Fostamatinib Disodium Hexahydrate Tablets, for Oral Use

Fostamatinib is a tyrosine kinase inhibitor. TAVALISSE is formulated with the disodium hexahydrate salt of fostamatinib, a phosphate prodrug that converts to its pharmacologically active metabolite, R406, in vivo.

The chemical name for fostamatinib disodium hexahydrate is disodium (6-[[5-fluoro-2-(3,4,5trimethoxyanilino) pyrimidin-4-yl]amino]-2,2-dimethyl-3-oxo-pyrido[3,2-b][1,4]oxazin-4-yl)methyl phosphate hexahydrate. The molecular formula is C23H24FN6Na2O9P·6H2O, and the molecular weight is 732.52. The structural formula is:

Fostamatinib disodium is a white to off-white powder that is practically insoluble in pH 1.2 aqueous buffer, slightly soluble in water, and soluble in methanol.

Each TAVALISSE oral tablet contains 100 mg or 150 mg fostamatinib, equivalent to 126.2 mg or 189.3 mg fostamatinib disodium hexahydrate, respectively.

The inactive ingredients in the tablet core are mannitol, sodium bicarbonate, sodium starch glycolate, povidone, and magnesium stearate. The inactive ingredients in the film coating are polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350, talc, iron oxide yellow, and iron oxide red.

Storage And Handling

TAVALISSE 100 mg tablets are round, biconvex, orange, film-coated tablets debossed with “100” on one side and “R” on the reverse side.

TAVALISSE 150 mg tablets are oval, biconvex, orange, film-coated tablets debossed with “150” on one side and “R” on the reverse side.

100 mg tablets: Available in bottle of 60 with 2 desiccant canisters     NDC 71332-001-01

150 mg tablets: Available in bottle of 60 with 2 desiccant canisters     NDC 71332-002-01

Store at room temperature, 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Do not remove desiccants.

Dosage Forms And Strengths

TAVALISSE is available as:

• 100 mg tablet: orange, film-coated, round, biconvex tablets debossed with “100” on one side and “R” on the reverse side.
• 150 mg tablet: orange, film-coated, oval, biconvex tablets debossed with “150” on one side and “R” on the reverse side.

Manufactured by: Patheon Whitby 111 Consumers Drive Whitby, Ontario L1N 525 Canada. Revised: Apr 2018.

There is no specific antidote for overdose with TAVALISSE, and the amount of R406 (the pharmacologically active metabolite of fostamatinib) cleared by dialysis is negligible. In the event of an overdose, monitor patient closely for signs and symptoms of adverse reactions, and treat the reactions with supportive care [see WARNINGS AND PRECAUTIONS].

TAVALISSE™
(TAV-a-leese)
(fostamatinib) Tablets, for oral use

What is the most important information I should know about TAVALISSE?

TAVALISSE can cause important side effects, including:

• High blood pressure (hypertension): New or worsening high blood pressure has happened in people treated with TAVALISSE and can be severe. Your blood pressure should be checked regularly. Your healthcare provider may start you on blood pressure medicine or change current medicines to treat your blood pressure. Increased blood pressure can raise the risk for stroke and heart problems.
• Elevated liver enzyme levels: Increased liver enzymes (which may indicate liver injury) have happened with TAVALISSE, and can be severe. Your healthcare provider should do blood tests monthly to check your enzyme levels. The drug may need to be decreased or stopped if these tests suggest the possibility of liver damage.
• Gastrointestinal (GI) problems: TAVALISSE can cause GI upset, such as diarrhea, nausea, vomiting or pain in your stomach area. Your healthcare provider may recommend changes in your diet, drinking more water, and/or medicine to limit these symptoms.
• Decrease in white blood cell counts: TAVALISSE can decrease your white blood cell count, which may increase your risk for infection, including serious infections. Your healthcare provider should do monthly blood tests to check your white blood cell counts.

What is TAVALISSE?

TAVALISSE is a prescription medicine called a SYK inhibitor. TAVALISSE is used to treat adults with low platelet counts (due to persistent or chronic immune thrombocytopenia [ITP]) when an earlier treatment for ITP has not worked well enough.

What should I tell my healthcare provider before taking TAVALISSE?

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

• Have high blood pressure or take medication to control your blood pressure
• Have liver problems
• Have had your spleen removed (splenectomy)
• Have recently had a blood clot in your legs or lungs
• Have recently had surgery
• Have recently had a serious infection
• Are pregnant or plan to become pregnant. Animal studies indicate a risk for harm to an unborn baby.
• Are breastfeeding or plan to breastfeed. You and your healthcare provider should decide if you will take TAVALISSE or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take, including prescription and over-thecounter medicines, vitamins, and herbal supplements. Taking TAVALISSE with certain other medicines may affect how the other medicines work, how TAVALISSE works, and/or can cause side effects.

Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist when you get a new medicine.

How should I take TAVALISSE?

• Take TAVALISSE exactly as your healthcare provider tells you to take it.
• TAVALISSE may be taken with or without food.
• If you miss a dose of TAVALISSE, wait and take your next dose at its regularly scheduled time. Do not take two doses of TAVALISSE at the same time.
• If you take too much TAVALISSE, you may have a higher risk of serious side effects. Call your healthcare provider right away.
• Your healthcare provider will check your platelet count during your treatment with TAVALISSE and change your dose of TAVALISSE as needed.
• Your healthcare provider will check certain other blood tests (liver enzymes and white blood cells) to monitor the safety of TAVALISSE and change your dose of TAVALISSE as needed.
• Tell your healthcare provider about any bruising or bleeding that happens while you take and after you stop taking TAVALISSE.

What are the possible side effects of TAVALISSE?

• High blood pressure (hypertension)
• Elevated liver enzyme levels
• Gastrointestinal (GI) symptoms (diarrhea, nausea, vomiting or stomach pain)
• Decreased white blood cell counts
• Rash
• Fatigue

Call your healthcare provider for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store TAVALISSE tablets?

• Store TAVALISSE at room temperature, between 68°F and 77°F (20°C to 25°C ().
• Keep TAVALISSE in the original container with the lid tightly closed.
• Do not remove the 2 desiccant packs that help to keep your medicine dry.

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

General information about the safe and effective use of TAVALISSE

Medicines are sometimes prescribed for purposes other than those listed in the Patient Information. Do not use TAVALISSE for a condition for which it was not prescribed. Do not give TAVALISSE to other people, even if they have the same symptoms that you have. It may harm them.

What are the ingredients in TAVALISSE?

Active ingredient: fostamatinib disodium hexahydrate

Inactive ingredients: The tablet core contains mannitol, sodium bicarbonate, sodium starch glycolate, povidone, and magnesium stearate. The coating contains polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350, talc, iron oxide yellow, and iron oxide red.