Pifeltro (doravirine) for HIV: Side Effects, Dosage, & Interactions

Generic drug: doravirine

Brand name: Pifeltro

What is Pifeltro (doravirine), and how does it work?

Pifeltro (doravirine) is a prescription medicine that is used together with other HIV-1 medicines to treat Human Immunodeficiency Virus-1 (HIV-1) infection in adults:

• who have not received HIV-1 medicines in the past, or
• to replace their current HIV-1 medicines for people whose healthcare provider determines that they meet certain requirements.

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

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

What are the side effects of Pifeltro?

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 of Pifeltro include:

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

These are not all the possible side effects of Pifeltro.

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

What is the dosage for Pifeltro?

Recommended Dosage

• The recommended dosage regimen of Pifeltro in adults is one 100 mg
  tablet taken orally once daily with or without food.

Dosage Adjustment With
Rifabutin

• If Pifeltro is co-administered with rifabutin, increase Pifeltro dosage
  to one tablet twice daily (approximately 12 hours apart) for the duration of
  rifabutin co-administration.

What drugs interact with Pifeltro?

Effect Of Other Drugs On Pifeltro

Co-administration of Pifeltro with a CYP3A inducer decreases doravirine plasma concentrations, which may reduce Pifeltro efficacy. Co-administration of Pifeltro and drugs that are inhibitors of CYP3A may result in increased plasma concentrations of doravirine.

Table 6 shows significant drug interactions with Pifeltro.

Table 6: Drug Interactions with Pifeltro*

Concomitant Drug Class: Drug Name
Effect on Concentration
Clinical Comment

Androgen Receptors

enzalutamide
↓doravirine
Co-administration is contraindicated with enzalutamide.
At least a 4-week cessation period is recommended prior to initiation of Pifeltro.

Anticonvulsants

carbamazepine
oxcarbazepine
phenobarbital
phenytoin
↓ doravirine
Co-administration is contraindicated with these anticonvulsants. At least a 4-week cessation period is recommended prior to initiation of Pifeltro.

Antimycobacterials

rifampin†
rifapentine
↓ doravirine
Co-administration is contraindicated with rifampin or rifapentine. At least a 4-week cessation period is recommended prior to initiation of Pifeltro.

rifabutin†
↓ doravirine
Increase Pifeltro dosage to one tablet twice daily when co-administered with rifabutin.

Cytotoxic Agents

mitotane
↓ doravirine
Co-administration is contraindicated with mitotane. At least a 4-week cessation period is recommended prior to initiation of Pifeltro.

HIV Antiviral Agents

efavirenz†
etravirine
nevirapine
↓ doravirine
Use with efavirenz, etravirine, or nevirapine is not recommended.

Herbal Products

St. John’s wort
↓doravirine
Co-administration is contraindicated with St. John’s wort. At least a 4-week cessation period is recommended prior to initiation of Pifeltro.

↑ = increase, ↓ = decrease
*This table is not all inclusive.
†The interaction between Pifeltro and the concomitant drug was evaluated in a clinical study.
All other drug-drug interactions shown are anticipated based on the known metabolic and elimination pathways.

No clinically significant changes in concentration were observed for doravirine when co-administered with the following agents:

• dolutegravir,
• TDF,
• lamivudine,
• elbasvir and grazoprevir,
• ledipasvir and sofosbuvir,
• ritonavir,
• ketoconazole,
• aluminum hydroxide/magnesium hydroxide/simethicone containing antacid,
• pantoprazole, and
• methadone.

Effect Of Pifeltro On Other Drugs

No clinically significant changes in concentration were observed for the following agents when co-administered with doravirine:

• dolutegravir,
• lamivudine,
• TDF,
• elbasvir and grazoprevir,
• ledipasvir and sofosbuvir,
• atorvastatin,
• an oral contraceptive containing ethinyl estradiol and levonorgestrel,
• metformin,
• methadone, and
• midazolam.

What is HIV?
See Answer

Is Pifeltro safe to use while pregnant or breastfeeding?

• No adequate human data are available to establish whether or not
  Pifeltro poses a risk to pregnancy outcomes.
• There is a pregnancy exposure registry that monitors pregnancy outcomes in individuals exposed to
  Pifeltro during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263.
• The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers in the United States not breastfeed their infants to avoid risking potential transmission of HIV-1 infection.
• It is unknown whether doravirine is present in human milk, affects human milk production, or has effects on the breastfed infant.
• Because of the potential for (1) HIV-1 transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants), and (3) serious adverse reactions in a breastfed infant, mothers
  should not breastfeed if they are receiving Pifeltro.