NDC 44523-053-01 (billing 44523-0053-01) — Tiopronin 100 mg, 100-count

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

FDA NDC (as labeled) 44523-053-01

Product NDC 44523-053

11-digit billing NDC 44523005301

RxCUI 198287

UNII C5W04GO61S

UPC 0344523053014

Application # NDA019569

SPL Set ID 59e06801-0ef3-29f2-e063-6294a90a4368

Established class (EPC) Reducing and Complexing Thiol

Mechanism of action Cystine Disulfide Reduction

Chemical class N-substituted Glycines

DEA schedule Non-controlled

Marketing category NDA AUTHORIZED GENERIC

Marketing status On market

FDA listing status Listed (active directory)

Marketing start 2026-09-01

Route ORAL

Dosage form TABLET, SUGAR COATED

Substance TIOPRONIN

TE code (Orange Book) AB · RLD · RS

Quick answers

RxCUI (RxNorm): 198287

Why two NDCs? The FDA registers this code as 44523-053-01 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 44523-0053-01. Same drug, same package — only the format differs.

Where does this data come from?

Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

FDA openFDA NDC Directory · synced Oct 1, 2026
FDA label on DailyMed · label index refreshed Oct 1, 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.

Pharmacologic class Reducing and Complexing Thiol

Drug family (ATC) Other urologicals

How it works Cystine Disulfide Reduction

Where does this data come from?

Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

RxClass (NLM) · catalog refreshed Oct 1, 2026

Clinical

📗 Our plain-language guide HelloPharmacist

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?

📖 Read our full Tiopronin guide →

Patient education

📘 MedlinePlus patient leaflet ↗

Supplement & herbal interactions

Some supplements/herbs that may interact with Tiopronin — tap one for details:

Activated CharcoalMajor Coffee CharcoalModerate European MandrakeModerate GlucomannanModerate Guar GumModerate Gum ArabicModerate Slippery ElmModerate TragacanthModerate

🌿 Every supplement checked against Tiopronin (17 interactions) — ranked by severity →

Where does this data come from?

Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

MedlinePlus (NLM) · refreshed Oct 1, 2026
FDA label on DailyMed · label index refreshed Oct 1, 2026

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	No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · quarterly	No Part D plan price is available for this NDC in our data.

ℹ️

No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.

Where does this data come from?

NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

CMS NADAC weekly file
CMS ASP pricing files · refreshed Sep 20, 2026
CMS Medicaid State Drug Utilization Data · refreshed Oct 3, 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
44523-0053-01 You're viewing this Main listing	100 TABLET, SUGAR COATED in 1 BOTTLE	2026-09-01	—	Active

Therapeutic equivalents

Product	Labeler	Pack	NADAC/unit	TE	Status	Price vs. this
Thiola 100 mg 00178-0900-01	Mission	100 tablets	—	AB	FDA listed	—
Tiopronin 100 mg 00093-7909-01	Teva	100 tablets	—	AB	FDA listed	—
Tiopronin 100 mgthis 44523-0053-01	BioComp	100 tablets	—	AB	FDA listed	—

About this product: this is an authorized generic — the brand-name product marketed without its brand name. Other versions are listed above, least expensive first.

Where does this data come from?

Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

FDA openFDA NDC Directory · synced Oct 1, 2026
FDA Orange Book · refreshed Oct 3, 2026
CMS NADAC weekly file

Availability & generic status

🏛️

1988

First FDA approval

Aug 1988

📍

2026

Currently FDA-listed

38 years listed

🔓

·

Listed protection lapsed

listed protections lapsed 2026

🔒Generic approved by FDA, but pharmacy availability is not confirmed

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.

🛡️ Latest patent/protection date listed: The latest listed FDA patent/protection lapsed Jun 2026 — those protections no longer apply, though a generic still needs FDA approval and a manufacturer to market it.

📅 FDA approved Aug 11, 1988 AB TE-rated RLD RS

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.

Patents & exclusivity — FDA Orange Book

Exclusivity ODE-267

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022 2024 2026

Today

LOE

Substance patent Formulation patent Method-of-use patent Exclusivity Pediatric +6mo

🏛️FDA exclusivity

FDA-granted marketing protection. It’s separate from patents and may be shorter than patent protection.

🧪Product / substance patents

Patents covering the active ingredient, product, formulation, or related drug features.

🎯Method-of-use patents

Patents covering specific approved uses. These can sometimes be carved out with a “skinny label,” but not always.

🛈 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.

FDA exclusivity

Code	What it grants	Expires
ODE-267	Orphan Drug Exclusivity (7-year)	Jun 28, 2026

Common questions

Is there a generic version of this drug?

Yes — an FDA-approved generic equivalent is listed in the FDA Orange Book for this drug. See the alternatives section for substitutable, lower-cost products.

The FDA approved a generic — why can’t I get it at my pharmacy yet?

FDA approval and pharmacy availability are two different things. The FDA can approve a generic years before it actually reaches pharmacies, because the brand company may still hold patents or have a settlement that delays the launch. A manufacturer also has to choose to make and sell it, and have supply ready. So a drug can be “FDA-approved generic exists” and still be brand-only at the counter today.

Why do different websites show different generic release dates?

Generic availability is not based on one single date. Some sources use the first exclusivity expiration, some use the last product patent, and others use the latest method-of-use patent. Patent challenges, settlements, licenses, and label carve-outs can also change the real-world launch date. This page shows the underlying Orange Book dates so you can see why estimates may differ.

What does “FDA listed” mean?

It means the product appears in the FDA’s official NDC directory. That’s a good sign a product exists and is intended for the U.S. market, but on its own it does not confirm a pharmacy can fill it today. Where we have recent retail pricing data (NADAC) for a product, we label it “Availability likely” instead.

What does a patent or protection date mean here?

It’s the latest date currently listed in the FDA Orange Book for a patent or exclusivity on the brand product. It can affect when a full generic version becomes widely available — but it is not a guaranteed generic launch date. Generics sometimes arrive earlier (through a settlement or patent challenge) or later (a manufacturer still has to make and sell one).

What does “current Orange Book estimate” mean?

It means we are using the latest patent and exclusivity dates currently listed in the FDA Orange Book. It is not a guaranteed launch date.

Can a generic come out before the last patent expires?

Sometimes. A generic company may challenge a patent, settle with the brand manufacturer, receive a license, or obtain approval with a narrower label that avoids a patented use. In other cases, the last listed protection may delay full-label generic competition.

Can a generic come out after the listed dates?

Yes. Even after patents or exclusivity expire, a generic still needs FDA approval and a manufacturer must choose to market it. Supply, litigation, business decisions, or regulatory issues can delay actual availability.

What is the difference between patents and exclusivity?

Patents are legal protections usually issued by the U.S. Patent and Trademark Office. FDA exclusivity is marketing protection granted by the FDA. They are separate, and either one can affect generic timing.

Why are there multiple patent dates?

One drug can have several patents covering different things: the active ingredient, a formulation, a manufacturing process, or a specific approved use. That is why a page may show several expiration dates instead of one simple generic date.

Built from FDA Orange Book patent and exclusivity data. Dates are refreshed from public FDA data when available; the marker is max(latest patent expiry, latest exclusivity expiry). Paragraph-IV settlements and first-filer 180-day exclusivity can shift the real date; a method-of-use patent may allow an earlier skinny-label generic for non-protected indications. Generic launch timing is an estimate, not a guarantee.

Where does this data come from?

Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

FDA Orange Book · refreshed Oct 3, 2026

What it looks like

Color white

ShapeRound

ImprintM

Size8 mm

ScoringNot scored

One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.

Where does this data come from?

Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

FDA label on DailyMed · label index refreshed Oct 1, 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.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

UNII LMI26O6933
Alumina is a white powder form of aluminum oxide. It's used as a filler to add bulk to tablets and capsules, and sometimes as a thickening or anti-caking agent in powdered formulations.
UNII H0G9379FGK
Calcium carbonate is a white mineral powder used as a filler and buffering agent in medicines. It helps give tablets their bulk and size while neutralizing stomach acid in some formulations.
UNII R12CBM0EIZ
A natural wax derived from a Brazilian palm tree, used as a coating and polish on tablets and capsules. It creates a smooth, shiny finish that protects the medicine and improves appearance.
UNII 905HNO1SIH
A synthetic polymer made from methacrylate compounds that forms a film coating on tablets or capsules. It helps control how quickly the medicine dissolves and releases its active ingredient in the digestive system.
UNII 7Z8S9VYZ4B
Ethylcellulose is a plant-derived thickener and film-former made by chemically modifying cellulose. It's used as a binder to hold tablet ingredients together, a coating to control how quickly medicine is released, or a thickener in liquid formulations.
UNII WZB9127XOA
A synthetic red dye used to color medications and make them easier to identify. It serves as a colorant in tablets, capsules, and liquid formulations.
UNII 66O7AQV0RT
Hydroxypropyl cellulose is a plant-derived thickener and binder made from cellulose. In medicines, it helps hold tablet ingredients together, thickens liquids, and can form a coating on pills or capsules.
UNII J2B2A4N98G
Lactose is a natural sugar derived from milk. In medications, it serves as a filler and binder to add bulk and help hold tablet or capsule ingredients together during manufacturing.
UNII 9B9691B2N9
Magnesium silicate is a mineral compound used in tablets and capsules as a glidant and anti-caking agent. It helps powder ingredients flow smoothly during manufacturing and prevents clumping in the final product.
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.
UNII FZ989GH94E
Povidone is a synthetic polymer made from a plastic-like material. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in your stomach so the medicine can be absorbed.
UNII C151H8M554
A natural sugar derived from sugar cane or sugar beets. It's used as a sweetener, filler, and binder to improve taste, add bulk, and help hold tablet or capsule ingredients together.
UNII 15FIX9V2JP
Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.

13 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?

Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — 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 1, 2026
FDA openFDA NDC Directory · synced Oct 1, 2026

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?

No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.

Why might an inactive ingredient be missing?

Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.

Can inactive ingredients matter?

Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

Manufacturer & labeler

LabelerBioComp Pharma, Inc.

Application holderMISSION PHARMACAL CO

FDA applicationNDA019569 (NDA AUTHORIZED GENERIC)

Labeler code44523

First marketedSep 2026

Product typeHuman Prescription Drug

Portfolio28 products on file

More NDCs from BioComp Pharma, Inc. labeler code 44523

🔎 All NDCs from BioComp Pharma, Inc.

The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).

Where does this data come from?

Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

FDA openFDA NDC Directory · synced Oct 1, 2026
Drugs@FDA

Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Very long sections are excerpted here and marked; the full text is on DailyMed (linked in the sources below). Jump with a chip, search within the label, or expand everything.

🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 👥 Use in Specific Populations 🆘 Overdosage 🧬 Clinical Pharmacology 📦 How Supplied / Storage and Handling 📋 Description 🧪 Nonclinical Toxicology 📄 Package Label / Principal Display Panel

🎯 Indications and Usage 94 words ▾

1 INDICATIONS AND USAGE Tiopronin 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 20 kg and greater with severe homozygous cystinuria, who are not responsive to these measures alone. Tiopronin 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 20 kg and greater with severe homozygous cystinuria, who are not responsive to these measures alone.

(1)

⏱️ Dosage and Administration ~2 min read ▾

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. (2.1, 5.1, 8.4) Administer Tiopronin Tablets in 3 divided doses at the same times each day at least one hour before or 2 hours after meals. (2.1) Measure urinary cystine 1 month after initiation of Tiopronin Tablets and every 3 months thereafter.

(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 Tiopronin Tablets in 3 divided doses at the same times each day at least one hour before or 2 hours after meals. Consider starting Tiopronin Tablets at a lower dosage in patients with history of severe toxicity to d-penicillamine.

2.2Monitoring Measure urinary cystine 1 month after starting Tiopronin Tablets and every 3 months thereafter. Adjust Tiopronin Tablets 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)].

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 Tiopronin Tablets in 3 divided doses at the same times each day at least one hour before or 2 hours after meals. Consider starting Tiopronin Tablets at a lower dosage in patients with history of severe toxicity to d-penicillamine.

2.2Monitoring Measure urinary cystine 1 month after starting Tiopronin Tablets and every 3 months thereafter. Adjust Tiopronin Tablets 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)].

💊 Dosage Forms and Strengths 27 words ▾

3 DOSAGE FORMS AND STRENGTHS Tablets for oral use: 100 mg tablets: round, white and imprinted in red with “M” on one side Tablets: 100 mg (3)

⛔ Contraindications 34 words ▾

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

⚠️ Warnings and Cautions 218 words ▾

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 (2.2), 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 (2.2)].

5.2Hypersensitivity Reactions Hypersensitivity reactions (drug fever, rash, fever, arthralgia and lymphadenopathy) have been reported [see Contraindications (4)].

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 (2.2), 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 (2.2)].

5.2Hypersensitivity Reactions Hypersensitivity reactions (drug fever, rash, fever, arthralgia and lymphadenopathy) have been reported [see Contraindications (4)].

🤒 Adverse Reactions ~1 min read ▾

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 BioComp Pharma, Inc. at 1-866-762-2365 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.

6.2Postmarketing Experience Adverse reactions have been reported from the literature, as well as during post-approval use of Tiopronin Tablets. 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 Tablets exposure. Adverse reactions reported during the postmarketing use of Tiopronin Tablets are listed by body system in Table 2. image

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.

6.2Postmarketing Experience Adverse reactions have been reported from the literature, as well as during post-approval use of Tiopronin Tablets. 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 Tablets exposure. Adverse reactions reported during the postmarketing use of Tiopronin Tablets are listed by body system in Table 2. image

👥 Use in Specific Populations ~3 min read ▾

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) See 17 for PATIENT COUNSELING INFORMATION. Revised: 05/2021

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 Tiopronin Tablets.

8.4Pediatric Use Tiopronin Tablets are 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, 2.2), Warnings and Precautions (5.1) and Adverse Reactions (6.1)]. Tiopronin Tablets are not approved for use in pediatric patients weighing less than 20 kg or in pediatric patients unable to swallow tablets [see Recommended Dosage (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.

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… [Excerpted — this section continues on DailyMed.]

🆘 Overdosage 10 words ▾

10 OVERDOSAGE There is no information on overdosage with tiopronin.

🧬 Clinical Pharmacology ~2 min read ▾

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 tiopronincysteine. 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 Tiopronin Tablets When Tiopronin Tablets single doses were given to fasted healthy subjects (n = 39), the median time to peak plasma level (T max ) was 1 (range: 0.5 to 2.1) hours. 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.

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 Tiopronin Tablets When Tiopronin Tablets single doses were given to fasted healthy subjects (n = 39), the median time to peak plasma level (T max ) was 1 (range: 0.5 to 2.1) hours. 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.

📦 How Supplied / Storage and Handling 44 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING 100 mg round, white, immediate-release tablet imprinted in red with “M” on one side and blank on the other side: Bottles of 100 NDC 44523-053-01. Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F) [see USP Controlled Room Temperature].

📋 Description ~1 min read ▾

11 DESCRIPTION Tiopronin immediate-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: 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 Tablets. In those without prior history of d-penicillamine treatment, 6% developed reactions of sufficient severity to require Tiopronin Tablets withdrawal. Table 1 presents adverse reactions ≥5% in either treatment group occurring in this trial.

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.

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 Tiopronin Tablet contains 100 mg of tiopronin. The inactive ingredients in Tiopronin Tablets include calcium carbonate, carnauba wax, ethyl cellulose, dimethylaminoethyl methacrylate: butyl methacrylate: methyl methacrylate copolymer (Eudragit E 100), hydroxy-propyl cellulose, lactose monohydrate, magnesium stearate, povidone, sugar, talc, titanium dioxide. Image Image

🧪 Nonclinical Toxicology 99 words ▾

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.

📄 Package Label / Principal Display Panel 21 words ▾

L05301R0626 Manufactured for: BioComp Pharma, Inc. by Mission Pharmacal Company San Antonio, TX 78230 BCP_T14258R0726 Image

Tiopronin Tablets 100 mg Label

Glossary — plain-language definitions of medical terms used in this label:

case report: A written account of what happened to one patient, useful as a signal but not proof of cause.

contraindicated: Should not be used in that situation, because the risk is considered too high.

in vivo: In a living person or animal rather than in a laboratory dish.

Absorption: How a medicine moves from where it is taken, such as the stomach or gut, into the bloodstream.

adverse reaction: An unwanted or harmful effect that a medicine causes in the body.

Adverse Reactions: Unwanted or harmful effects that people experienced while taking a medicine, listed on its official label.

animal reproduction studies: Tests in pregnant animals used to check whether a medicine might harm a developing baby.

arthralgia: Joint pain.

Carcinogenesis, Mutagenesis, Impairment of Fertility: A label section reporting whether lab or animal studies found effects on cancer risk, genes, or the ability to have children.

Clinical Pharmacology: The label section explaining how a medicine works in the body and how the body processes it.

Clinical Studies: The label section summarizing the research trials used to show that a medicine works and is acceptably safe.

Contraindications: A list of situations or health conditions in which a medicine should not be used because the chance of harm is too high.

diarrhea: Loose, watery bowel movements that happen more often than normal.

Dosage and Administration: The label section explaining how much of a medicine to use and how to take or give it.

efficacy: How well a treatment works under the controlled conditions of a clinical study.

Elimination: The overall removal of a medicine from the body by breaking it down and passing it out.

emesis: The medical word for vomiting, or bringing up the contents of the stomach through the mouth.

estimated background risk: The normal chance that any pregnancy will have a birth defect or problem, even without taking any medicine.

Excretion: How the body removes a medicine or its leftover pieces, mainly through the urine or stool.

fertility: The natural ability to become pregnant or to father a child.

How Supplied/Storage and Handling: The label section describing the forms and strengths a medicine comes in and how to store it properly.

hypersensitivity: An overreaction of the body's defense system to a substance, causing symptoms such as rash, swelling, or trouble breathing.

immediate-release: A standard pill or capsule that releases all of its medicine soon after it is swallowed.

incidence: How often a new event, such as a side effect, happens in a group of people over a set period of time.

Indications and Usage: The label section stating which medical conditions the FDA has officially approved the medicine to treat, prevent, or manage.

intramuscular: An injection given deep into a muscle; often written as IM.

lactation: The making and release of milk from a mother's breasts after giving birth.

lymphadenopathy: Swollen or enlarged lymph nodes, often felt as lumps in the neck, armpits, or groin.

Mechanism of Action: How a medicine produces its effect in the body, described at the level of cells or body chemistry.

NDC: A unique number that identifies a specific medicine, its maker, strength, and package size.

Nonclinical Toxicology: The label section summarizing safety findings from laboratory and animal studies, rather than from studies in people.

organogenesis: The early stage of pregnancy when the developing baby's organs are first forming.

Overdosage: The label section describing what can happen if too much of a medicine is taken and how it may be treated.

Patient Counseling Information: The label section telling health professionals what to explain to patients about using a medicine safely.

Pharmacokinetics: The study of how the body takes in a medicine, spreads it around, breaks it down, and removes it over time.

preterm birth: Birth of a baby earlier than usual, before 37 weeks of pregnancy.

proteinuria: Protein leaking into the urine, which can be a sign that the kidneys' filters are damaged.

Use in Specific Populations: The label section describing how a medicine affects particular groups, such as pregnant people, children, or older adults.

Warnings and Precautions: The label section describing serious risks to know about and safety steps to follow while using a medicine.

withdrawal: Uncomfortable physical or mental symptoms that appear when a medicine the body has gotten used to is reduced or stopped.

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Tiopronin — the program that covers self-administered drugs. 3 manufacturers.

⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Tiopronin. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.

Period

Total Part D spend

$441.5K

Claims incl. refills

99

Beneficiaries

42

Spend / beneficiary

$10,511.18

Spend / claim

$4,459.29

Trend by period

💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Tiopronin — the ingredient across all brands.

Top reported reactions

Nausea194

Rash129

Fatigue121

Pain118

Pyrexia116

Nephrolithiasis92

Arthralgia85

Age at onset

Child1

Adolescent5

Adult83

Elderly25

Reporter sex

Serious outcomes

Hospitalization308

Death88

Life-threatening42

Disabling8

Reports over time (by year) — tap or hover for the count & year

Most recent year is provisional (FAERS lags ~3 months).

Where does this data come from?

Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

FDA Adverse Event Reporting System (FAERS)

About this NDC listing & data coverage

Finished prescription product

What data is (and isn’t) available for this NDC — tap to expand

NDC identity (package / product / labeler codes)	✓ Available
Labeler	✓ Available
Product & package description	✓ Available
Marketing category & status	✓ Available
Active ingredient / dosage form / route	✓ Available
FDA label (SPL via DailyMed)	✓ Available
Package photos	✓ Available
Inactive ingredients (structured)	✓ Available
NADAC pharmacy acquisition price (CMS)	— Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data	✓ Available
HCPCS J-code billing crosswalk	— Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD)	— Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.

“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?

The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.

Is the NDC printed on the package the same as the 11-digit billing NDC?

Yes, they identify this exact package in different formats. The form printed on the packaging and shown on DailyMed is the one the FDA registered. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero and the dashes are dropped. The Identity section at the top of this page lists each form of this code.

Is this package still being marketed?

Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by BioComp Pharma, Inc.. Listing status can change — the directory data on this page refreshes weekly.

Who lists this product with the FDA?

BioComp Pharma, Inc. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.

Do I need a prescription for this product?

This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.

This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.

Where does this data come from?

Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

Related NDC lookups

🧪 All Tiopronin NDCsSame ingredient 🏭 All BioComp labeler NDCsLabeler code 44523 📚 All Reducing and Complexing Thiol NDCsDrug class 📖 Read the Tiopronin drug informationUses, warnings & side effects

Tiopronin 100 mg Tablet, Sugar Coated, 100-count — NDC 44523-053-01 (Billing 44523-0053-01)

NDC database record

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

RxNorm drug class

Clinical

Patient education

Supplement & herbal interactions

Pricing

Packaging — all sizes for this product

Therapeutic equivalents

Availability & generic status

What it looks like

Inactive Ingredients / Excipients

Inactive ingredient FAQ

Manufacturer & labeler

More NDCs from BioComp Pharma, Inc. labeler code 44523

Full prescribing information FDA SPL

12 CLINICAL PHARMACOLOGY

13 NONCLINICAL TOXICOLOGY

Medicare Part D spend CMS · PART D · 2026 (Q1)

Reported adverse events (FAERS)

Top reported reactions

Age at onset

Reporter sex

Serious outcomes

About this NDC listing & data coverage

Questions about this listing