
- Fatigue
- Changes in vision or photophobia
- Neurological symptoms (e.g., headache, lethargy, seizures, tremors, peripheral neuropathy)
- Signs of hypothyroidism (e.g., weight gain, cold intolerance, constipation, dry skin)
Special Patient Groups
Pregnancy
Use during pregnancy only if the potential benefit justifies the potential risk to the fetus. Cysteamine has shown teratogenic effects in animal studies.
Trimester-Specific Risks:
First Trimester:
Potential for teratogenic effects based on animal data (skeletal abnormalities, cleft palate, omphalocele).
Second Trimester:
Continued potential for fetal harm.
Third Trimester:
Continued potential for fetal harm.
Lactation
It is not known whether cysteamine is excreted in human milk. Due to the potential for serious adverse reactions in the breastfed infant, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
L3 - Moderate risk. Potential for adverse effects in the infant. Monitor for gastrointestinal upset, rash, or other signs of toxicity.
Pediatric Use
Approved for use in children 2 years of age and older. Dosing is weight-based and requires careful titration. Safety and efficacy not established in children younger than 2 years.
Geriatric Use
Clinical studies of Procysbi did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Clinical Information
Clinical Pearls
- Procysbi is a delayed-release formulation designed to be taken every 12 hours, which improves patient adherence compared to immediate-release formulations requiring more frequent dosing.
- Capsules must be swallowed whole. If not possible, contents can be sprinkled on applesauce or berry puree, but must be consumed immediately without chewing.
- Strict adherence to the dosing schedule is crucial for maintaining stable cystine levels and preventing disease progression.
- Regular monitoring of WBC cystine levels is essential for dose adjustment and ensuring therapeutic efficacy.
- Patients should be educated on potential side effects, especially GI upset, and strategies to manage them (e.g., taking with food, dose titration).
- Cysteamine can cause a characteristic 'rotten egg' odor in breath and sweat, which can be a significant social burden for patients. This is due to sulfur-containing metabolites.
Alternative Therapies
- Cysteamine Bitartrate Immediate-Release (Cystagon®) - requires more frequent dosing (every 6 hours).
- Kidney transplantation (for end-stage renal disease due to cystinosis).
- Symptomatic and supportive care (e.g., thyroid hormone replacement, phosphate and vitamin D supplementation, growth hormone, eye drops for corneal crystals).
Cost & Coverage
Average Cost:
Highly variable, typically >$10,000 - $20,000+ per 100 capsules (25mg)
Insurance Coverage:
Specialty Tier (requires prior authorization, often subject to high co-pays or co-insurance)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the overdose, including the medication taken, the amount, and the time it occurred.