Reducing and Complexing Thiol

Tiopronin

Approved 24 Feb 2023OralTablet, delayed release

The FDA lists this product in 8 strengths and forms.

Indications

Tiopronin delayed-release tablets are indicated, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation in adults and pediatric patients 9 years of age and older with severe homozygous cystinuria, who are not responsive to these measures alone. Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin) delayed release tablets.

However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information. Tiopronin delayed-release tablets are 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 9 years of age and older with severe homozygous cystinuria, who are not responsive to these measures alone.

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Contraindications

Tiopronin delayed-release tablets are contraindicated in patients with hypersensitivity to tiopronin or any other components of tiopronin delayed-release tablets [see Warnings and Precautions ( 5.2 )] . Hypersensitivity to tiopronin or any component of tiopronin delayed-release tablets ( 4 )

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 )] .

Indications

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Warnings and precautions

5.1Proteinuria

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 Endo at 1-800-828-9393 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 tiopronin. In those without prior history of d-penicillamine treatment, 6% developed reactions of sufficient severity to require tiopronin 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 Group 1 Previously treated with Group 2 Naïve to System Organ Class Adverse Reaction d-penicillamine (N = 49) 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 tiopronin. 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 tiopronin exposure. Adverse reactions reported during the postmarketing use of tiopronin are listed by body system in Table 2 .

Table 2: Adverse Reactions Reported for Tiopronin 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; myalgia; neck pain; pain in extremity Nervous System Disorders ageusia; burning sensation; dizziness; dysgeusia; headache; hypoesthesia Renal and Urinary Disorders nephrotic syndrome; proteinuria; renal failure Skin and Subcutaneous Tissue Disorders dry skin; hyperhidrosis; pemphigus foliaceus; pruritus; rash; rash pruritic; skin irritation; skin texture abnormal; skin wrinkling; urticaria

Tiopronin

Indications

Contraindications

Warnings and precautions

5.1Proteinuria

Two medicines in one question?

Tiopronin

Indications

Contraindications

Warnings and precautions

5.1Proteinuria

Two medicines in one question?

5.2Hypersensitivity Reactions

Interactions

7.1Alcohol

Pregnancy and breastfeeding

8.1Pregnancy Risk Summary

Adverse reactions

6.1Clinical Trials Experience

6.2Postmarketing Experience

Composition

Strengths and forms

Official product information

At a glance