CurrentCignaPolicy N/A

Metabolic Disorders - Tiopronin Products Prior Authorization Policy

Defines prior authorization requirements and medical necessity criteria for tiopronin products for treatment of cystinuria for Cigna-administered benefit plans.

Policy Summary

PayerCigna

PolicyMetabolic Disorders - Tiopronin Products Prior Authorization Policy

Policy CodePolicy N/A

Change TypeAdded covered product (Venxxiva)

Effective DateN/A

Next Review DateFeb 5, 2025

Key ActionObtain prior authorization and document inadequate response to fluid/diet/alkali measures, confirm cystinuria, and ensure patient weight ≥20 kg.

SourceLink

POLICY UPDATE CHANGES

Added Venxxiva, a branded generic tiopronin delayed-release product, to the Policy; the same criteria apply for all tiopronin products.

≥20 kgminimum patient weight for approval

1 yearauthorization duration

<250 mg/Ltreatment target urinary cystine

Coverage and Indications

FDA-Approved Indication

Covered when ALL of the following are met for cystinuria:

Policy Summary

PayerCigna

PolicyMetabolic Disorders - Tiopronin Products Prior Authorization Policy

Policy CodePolicy N/A

Change TypeAdded covered product (Venxxiva)

Effective DateN/A

Next Review DateFeb 5, 2025

Key ActionObtain prior authorization and document inadequate response to fluid/diet/alkali measures, confirm cystinuria, and ensure patient weight ≥20 kg.

SourceLink

On This Page

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FDA-Approved Indication: Approval for 1 year if ALL A-D are met

A: Patient weighs ≥ 20 kg≥ 20 kg

B: Diagnosis of cystinuria confirmed by laboratory testing (e.g., urinary cystine crystals on microscopy, quantitative urine cystine assay)

C: Patient has had an inadequate response to high fluid intake, dietary modification, and urinary alkalization (per prescriber)

Step therapy requirement

D: Medication prescribed by or in consultation with a nephrologist, urologist, or physician who specializes in the treatment of cystinuria

Specialist prescribing/consultation required

Prior Authorization, Documentation, and Prescriber Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for coverage of Thiola, Thiola EC, and Venxxiva. Approvals are provided for 1 year when criteria are met. Tiopronin products must be prescribed by or in consultation with a nephrologist, urologist, or physician who specializes in the treatment of cystinuria.

Thiola® (tiopronin tablets)
Thiola® EC (tiopronin delayed-release tablets)
Venxxiva® (tiopronin delayed-release tablets)

Step Therapy

Step Therapy / Prerequisite Measures

Approval requires documented inadequate response to conservative measures including high fluid intake, dietary modification (e.g., reduced sodium and animal protein), and urinary alkalization (e.g., increased fruit/vegetable intake or potassium citrate) prior to initiating tiopronin.

Documented trial of high fluid intake (often up to ~4 L/day)
Documented dietary modification (sodium and animal protein restriction)
Documented urinary alkalization attempt (dietary or pharmacologic)

Documentation Required

Required Documentation

Documented confirmation of cystinuria by laboratory testing is required. Examples include: urinary cystine crystals on microscopy or quantitative urine cystine analysis. Also document prescriber specialty and prior conservative therapies tried.

Laboratory confirmation of cystinuria (e.g., urinary cystine crystals or quantitative urine cystine assay)
Documentation of inadequate response to fluid intake, dietary modification, and urinary alkalization
Prescriber is or consulted with a nephrologist, urologist, or cystinuria specialist

Denial Risk

Denial Triggers

Requests may be denied if the criteria for medical necessity are not met or if the use is for any indication considered experimental, investigational, or unproven.

Denial if laboratory confirmation of cystinuria is absent
Denial if conservative measures (fluid, diet, alkalization) not tried or documented
Denial for any use considered experimental, investigational, or unproven

Clinical Background

Cystinuria is an autosomal recessive disorder of abnormal cystine transport that leads to excessive urinary cystine and recurrent formation of kidney, ureter, or bladder stones. Homozygous patients typically have markedly elevated urinary cystine excretion (often >300–400 mg/L/day), and medical management aims to reduce urinary cystine concentration to <250 mg/L to prevent stone formation.

Tiopronin is used, in combination with high fluid intake, urinary alkalization, and dietary modification, to bind cystine and increase its solubility for prevention of recurrent cystine stones in patients who remain symptomatic despite conservative measures.

Key Definitions

Cystinuria

DefinitionCystinuria is an autosomal recessive disorder of abnormal cystine transport leading to excessive urinary cystine and stone formation in the kidney, bladder, and/or ureter.

PrevalenceEstimated prevalence ~1:7,000 to 1:10,000 in the US.

DiagnosisMade clinically based on quantitative urinary cystine assays; genetic testing is not routine.

Tiopronin products

Included productsThiola (tiopronin tablets) — branded/generic formulations.

Delayed‑release formulationsThiola EC (tiopronin delayed‑release) — delayed‑release formulation.

Branded generic delayed‑releaseVenxxiva — branded generic tiopronin delayed‑release supplied in the same dosage strength as Thiola EC.

OpenPayer

Metabolic Disorders - Tiopronin Products Prior Authorization Policy

Coverage and Indications

Patient Parameters & Coding-relevant Criteria

Prior Authorization, Documentation, and Prescriber Requirements

Clinical Background

Key Definitions