Tpoxx

Generic name: tecovirimat
Dosage form: capsules and injection

Medically reviewed by A Ras MD.

What is Tpoxx?

Tpoxx is a prescription medicine used to treat smallpox disease caused by a type of virus called variola virus in adults and children who weigh at least 13 kg.

Tpoxx may not work well in people who have a weakened immune system.

The effectiveness of Tpoxx has been studied only in animals with orthopoxvirus diseases. There have been no human studies in people who have smallpox disease. The safety of Tpoxx was studied in adults. There have been no studies of Tpoxx in children 17 years of age and younger.

Description

TPOXX capsules and TPOXX injection contains tecovirimat, an inhibitor of the orthopoxvirus VP37 envelope wrapping protein.

TPOXX (tecovirimat) capsules, for oral use are immediate release capsules containing tecovirimat monohydrate equivalent to 200 mg of tecovirimat for oral administration. The capsules include the following inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, hydroxypropyl methyl cellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and sodium lauryl sulfate. The capsule shell is composed of gelatin, FD&C blue #1, FD&C red #3, FD&C yellow #6, and titanium dioxide.

TPOXX (tecovirimat) injection, for intravenous use is a sterile, colorless to pale yellow solution free of visible particles that is intended for intravenous use following dilution. Tecovirimat injection is available in a single-dose vial containing 200 mg/20 mL (10 mg/mL) of tecovirimat and 8,000 mg (400 mg/mL) of Hydroxypropyl Betadex, NF (hydroxypropyl β-cyclodextrin) and Water for Injection, USP/NF.

Tecovirimat monohydrate is a white to off-white crystalline solid with the chemical name Benzamide, N-[(3aR,4R,4aR,5aS,6S,6aS)-3,3a,4,4a,5,5a,6,6a-octahydro-1,3-dioxo-4,6 ethenocycloprop[f]isoindol-2(1H)-yl]-4-(trifluoromethyl), rel-(monohydrate). The chemical formula is C19H15F3N2O3·H2O representing a molecular weight of 394.35 g/moL. The molecular structure is as follows:

Tecovirimat monohydrate is practically insoluble in water and across the pH range of 2.0-6.5 (< 0.1 mg/mL).

What should I tell my healthcare provider before taking Tpoxx?

Before taking Tpoxx, tell your healthcare provider about all of your medical conditions, including if you:

have diabetes.
are pregnant or plan to become pregnant. It is not known if Tpoxx can harm your unborn baby. Tell your healthcare provider if you become pregnant during treatment with Tpoxx.
are breastfeeding or plan to breastfeed. It is not known if Tpoxx passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby.

Tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Some medicines interact with Tpoxx. Keep a list of your medicines to show your healthcare provider and pharmacist.

You can ask your healthcare provider or pharmacist for a list of medications that interact with Tpoxx.
Do not start taking a new medicine without telling your healthcare provider. Your healthcare provider can tell you if it is safe to take Tpoxx with other medicines.

How should I take Tpoxx?

Take Tpoxx exactly as your healthcare provider tells you.
For adults and children who weigh at least 40 kg, take 3 capsules of Tpoxx twice a day by mouth for 14 days.
Tpoxx should be taken within 30 minutes after eating a full, fatty meal. Talk to your healthcare provider about examples of foods that you can eat that contain about 25 grams of fat. Always take Tpoxx with food.
See the instructions for use that comes with your Tpoxx for instructions on how to prepare and take a dose of Tpoxx if:
- your child weighs less than 40 kg, OR
- you or your child have trouble swallowing Tpoxx capsules.
Stay under the care of your healthcare provider during treatment with Tpoxx.
Do not change your dose or stop taking Tpoxx without talking to your healthcare provider.
It is important to take Tpoxx for the full 14 day course of treatment. Do not miss or skip a dose of Tpoxx.
If you take too much Tpoxx, call your healthcare provider or go to the nearest hospital emergency room right away.

What are the possible side effects of Tpoxx?

Tpoxx may cause serious side effects, including:

Low blood sugar (hypoglycemia). Low blood sugar can happen when Tpoxx is taken with repaglinide, a medicine used to treat type 2 diabetes. Tell your healthcare provider if you get any of the following symptoms of low blood sugar:
- headache
- drowsiness
- hunger
- feeling jittery or shaky
- dizziness
- confusion
- sweating
- weakness
- fast heartbeat
- irritability

The most common side effects of Tpoxx include:

headache
nausea
stomach pain
vomiting

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

General information about the safe and effective use of Tpoxx

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

How should I store Tpoxx?

Store Tpoxx at room temperature between 68°F to 77°F (20°C to 25°C).
Keep Tpoxx in its original container.

Keep Tpoxx and all other medicines out of the reach of children.

What are the ingredients in Tpoxx?

Active ingredient: tecovirimat

Inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, hydroxypropyl methyl cellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and sodium lauryl sulfate. The capsule shell is made of gelatin, FD&C blue #1, FD&C red #3, FD&C yellow #6, and titanium dioxide.