Thiola EC tiopronin 300 mg Tablet, Delayed Release, 90-count — NDC 0178-0901-90 (Billing 00178-0901-90)
This is a package of 90 tablets of Thiola EC tiopronin 300 mg Tablet, Delayed Release from Mission Pharmacal Company, marketed since Jun 2019 and currently FDA-listed. It is this product's only package size.
NDC database record
One package, one record: these facts belong to NDC 0178-0901-90 alone.
- Record
- FDA NDC Directory package listing · Human prescription drug
- Code segments
- 0178 labeler · 0901 product · 90 package
- Package marketed since
- Jun 28, 2019
- Sample package
- No — commercial package
- Listing certified through
- Dec 31, 2026
- Billing quantity
- 90 EA per package
- Barcode (UPC)
- 0301780901908, 0301780902011
- Medicaid fills, this package
- 397 prescriptions in the last four reported quarters
- FDA record last changed
- Jul 24, 2026
Identity & classification
Regulatory identifiers FDA, NLM and CMS codes for this package
Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification
- GSN (GCN sequence number): 079978
- GCN: 46633
- GPI-14 (Medi-Span): 56600050000630
- HICL (First Databank): 003714
- AHFS class code: 92:92.00.00
- RxCUI (RxNorm): 2178075
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 5, 2026
- RxNorm (NLM RxNav) · catalog refreshed Oct 1, 2026
- Medi-Span GPI (licensed)
- First Databank (licensed) · refreshed Oct 1, 2026
RxNorm drug class
This medicine belongs to the Reducing and Complexing Thiol class.
Where does this data come from?
- RxClass (NLM) · catalog refreshed Oct 1, 2026
Clinical
- You have a condition called cystinuria, where your kidneys release too much cystine — a naturally occurring substance — into your urine. When cystine builds up, it forms painful ki...
- What exactly does tiopronin do, and why do I need it?
- Yes — and it depends on which product you have. If you're taking Thiola tablets or regular Tiopronin tablets, take them at least an hour before eating or two hours after a meal. If...
- Does it matter when I take it with food?
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Tiopronin — tap one for details:
Where does this data come from?
- MedlinePlus (NLM) · refreshed Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 5, 2026
Ask a licensed pharmacist directly — free, answered by our team.
Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | $83.27 | $7,494.57 / 90 tablets |
| Medicare drug plans payPart D · quarterly | No Part D plan price is available for this NDC in our data. | |
Where does this data come from?
- CMS NADAC weekly file
- CMS ASP pricing files · refreshed Sep 20, 2026
- CMS Medicaid State Drug Utilization Data · through Q1 2026
- CMS Part D plan pricing files · refreshed Sep 24, 2026
- VA National Acquisition Center price file
Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Marketing end | Status |
|---|---|---|---|---|
| 00178-0901-90 You're viewing this Main listing | 90 TABLET, DELAYED RELEASE in 1 BOTTLE | 2019-06-28 | — | Active |
Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Thiola EC 300 mgthis 00178-0901-90 | Mission | 90 tablets | — | AB | FDA listed | — |
| Tiopronin 300 mg 00254-3035-09 | Par | 90 tablets | — | AB | FDA listed | — |
| Tiopronin 300 mg 00480-7824-98 | Teva | 90 tablets | — | AB | FDA listed | — |
| Tiopronin 300 mg 13668-0692-90 | Torrent | 90 tablets | — | AB | FDA listed | — |
| Tiopronin 300 mg 44523-0055-01 | BioComp | 90 tablets | — | AB | FDA listed | — |
| tiopronin 300 mg 60219-2009-09 | Amneal | 90 tablets | — | — | FDA listed | — |
| Venxxiva 300 mg 70709-0123-90 | Cycle | 90 tablets | — | AB | FDA listed | — |
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA Orange Book · refreshed Oct 3, 2026
- CMS NADAC weekly file
Availability & generic status
The FDA lists approved generic versions of this medicine, but that does not always mean a pharmacy can get one today. Patent rules, launch agreements, supply and pricing can affect when generics actually arrive.
Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.
🛈 What do these terms mean?
- Patent
- Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
- Substance patent
- Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
- Formulation (product) patent
- Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
- Method-of-use patent
- A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
- Skinny label
- A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
- Exclusivity
- FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
- Paragraph IV
- A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
- RLD / RS
- Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
- TE / AB rating
- FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
- LOE (loss of exclusivity)
- The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.
Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.
| Patent | Type | Use code | Expires |
|---|---|---|---|
| US 11458104 ↗ | Method of use | U-3441 | Nov 14, 2038 |
| US 11458104 ↗ | Method of use | U-3441 | Nov 14, 2038 |
| Code | What it grants | Expires |
|---|---|---|
| ODE* | Orphan Drug Exclusivity (7-year) | Jun 28, 2026 |
| ODE* | Orphan Drug Exclusivity (7-year) | Jun 28, 2026 |
Is there a generic version of THIOLA EC 300 MG TABLET?
The FDA approved a generic — why can’t I get it at my pharmacy yet?
Why do different websites show different generic release dates?
What does “FDA listed” mean?
What does a patent or protection date mean here?
What does “current Orange Book estimate” mean?
Can a generic come out before the last patent expires?
Can a generic come out after the listed dates?
What is the difference between patents and exclusivity?
Why are there multiple patent dates?
Where does this data come from?
- FDA Orange Book · refreshed Oct 3, 2026
Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
🧪 Avoiding an ingredient? See Tiopronin inactive ingredients by manufacturer: every current product's list side by side, so you can ask your pharmacy for the version that does not list it.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 2165RE0K14
A plant-based thickener made from cellulose that helps control how quickly the medicine dissolves and releases its active ingredient. It also binds ingredients together and improves the tablet's texture and handling during manufacturing.
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UNII 9XZ8H6N6OH
A plant-based cellulose derivative used as a binder to hold tablet ingredients together, a thickener in liquids, and a coating agent to control how fast the medicine dissolves.
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UNII 3NXW29V3WO
Hypromellose is a plant-based thickener made from cellulose. It's used in medicines as a binder to hold ingredients together, a coating for tablets, and a thickener for liquids.
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UNII EWQ57Q8I5X
Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII NX76LV5T8J
A synthetic plastic polymer made from methacrylic acid and ethyl acrylate. It's used as a coating or binder to control how and where the medicine dissolves in your digestive system.
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UNII 7SEV7J4R1U
A powder made from a naturally occurring mineral. In medicines, talc works as a glidant and anti-caking agent, helping tablets and capsules flow smoothly during manufacturing and preventing clumping.
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UNII 8Z96QXD6UM
Triethyl citrate is a clear liquid derived from citric acid. It acts as a plasticizer and solvent in tablet coatings and film formulations, helping the coating remain flexible and adhere properly to the medicine.
8 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.- FDA label on DailyMed · label index refreshed Oct 5, 2026
- FDA openFDA NDC Directory · synced Oct 1, 2026
Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
Why might an inactive ingredient be missing?
Can inactive ingredients matter?
Manufacturer & labeler
More NDCs from Mission Pharmacal Company labeler code 00178
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- OVACE PLUS SODIUM SULFACETAMIDE 100 mg/mL Liquid NDC 0178-0630-16
- URIBEL TABS Methenamine, Benzoic Acid, Phenyl Salicylate, Methylene Blue, and Hyoscyamine Sulfate .12 mg; 36.2 mg; 81.6 mg; 10.8 mg; 9 mg Tablet, Coated NDC 0178-0745-01
- CitraNatal 90 DHA Vitamin C, Calcium, Iron, Vitamin D3, Vitamin E, Thiamin, Riboflavin, Niacinamide, Vitamin B6, Folic Acid, Iodine, Zinc, Copper, Docusate Sodium 120 mg; 85 mg; 30 [iU]/1; 3 mg; 20 mg; 20 mg; 1 mg; 25 mg; 2 mg; 50 mg; 159 mg Tablet NDC 0178-0821-30
- CitraNatal Assure ascorbic acid, calcium citrate, iron, vitamin d, dl- alpha- tocopherol acetate, thiamine, riboflavin, niacinamide, pyridoxine hydrochloride, folic acid, iodine, zinc, copper, docusate sodium, doconexent and icosapent Kit NDC 0178-0891-30
- Thiola tiopronin 100 mg Tablet, Sugar Coated NDC 0178-0900-01
- Thiola EC tiopronin 100 mg Tablet, Delayed Release NDC 0178-0902-01
- Tindamax tinidazole 250 mg Tablet, Film Coated NDC 0178-8250-40
- Tindamax tinidazole 500 mg Tablet, Film Coated NDC 0178-8500-20
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- Drugs@FDA
Full prescribing information FDA SPL
🎯 Indications and Usage ▾
1 INDICATIONS AND USAGE THIOLA EC is indicated, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation in adults and pediatric patients 20 kg and greater with severe homozygous cystinuria, who are not responsive to these measures alone. THIOLA EC is a reducing and complexing thiol indicated, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation in adults and pediatric patients 20 kg and greater with severe homozygous cystinuria, who are not responsive to these measures alone.
( 1 )
⏱️ Dosage and Administration ▾
2 DOSAGE AND ADMINISTRATION The recommended initial dosage in adult patients is 800 mg/day. In clinical studies, the average dosage was about 1,000 mg/day. ( 2.1 ) The recommended initial dosage in pediatric patients 20 kg and greater is 15 mg/kg/day.
Avoid dosages greater than 50 mg/kg per day in pediatric patients. ( 5.1 , 8.4 ) Measure urinary cystine 1 month after initiation of THIOLA EC and every 3 months thereafter ( 2.3 ) Administer THIOLA EC in 3 divided doses at the same times each day, with or without food. Maintain a routine pattern with regard to meals.
( 2.1 ) THIOLA EC can be crushed and mixed with applesauce. For preparation and administration instructions, see the full prescribing information. ( 2.2 )
2.1Recommended Dosage Adults : The recommended initial dosage in adult patients is 800 mg/day. In clinical studies, the average dosage was about 1,000 mg/day. Pediatrics : The recommended initial dosage in pediatric patients weighing 20 kg and greater is 15 mg/kg/day.
Avoid dosages greater than 50 mg/kg per day in pediatric patients [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.4 )] . Administer THIOLA EC in 3 divided doses at the same times each day, with or without food. Maintain a routine pattern with regard to meals.
Consider starting THIOLA EC at a lower dosage in patients with history of severe toxicity to d-penicillamine.
2.2Preparation and Administration Instructions For patients who cannot swallow the tablet whole, THIOLA EC can be crushed and mixed with applesauce. Administration of THIOLA EC with other liquids or foods has not been studied and is not recommended. Preparation and Administration of THIOLA EC Mixed in Applesauce For patients who can swallow semi-solid food, THIOLA EC can be crushed and mixed with applesauce: Crush the THIOLA EC tablet in a clean pill crusher or mortar and pestle.
Always crush one tablet at a time. Measure approximately one tablespoon of applesauce and transfer it into a container with the crushed THIOLA EC tablet. Mix the crushed THIOLA EC tablet in the applesauce until the powder is well dispersed.
Administer the entire THIOLA EC-applesauce mixture to the patient’s mouth immediately. (However, if this is not possible, the mixture can be stored in a refrigerator for up to 2 hours after adding the crushed tablet to the applesauce. Discard any mixture that has not been given within 2 hours.) To assure that any leftover applesauce mixture from the container is recovered, add tap water to the same container, mix, and have the patient drink the water.
2.3Monitoring Measure urinary cystine 1 month after starting THIOLA EC and every 3 months thereafter. Adjust THIOLA EC dosage to maintain urinary cystine concentration less than 250 mg/L. Assess for proteinuria before treatment and every 3 to 6 months during treatment [see Warnings and Precautions ( 5.1 )] .
Discontinue THIOLA EC in patients who develop proteinuria, and monitor urinary protein and renal function. Consider restarting THIOLA EC treatment at a lower dosage after resolution of proteinuria.
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS AND STRENGTHS Tablets for oral use: 100 mg tablets: round, white to off-white and imprinted in red with “T1” on one side 300 mg tablets: round, white to off-white and imprinted in red with “T3” on one side Tablets: 100 mg and 300 mg ( 3 )
⛔ Contraindications ▾
4 CONTRAINDICATIONS THIOLA EC is contraindicated in patients with hypersensitivity to tiopronin or any other components of THIOLA EC [see Warnings and Precautions ( 5.2 )] . Hypersensitivity to tiopronin or any component of THIOLA EC ( 4 )
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS Proteinuria, including nephrotic syndrome, and membranous nephropathy, has been reported with tiopronin use. Pediatric patients receiving greater than 50 mg/kg of tiopronin per day may be at increased risk for proteinuria. ( 2.1 , 5.1 , 8.4 ) Hypersensitivity reactions have been reported during tiopronin treatment. ( 4 , 5.2 )
5.1Proteinuria Proteinuria, including nephrotic syndrome, and membranous nephropathy, have been reported with tiopronin use. Pediatric patients receiving greater than 50 mg/kg of tiopronin per day may be at increased risk for proteinuria. [see Dosage and Administration ( 2.3 ), Adverse Reactions ( 6.1 , 6.2 ) Use in Specific Populations ( 8.4 )] . Monitor patients for the development of proteinuria and discontinue therapy in patients who develop proteinuria [see Dosage and Administration ( 2.3 )] .
5.2Hypersensitivity Reactions Hypersensitivity reactions (drug fever, rash, fever, arthralgia and lymphadenopathy) have been reported [see Contraindications ( 4 )] .
🤒 Adverse Reactions ▾
6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: Proteinuria [see Warnings and Precautions ( 5.1 )] Hypersensitivity [see Warnings and Precautions ( 5.2 )] Most common adverse reactions (≥10%) are nausea, diarrhea or soft stools, oral ulcers, rash, fatigue, fever, arthralgia, proteinuria, and emesis. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Mission Pharmacal Company at toll-free phone # 1-800-298-1087 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the adverse reaction rates observed in the clinical trials of the drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adverse reactions occurring at an incidence of ≥5% in an uncontrolled trial in 66 patients with cystinuria age 9 to 68 years are shown in the table below. Patients in group 1 had previously been treated with d-penicillamine; those in group 2 had not.
Of those patients who had stopped taking d-penicillamine due to toxicity (34 out of 49 patients in group 1), 22 were able to continue treatment with THIOLA. In those without prior history of d-penicillamine treatment, 6% developed reactions of sufficient severity to require THIOLA withdrawal. Table 1 presents adverse reactions ≥5% in either treatment group occurring in this trial.
Table 1: Adverse Reactions Occurring in One or More Patients System Organ Class Adverse Reaction Group 1 Previously treated with d‑penicillamine (N = 49) Group 2 Naïve to d‑penicillamine (N = 17) Blood and Lymphatic System Disorders anemia 1 (2%) 1 (6%) Gastrointestinal Disorders nausea 12 (25%) 2 (12%) emesis 5 (10%) – diarrhea/soft stools 9 (18%) 1 (6%) abdominal pain – 1 (6%) oral ulcers 6 (12%) 3 (18%) General Disorders and Administration Site Conditions fever 4 (8%) – weakness 2 (4%) 2 (12%) fatigue 7 (14%) – peripheral (edema) 3 (6%) 1 (6%) chest pain – 1 (6%) Metabolism and Nutrition Disorders anorexia 4 (8%) – Musculoskeletal and Connective Tissue Disorders arthralgia – 2 (12%) Renal and Urinary Disorders proteinuria 5 (10%) 1 (6%) impotence – 1 (6%) Respiratory, Thoracic and Mediastinal Disorders cough – 1 (6%) Skin and Subcutaneous Tissue Disorders rash 7 (14%) 2 (12%) ecchymosis 3 (6%) – pruritus 2 (4%) 1 (6%) urticaria 4 (8%) – skin wrinkling 3 (6%) 1 (6%) Taste Disturbance A reduction in taste perception may develop.
It is believed to be the result of chelation of trace metals by tiopronin. Hypogeusia is often self-limited.
6.2Postmarketing Experience Adverse reactions have been reported from the literature, as well as during post-approval use of THIOLA. Because the post-approval 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 THIOLA exposure. Adverse reactions reported during the postmarketing use of THIOLA are listed by body system in Table 2 .
Table 2: Adverse Reactions Reported for THIOLA Pharmacovigilance by System Organ Class and Preferred Term System Organ Class Preferred Term Cardiac Disorders congestive heart failure Ear and Labyrinth Disorder vertigo Gastrointestinal Disorders abdominal discomfort; abdominal distension; abdominal pain; chapped lips; diarrhea; dry mouth; dyspepsia; eructation; flatulence; gastrointestinal disorder; gastroesophageal reflux disease; nausea; vomiting; jaundice; liver transaminitis General Disorders and Administration Site Conditions asthenia; chest pain; fatigue; malaise; pain; peripheral swelling; pyrexia; swelling Investigations glomerular filtration rate decreased; weight increased Metabolism and Nutrition Disorders decreased appetite; dehydration; hypophagia Musculoskeletal and Connective Tissue Disorders arthralgia; back pain; flank pain; joint swelling; limb discomfort; musculoskeletal discomfort; mya… [Excerpted — this section continues on DailyMed.]
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS
7.1Alcohol Tiopronin is released faster from THIOLA EC in the presence of alcohol and the risk for adverse events associated with THIOLA EC when taken with alcohol is unknown. Avoid alcohol consumption 2 hours before and 3 hours after taking THIOLA EC [see Clinical Pharmacology ( 12.3 )] .
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS Lactation: Breastfeeding is not recommended. ( 8.2 ) Geriatric: Choose dose carefully and monitor renal function in the elderly. ( 8.5 )
8.1Pregnancy Risk Summary Available published case report data with tiopronin have not identified a drug-associated risk for major birth defects, miscarriage, or adverse maternal or fetal outcomes. Renal stones in pregnancy may result in adverse pregnancy outcomes (see Clinical Considerations ) . In animal reproduction studies, there were no adverse developmental outcomes with oral administration of tiopronin to pregnant mice and rats during organogenesis at doses up to 2 times a 2 grams/day human dose (based on mg/m 2 ).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively.
Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Renal stones in pregnancy may increase the risk of adverse pregnancy outcomes, such as preterm birth and low birth weight. Data Animal Data No findings of fetal malformations could be attributed to the drug in reproduction studies in mice and rats at doses up to 2 times the highest recommended human dose of 2 grams/day (based on mg/m 2 ).
8.2Lactation Risk Summary There are no data on the presence of tiopronin in either human or animal milk or on the effects of the breastfed child. A published study suggests that tiopronin may suppress milk production. Because of the potential for serious adverse reactions, including nephrotic syndrome, advise patients that breastfeeding is not recommended during treatment with THIOLA EC.
8.4Pediatric Use THIOLA EC is indicated in pediatric patients weighing 20 kg or more with severe homozygous cystinuria, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation who are not responsive to these measures alone. This indication is based on safety and efficacy data from a trial in patients 9 years to 68 years of age and clinical experience. Proteinuria, including nephrotic syndrome, has been reported in pediatric patients.
Pediatric patients receiving greater than 50 mg/kg tiopronin per day may be at greater risk [see Dosage and Administration ( 2.1 , 2.3 ), Warnings and Precautions ( 5.1 ) and Adverse Reactions ( 6.1 )] . THIOLA EC tablets are not approved for use in pediatric patients weighing less than 20 kg [see Dosage and Administration ( 2.1 )] .
8.5Geriatric Use This drug is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
🤰 Pregnancy ▾
8.1Pregnancy Risk Summary Available published case report data with tiopronin have not identified a drug-associated risk for major birth defects, miscarriage, or adverse maternal or fetal outcomes. Renal stones in pregnancy may result in adverse pregnancy outcomes (see Clinical Considerations ) . In animal reproduction studies, there were no adverse developmental outcomes with oral administration of tiopronin to pregnant mice and rats during organogenesis at doses up to 2 times a 2 grams/day human dose (based on mg/m 2 ).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively.
Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Renal stones in pregnancy may increase the risk of adverse pregnancy outcomes, such as preterm birth and low birth weight. Data Animal Data No findings of fetal malformations could be attributed to the drug in reproduction studies in mice and rats at doses up to 2 times the highest recommended human dose of 2 grams/day (based on mg/m 2 ).
🧒 Pediatric Use ▾
8.4Pediatric Use THIOLA EC is indicated in pediatric patients weighing 20 kg or more with severe homozygous cystinuria, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation who are not responsive to these measures alone. This indication is based on safety and efficacy data from a trial in patients 9 years to 68 years of age and clinical experience. Proteinuria, including nephrotic syndrome, has been reported in pediatric patients.
Pediatric patients receiving greater than 50 mg/kg tiopronin per day may be at greater risk [see Dosage and Administration ( 2.1 , 2.3 ), Warnings and Precautions ( 5.1 ) and Adverse Reactions ( 6.1 )] . THIOLA EC tablets are not approved for use in pediatric patients weighing less than 20 kg [see Dosage and Administration ( 2.1 )] .
🧓 Geriatric Use ▾
8.5Geriatric Use This drug is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
🆘 Overdosage ▾
10 OVERDOSAGE There is no information on overdosage with tiopronin.
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action The goal of therapy is to reduce urinary cystine concentration below its solubility limit. Tiopronin is an active reducing agent which undergoes thiol-disulfide exchange with cystine to form a mixed disulfide of tiopronin-cysteine. From this reaction, a water-soluble mixed disulfide is formed and the amount of sparingly soluble cystine is reduced.
12.2Pharmacodynamics The decrement in urinary cystine produced by tiopronin is generally proportional to the dose. A reduction in urinary cystine of 250-350 mg/day at tiopronin dosage of 1 g/day, and a decline of approximately 500 mg/day at a dosage of 2 g/day, might be expected. Tiopronin has a rapid onset and offset of action, showing a fall in cystine excretion on the first day of administration and a rise on the first day of drug withdrawal.
12.3Pharmacokinetics Absorption THIOLA EC Tablets When THIOLA IR and THIOLA EC single doses were given to fasted healthy subjects, the median time to peak plasma levels (T max ) was 1 (range: 0.5 to 2.1) and 3 (range: 1.0 to 6.0) hours, respectively. The peak exposure (C max ) and total exposure (AUC 0-t ) of tiopronin from THIOLA EC tablets were decreased by 22% and 7% respectively compared to THIOLA IR tablets. When THIOLA EC tablets were administered crushed in applesauce, the median time to peak plasma levels of tiopronin (T max ) was 1 hour (range: 0.5 to 2.0) compared to 3.1 hours (range: 1.5 to 4.0) when administered as intact EC tablets.
When THIOLA EC tablets were administered crushed in applesauce, the maximum concentration (C max ) and exposure (AUC 0-t ) to tiopronin were increased by 38% and 14%, respectively, compared to THIOLA EC tablets administered intact. Food Effects Administration of the THIOLA EC tablet with food decreases C max of tiopronin by 13% and AUC 0-t by 25% compared to THIOLA EC administered in a fasted state. Since the drug is dosed to effect, the study results support administration of THIOLA EC tablets with or without food; administer at the same time each day with a routine pattern with regard to meals.
Elimination Excretion When tiopronin is given orally, up to 48% of dose appears in urine during the first 4 hours and up to 78% by 72 hours. Drug Interactions Alcohol An in vitro dissolution study was conducted to evaluate the impact of alcohol (5, 10, 20, and 40%) on the dose dumping of THIOLA EC tablets. The study results showed that the addition of alcohol to the dissolution media increases the dissolution rate of THIOLA EC tablets in the acidic media of 0.1N HCl [see Drug Interactions ( 7.1 )] .
🧬 Mechanism of Action ▾
12.1Mechanism of Action The goal of therapy is to reduce urinary cystine concentration below its solubility limit. Tiopronin is an active reducing agent which undergoes thiol-disulfide exchange with cystine to form a mixed disulfide of tiopronin-cysteine. From this reaction, a water-soluble mixed disulfide is formed and the amount of sparingly soluble cystine is reduced.
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING 100 mg delayed-release, round, white to off-white tablet imprinted with “T1” on one side with red ink and blank on the other side: Bottles of 300 NDC 0178-0902-01. 300 mg delayed-release, round, white to off-white tablet imprinted with “T3” on one side with red ink and blank on the other side: Bottles of 90 NDC 0178-0901-90. Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F) [see USP Controlled Room Temperature] .
📋 Description ▾
11 DESCRIPTION THIOLA EC (tiopronin) delayed-release tablets are a reducing and cystine-binding thiol drug (CBTD) for oral use. Tiopronin is N‑(2‑Mercaptopropionyl) glycine and has the following structure: Tiopronin has the empirical formula C 5 H 9 NO 3 S and a molecular weight of 163.20. In this drug product tiopronin exists as a dl racemic mixture.
Tiopronin is a white crystalline powder, which is freely soluble in water. Each THIOLA EC tablet contains 100 or 300 mg of tiopronin. The inactive ingredients in THIOLA EC tablets include lactose monohydrate, hydroxypropyl cellulose, hydroxypropyl cellulose (low substitute), magnesium stearate, hydroxypropyl methylcellulose E5, methacrylic acid: ethyl acrylate copolymer (Eudragit L 100-55), talc, triethyl citrate.
Tiopronin Chemical Structure
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION Administration Instructions For patients who cannot swallow the tablet whole, the THIOLA EC tablets can be crushed and mixed with applesauce. See Dosage and Administration ( 2.2 ) for preparation and administration instructions. Lactation Advise women that breastfeeding is not recommended during treatment with THIOLA EC [see Use in Specific Populations ( 8.2 )] .
Manufactured and packaged by Mission Pharmacal Company, San Antonio, TX 78230 1355 Distributed by Travere Therapeutics, Inc., San Diego, CA 92130 Copyright© 2024 Mission Pharmacal Company. All rights reserved. L090201R0824 THL_T13768R0924 Image
🧬 Pharmacokinetics ▾
12.3Pharmacokinetics Absorption THIOLA EC Tablets When THIOLA IR and THIOLA EC single doses were given to fasted healthy subjects, the median time to peak plasma levels (T max ) was 1 (range: 0.5 to 2.1) and 3 (range: 1.0 to 6.0) hours, respectively. The peak exposure (C max ) and total exposure (AUC 0-t ) of tiopronin from THIOLA EC tablets were decreased by 22% and 7% respectively compared to THIOLA IR tablets. When THIOLA EC tablets were administered crushed in applesauce, the median time to peak plasma levels of tiopronin (T max ) was 1 hour (range: 0.5 to 2.0) compared to 3.1 hours (range: 1.5 to 4.0) when administered as intact EC tablets.
When THIOLA EC tablets were administered crushed in applesauce, the maximum concentration (C max ) and exposure (AUC 0-t ) to tiopronin were increased by 38% and 14%, respectively, compared to THIOLA EC tablets administered intact. Food Effects Administration of the THIOLA EC tablet with food decreases C max of tiopronin by 13% and AUC 0-t by 25% compared to THIOLA EC administered in a fasted state. Since the drug is dosed to effect, the study results support administration of THIOLA EC tablets with or without food; administer at the same time each day with a routine pattern with regard to meals.
Elimination Excretion When tiopronin is given orally, up to 48% of dose appears in urine during the first 4 hours and up to 78% by 72 hours. Drug Interactions Alcohol An in vitro dissolution study was conducted to evaluate the impact of alcohol (5, 10, 20, and 40%) on the dose dumping of THIOLA EC tablets. The study results showed that the addition of alcohol to the dissolution media increases the dissolution rate of THIOLA EC tablets in the acidic media of 0.1N HCl [see Drug Interactions ( 7.1 )] .
🧬 Pharmacodynamics ▾
12.2Pharmacodynamics The decrement in urinary cystine produced by tiopronin is generally proportional to the dose. A reduction in urinary cystine of 250-350 mg/day at tiopronin dosage of 1 g/day, and a decline of approximately 500 mg/day at a dosage of 2 g/day, might be expected. Tiopronin has a rapid onset and offset of action, showing a fall in cystine excretion on the first day of administration and a rise on the first day of drug withdrawal.
🧪 Nonclinical Toxicology ▾
13 NONCLINICAL TOXICOLOGY
13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis Long-term carcinogenicity studies in animals have not been performed. Mutagenesis Tiopronin was not genotoxic in the chromosomal aberration, sister chromatid exchange, and in vivo micronucleus assays. Impairment of Fertility High doses of tiopronin in experimental animals have been shown to interfere with maintenance of pregnancy and viability of the fetus.
In 2 published male fertility studies in rats, tiopronin at 20 mg/kg/day intramuscular (IM) for 60 days induced reductions in testis, epididymis, vas deferens, and accessory sex glands weights and in the count and motility of cauda epididymal sperm.
📄 Carcinogenesis, Mutagenesis, Impairment of Fertility ▾
13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis Long-term carcinogenicity studies in animals have not been performed. Mutagenesis Tiopronin was not genotoxic in the chromosomal aberration, sister chromatid exchange, and in vivo micronucleus assays. Impairment of Fertility High doses of tiopronin in experimental animals have been shown to interfere with maintenance of pregnancy and viability of the fetus.
In 2 published male fertility studies in rats, tiopronin at 20 mg/kg/day intramuscular (IM) for 60 days induced reductions in testis, epididymis, vas deferens, and accessory sex glands weights and in the count and motility of cauda epididymal sperm.
📄 Recent Major Changes ▾
Dosage and Administration ( 2.2 ) 03/2021
📄 Package Label / Principal Display Panel ▾
Thiola EC ® NDC: 0178-0902-01 Thiola EC ® NDC: 0178-0901-90 Label Label
Medicaid utilization & spend
Medicare Part D spend CMS · PART D · 2026 (Q1)
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