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Generic Name: doravirine
Dosage Form: Tablets
Date of Approval: August 30, 2018
Company: Merck

Treatment for: HIV-1 Infection

Medically reviewed on September 1, 2018

FDA Approves Pifeltro

See also: Atripla

The U.S. Food and Drug Administration (FDA) has approved Pifeltro (doravirine), a new non-nucleoside reverse transcriptase inhibitor (NNRTI) for the combination treatment of HIV-1 infection in adults.

Patient Information

Read this Patient Information before you start treatment and each time you get a refill. There may be new information. This information does not take the place of talking with your healthcare provider about your medical condition or your treatment.

What is Pifeltro?

Pifeltro is a prescription medicine that is used together with other antiretroviral medicines to treat Human Immunodeficiency Virus-1 (HIV-1) infection in adults who have not taken HIV-1 medicines before.

HIV-1 is the virus that causes AIDS (Acquired Immune Deficiency Syndrome).

It is not known if this medicine is safe and effective in children under 18 years of age.

Who should not take Pifeltro?

Do not take Pifeltro if you take any of the following medicines:

  • carbamazepine
  • oxcarbazepine
  • phenobarbital
  • phenytoin
  • enzalutamide
  • rifampin
  • rifapentine
  • mitotane
  • St. John’s wort

Ask your doctor or pharmacist if you are not sure if your medicine is one that is listed above. If you have taken any of the medicines in the past 4 weeks, talk to your doctor or pharmacist before starting treatment with Pifeltro.

Before taking Pifeltro

Before you start treatment with Pifeltro, tell your doctor about all of your medical conditions, including if you:

  • are pregnant or plan to become pregnant. It is not known if Pifeltro can harm your unborn baby. Tell your healthcare provider if you become pregnant during treatment.
    Pregnancy Registry: There is a pregnancy registry for people who take Pifeltro during pregnancy. The purpose of this registry is to collect information about the health of you and your baby. Talk to your doctor about how you can take part in this registry.
  • are breastfeeding or plan to breastfeed. Do not breastfeed if you take Pifeltro.
    • You should not breastfeed if you have HIV-1 because of the risk of passing HIV-1 to your baby.
    • It is not known if Pifeltro can pass into your breast milk.
    • Talk with your doctor about the best way to feed your baby.

Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

  • Some medicines interact with Pifeltro. Keep a list of your medicines to show your doctor and pharmacist.
  • Tell your doctor if you have taken rifabutin in the past four weeks.
  • You can ask your doctor or pharmacist for a list of medicines that interact with Pifeltro.
  • Do not start taking a new medicine without telling your doctor. Your doctor can tell you if it is safe to take Pifeltro with other medicines.

How do I take Pifeltro?

  • Take Pifeltro every day exactly as your doctor tells you to take it.
  • Take Pifeltro one time each day, at about the same time every day.
  • If you take the medicine rifabutin during treatment with Pifeltro, take Pifeltro two times each day, about 12 hours apart, as prescribed by your doctor. You may not have enough doravirine in your blood if you take rifabutin during treatment with Pifeltro.
  • Take Pifeltro tablets with or without food.
  • Do not change your dose or stop treatment without talking to your doctor. Stay under a doctor’s care when taking Pifeltro.
  • It is important that you do not miss or skip doses.
  • If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the next dose at your regular time. Do not take two doses at the same time.
  • If you have any questions, call your doctor or pharmacist.
  • When your Pifeltro supply starts to run low, get more from your doctor or pharmacy. This is very important because the amount of virus in your blood may increase if the medicine is stopped for even a short time. The virus may develop resistance to Pifeltro and become harder to treat.

Pifeltro side effects

Pifeltro can cause serious side effects, including:

  • Changes in your immune system (Immune Reconstitution Syndrome) can happen when you start taking HIV-1 medicines. Your immune system may get stronger and begin to fight infections that have been hidden in your body for a long time. Tell your doctor right away if you start having any new symptoms after starting your HIV-1 medicine.

The most common side effects include:

  • nausea
  • dizziness
  • headache
  • tiredness
  • diarrhea
  • stomach (abdominal) pain
  • abnormal dreams

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 Pifeltro?

  • Store the tablets at room temperature between 68°F to 77°F (20°C to 25°C).
  • Keep the tablets in the original bottle.
  • Do not take the tablets out of the bottle to store in another container, such as a pill box.
  • Keep the bottle tightly closed to protect the tablets from moisture.
  • The Pifeltro bottle contains a desiccant to help keep your medicine dry (protect it from moisture). Keep the desiccant in the bottle. Do not eat the desiccant.

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

General information about the safe and effective use of Pifeltro.

Medicines are sometimes prescribed for purposes other than those listed in the Patient Information leaflet. 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 pharmacist or doctor for information that is written for healthcare professionals.

What are the ingredients in Pifeltro?

Active ingredient: doravirine.

Inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, hypromellose acetate succinate, lactose monohydrate, magnesium stearate, and microcrystalline cellulose. The tablet film coating contains hypromellose, lactose monohydrate, titanium dioxide and triacetin. The coated tablets are polished with carnauba wax.

Further information

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

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