Skip to main content


Generic name: sparsentan
Dosage form: tablets
Drug class: Miscellaneous cardiovascular agents

Medically reviewed by Judith Stewart, BPharm. Last updated on Aug 23, 2023.

What is Filspari?

Filspari is a prescription medicine used to reduce levels of protein in the urine (proteinuria) in adults with a kidney disease called primary immunoglobulin A nephropathy (IgAN).

Filspari is a Dual Endothelin Angiotensin Receptor Antagonist (DEARA) that works by targeting two pathways (endothelin-1 and angiotensin II) that are involved in the progression of IgAN.

What is Filspari used to treat?

Filspari is used to treat IgA nephropathy (IgAN), the most common type of primary glomerulonephritis and a leading cause of kidney failure due to glomerular disease. It is used in people at risk of rapid disease progression.

IgA nephropathy is a rare, progressive kidney disease characterized by the buildup of the protein immunoglobulin A (IgA) in the kidneys. The depostis of IgA cause a breakdown of the normal filtering mechanisms in the kidney, leading to hematuria (blood in the urine), proteinuria (protein in the urine), and a progressive loss of kidney function. Other symptoms of IgAN may include edema (swelling) and hypertension (high blood pressure).

Filspari is approved to reduce proteinuria in adults with primary IgAN who are at risk of rapid disease progression. This indication was granted under accelerated approval based on reduction in proteinuria. It has not been established whether Filspari slows kidney function decline in patients with IgAN. Continued approval may be contingent upon confirmation of clinical benefit in an ongoing clinical study.

It is not known if this medicine is safe and effective in children.

Important information

Filspari is only available through the Filspari REMS Program.
Before you start treatment, you must read and agree to all of the instructions in the Filspari REMS Program.

Filspari can cause serious side effects, including:

Liver problems.

Serious birth defects.

Filspari can cause serious birth defects if taken during pregnancy.

Patients who can become pregnant must use effective birth control during treatment with Filspari and for 1 month after stopping Filspari because the medicine may still be in your body.

See the chart below for acceptable birth control options during treatment with Filspari.

effective birth control options

Who should not take Filspari?

Do not take Filspari if you:

Ask your healthcare provider if you are not sure if you take one of these medicines.

Before taking Filspari

Before you take Filspari, tell your healthcare provider about all of your medical conditions, including if you have:

What other drugs will affect Filspari?

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, herbal supplements and grapefruit. Filspari and other medicines may affect each other and cause side effects.

You should not take Filspari if you are taking any of these medicines:

Especially tell your healthcare provider if you take:

This is not a complete list of all the medicines that may interact with Filspari. Do not start any new medicine until you check with your healthcare provider.

How should I take Filspari?

Dosing information

Usual Adult Dose for IgA Nephropathy:

200 mg orally once daily for 14 days, then 400 mg once daily, as tolerated.

- prior to initiating treatment, discontinue use of renin-angiotensin-aldosterone system (RAAS) inhibitors, endothelin receptor antagonists (ERAs) or aliskiren.

- to reduce proteinuria in adults with primary immunoglobulin A nephropathy (IgAN) at risk of rapid disease progression, generally a urine protein-to-creatinine ratio (UPCR) ≥1.5 g/g. This indication is approved under accelerated approval based on reduction of proteinuria. It has not been established whether Filspari slows kidney function decline in patients with IgAN. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory clinical trial.

What should I avoid while taking Filspari?

Filspari side effects

Filspari can cause serious side effects, including:

The most common side effects include:

These are not all the possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store Filspari?

Keep all medicines out of the reach of children and pets.

General information about the safe and effective use of Filspari

Medicines are sometimes prescribed for purposes other than those listed in the Medication Guide. Do not use this medicine for a condition for which it was not prescribed. Do not give it to other people, even if they have the same symptoms that you have. It may harm them. You can ask your healthcare provider or pharmacist for information that is written for health professionals.

What are the ingredients in Filspari?

Active ingredient: sparsentan
Inactive ingredients: colloidal silicon dioxide, lactose anhydrous, magnesium stearate, silicified microcrystalline cellulose, and sodium starch glycolate. Tablets are film coated with material containing macrogol/polyethylene glycol, polyvinyl alcohol-partially hydrolyzed, talc, and titanium dioxide.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.