(nelfinavir mesylate)

Prescribing Information
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7 DRUG INTERACTIONS

7 DRUG INTERACTIONS

7.1 Potential for VIRACEPT to Affect Other Drugs

Nelfinavir is an inhibitor of CYP3A. Coadministration of VIRACEPT and drugs primarily metabolized by CYP3A (e.g., dihydropyridine calcium channel blockers, HMG-CoA reductase inhibitors, immunosuppressants, and PDE5 inhibitors) may result in increased plasma concentrations of such drugs that could increase or prolong both its therapeutic and adverse effects (see Tables 3 and 6).

7.2 Potential for Other Drugs to Affect VIRACEPT

Nelfinavir is metabolized by CYP3A and CYP2C19. Coadministration of VIRACEPT and drugs that induce CYP3A or CYP2C19, such as rifampin, may decrease nelfinavir plasma concentrations and reduce its therapeutic effect. Coadministration of VIRACEPT and drugs that inhibit CYP3A or CYP2C19 may increase nelfinavir plasma concentrations.

7.3 Established and Other Potentially Significant Drug Interactions

Table 6 provides the effect on concentrations of VIRACEPT or concomitant drug as a result of coadministration with VIRACEPT. These recommendations are based on either drug interaction studies or predicted interactions due to the expected magnitude of interaction and potential for serious adverse events or loss of efficacy.

Table 6: Established and Other Potentially Significant Drug Interactions: Alteration in Dose or Regimen May Be Recommended Based on Drug Interaction Studies [see Clinical Pharmacology (12.3) (Tables 12 and 13) for magnitude of interaction]

Concomitant Drug Class:
Drug Name		Effect on
Concentration		Clinical Comment
HIV Antiviral Agents: Reverse Transcriptase Inhibitors

Delavirdine

↑ nelfinavir (Cmin)
↓ delavirdine

Concentrations of nelfinavir were increased while concentrations of delavirdine were decreased when the two agents were coadministered. Appropriate doses of the combination, with respect to safety and efficacy, have not been established.

Nevirapine

↓ nelfinavir (Cmin)

Concentrations of nelfinavir were decreased when coadministered with nevirapine. An appropriate dose of nelfinavir with respect to safety and efficacy has not been established.

Didanosine

↔ nelfinavir

There was no change in nelfinavir concentration when coadministered with didanosine. However, it is recommended that didanosine be administered on an empty stomach; therefore, didanosine should be given one hour before or two hours after VIRACEPT (given with food).

HIV Antiviral Agents: Protease Inhibitors

Indinavir

↑ nelfinavir
↑ indinavir

Concentrations of both indinavir and nelfinavir were increased when the two agents were coadministered. Appropriate doses for these combinations, with respect to safety and efficacy, have not been established.

Ritonavir

↑ nelfinavir
↔ ritonavir

Concentrations of nelfinavir were increased when coadministered with ritonavir. An appropriate dose of nelfinavir for this combination, with respect to safety and efficacy, has not been established.

Saquinavir

↑ nelfinavir
↑ saquinavir

Concentrations of both saquinavir and nelfinavir were increased when the two agents were coadministered. Appropriate doses for these combinations, with respect to safety and efficacy, have not been established.

ANTICOAGULANT

Warfarin

Warfarin

Coadministration of warfarin and VIRACEPT may affect concentrations of warfarin. It is recommended that the INR (international normalized ratio) be monitored carefully during treatment with VIRACEPT, especially when commencing therapy.

ANTICONVULSANTS

Carbamazepine Phenobarbital
Phenytoin


↓ nelfinavir

↓ phenytoin

Concentrations of nelfinavir may be decreased. VIRACEPT may not be effective due to decreased nelfinavir plasma concentrations in patients taking these agents concomitantly.
Phenytoin plasma/serum concentrations should be monitored; phenytoin dose may require adjustment to compensate for altered phenytoin concentration.

ANTIDEPRESSANT

Trazodone

↑ trazodone

Concomitant use of trazodone and VIRACEPT may increase plasma concentrations of trazodone. Adverse events of nausea, dizziness, hypotension and syncope have been observed following coadministration of trazodone and ritonavir. If trazodone is used with a CYP3A4 inhibitor such as VIRACEPT, the combination should be used with caution and a lower dose of trazodone should be considered.

ANTIGOUT

Colchicine

↑ colchicines

Patients with renal or hepatic impairment should not be given colchicine with VIRACEPT due to the risk of colchicine toxicity.

Treatment of gout flares –
co- administration of colchicine in patients on VIRACEPT:

0.6 mg (1 tablet) × 1 dose, followed by 0.3 mg (half tablet) 1 hour later. Dose to be repeated no earlier than 3 days.

Prophylaxis of gout-flares –
coadministration of colchicine in patients on VIRACEPT:

If the original colchicine regimen was 0.6 mg twice a day, the regimen should be adjusted to 0.3 mg once a day.
If the original colchicine regimen was 0.6 mg once a day, the regimen should be adjusted to 0.3 mg once every other day.

Treatment of familial Mediterranean fever (FMF)– coadministration of colchicine in patients on VIRACEPT:

Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day).

ANTIMYCOBACTERIAL

Rifabutin

↑ rifabutin
↓ nelfinavir
  (750 mg TID)
↔ nelfinavir
  (1250 mg BID)

It is recommended that the dose of rifabutin be reduced to one-half the usual dose when administered with VIRACEPT; 1250 mg BID is the preferred dose of VIRACEPT when coadministered with rifabutin.

ENDOTHELIN RECEPTOR ANTAGONIST

Bosentan

↑ bosentan

Concentrations of bosentan may be increased when coadministered with VIRACEPT. Coadministration of bosentan in patients on VIRACEPT or coadministration of VIRACEPT in patients on bosentan:
Start at or adjust bosentan to 62.5 mg once daily or every other day based upon individual tolerability.

HMG-CoA REDUCTASE INHIBITORS

Atorvastatin
Rosuvastatin

↑ atorvastatin
↑ rosuvastatin

Titrate atorvastatin dose carefully and use the lowest necessary dose; do not exceed atorvastatin 40 mg/day.

IMMUNOSUPPRESSANTS

Cyclosporine
Tacrolimus
Sirolimus

↑ immuno-suppressants
↑ nelfinavir

Concentrations of these immunosuppressants and nelfinavir may be increased by coadministration of these agents with nelfinavir.

INHALED BETA AGONIST

Salmeterol

↑ salmeterol

Concurrent administration of salmeterol with VIRACEPT is not recommended. The combination may result in increased risk of cardiovascular adverse events associated with salmeterol, including QT prolongation, palpitations and sinus tachycardia.

INHALED/NASAL STEROID

Fluticasone

↑ fluticasone

Concomitant use of fluticasone propionate and VIRACEPT may increase plasma concentrations of fluticasone propionate. Use with caution. Consider alternatives to fluticasone propionate, particularly for long-term use.

MACROLIDE ANTIBIOTIC

Azithromycin

↑ azithromycin

Dose adjustment of azithromycin is not recommended, but close monitoring for known side effects such as liver enzyme abnormalities and hearing impairment is warranted.

NARCOTIC ANALGESIC

Methadone

↓ methadone

Concentrations of methadone were decreased when coadministered with VIRACEPT. Dosage of methadone may need to be increased when coadministered with VIRACEPT.

HORMONAL CONTRACEPTIVES

Ethinyl estradiol
Norethindrone

↓ ethinyl estradiol
↓ norethindrone

Concentrations of ethinyl estradiol and norethindrone were decreased when coadministered with VIRACEPT. Alternative or additional contraceptive measures should be used when oral contraceptives containing ethinyl estradiol or norethindrone and VIRACEPT are coadministered.

PDE5 INHIBITORS

Sildenafil
Vardenafil
Tadalafil

↑ PDE5 Inhibitors

Concomitant use of PDE5 inhibitors and VIRACEPT should be undertaken with caution.

May result in an increase in PDE5 inhibitor-associated adverse events, including hypotension, syncope, visual disturbances, and priapism.

Use of PDE5 inhibitors for pulmonary arterial hypertension (PAH):

• Use of sildenafil (REVATIO) is contraindicated when used for the treatment of pulmonary arterial hypertension (PAH) [see Contraindications (4)].

• The following dose adjustments are recommended for use of tadalafil (ADCIRCA™) with VIRACEPT:

Coadministration of ADCIRCA in patients on VIRACEPT or coadministration of VIRACEPT in patients on ADCIRCA:

Start at or adjust ADCIRCA to 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.

Use of PDE5 inhibitors for erectile dysfunction:

Sildenafil at a single dose not exceeding 25 mg in 48 hours, vardenafil at a single dose not exceeding 2.5 mg in 24 hours, or tadalafil at a single dose not exceeding 10 mg dose in 72 hours, is recommended. Use with increased monitoring for adverse events.

PROTON PUMP INHIBITORS

Omeprazole

↓ nelfinavir

Omeprazole decreases the plasma concentrations of nelfinavir. Concomitant use of proton pump inhibitors and VIRACEPT may lead to a loss of virologic response and development of resistance.

ANTIPSYCHOTICS

Quetiapine

↑ quetiapine

Initiation of VIRACEPT in patients taking quetiapine:
Consider alternative antiretroviral therapy to avoid increases in quetiapine drug exposures. If coadministration is necessary, reduce the quetiapine dose to 1/6 of the current dose and monitor for quetiapine-associated adverse reactions. Refer to the quetiapine prescribing information for recommendations on adverse reaction monitoring.

Initiation of quetiapine in patients taking VIRACEPT:
Refer to the quetiapine prescribing information for initial dosing and titration of quetiapine.

Medication Guide
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MEDICATION GUIDE

PATIENT INFORMATION

VIRACEPT (VI-ra-cept)
(nelfinavir mesylate)
Tablets

VIRACEPT (VI-ra-cept)
(nelfinavir mesylate)
Oral Powder

Important: VIRACEPT can interact with other medicines and cause serious side effects. It is important to know the medicines that should not be taken with VIRACEPT. See the section "Do not take VIRACEPT if you:"

What is VIRACEPT?

VIRACEPT is a prescription HIV-1 medicine used with other HIV-1 medicines to treat human immunodeficiency virus (HIV-1) infection. HIV-1 is the virus that causes Acquired Immune Deficiency Syndrome (AIDS).

It is not known if VIRACEPT is safe and effective in children less than 2 years of age.

Do not take VIRACEPT if you:

•
are taking any of the following medicines. VIRACEPT may cause serious life-threatening side effects or death when used with these medicines:
o
alfuzosin
o
amiodarone
o
cisapride
o
ergot-containing medicines:
▪
dihydroergotamine
▪
ergotamine
▪
methylergonovine
o
lovastatin
o
lurasidone
o
midazolam, when taken by mouth for sedation
o
pimozide
o
quinidine
o
rifampin
o
sildenafil (Revatio®), when used for the treatment of pulmonary arterial hypertension (PAH)
o
simvastatin
o
St. John's wort (Hypericum perforatum)
o
triazolam

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

•
have liver problems
•
have kidney problems
•
have phenylketonuria. VIRACEPT Oral Powder contains aspartame.
•
have high blood sugar (diabetes)
•
have hemophilia
•
are pregnant or plan to become pregnant. VIRACEPT may harm your unborn baby.
o
Tell your healthcare provider right away if you become pregnant during treatment with VIRACEPT.
o
Hormonal forms of birth control, such as injections, vaginal rings or implants, contraceptive patches, and some birth control pills may not work during treatment with VIRACEPT. Talk to your healthcare provider about forms of birth control that may be used during treatment with VIRACEPT.
o
Pregnancy Registry. There is a pregnancy registry for women who take VIRACEPT during pregnancy. The purpose of the registry is to collect information about the health of you and your baby. Talk to your healthcare provider about how you can take part in this registry.
•
are breastfeeding or plan to breastfeed. Do not breastfeed if you take VIRACEPT.
o
You should not breastfeed if you have HIV-1 because of the risk of passing HIV-1 to your baby.
o
VIRACEPT can pass into your breast milk.
o
Talk to your healthcare provider about the best way to feed your baby.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements. Some medicines interact with VIRACEPT. 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 medicines that interact with VIRACEPT.
•
Do not start taking a new medicine without telling your healthcare provider. Your healthcare provider can tell you if it is safe to take VIRACEPT with other medicines.
o
Especially tell your healthcare provider if you take medicines that contain didanosine. Take VIRACEPT with food one hour after or more than two hours before you take didanosine.

How should I take VIRACEPT?

•
You should stay under a healthcare provider's care during treatment with VIRACEPT.
•
Take VIRACEPT every day exactly as prescribed by your healthcare provider.
•
Do not change your dose of VIRACEPT or stop treatment without talking to your healthcare provider first.
•
Take VIRACEPT with a meal.
•
VIRACEPT is usually taken 2 or 3 times each day. Your healthcare provider will tell you how much VIRACEPT to take and when to take it.
•
If your child is taking VIRACEPT, your child's healthcare provider will decide the right dose based on your child's weight.
•
VIRACEPT Tablets are film-coated to help make the tablets easier to swallow.
•
If you or your child are unable to swallow the tablets:
o
You may dissolve the tablets in a small amount of water. Once the tablets are dissolved, the liquid will be cloudy.
o
Mix the cloudy liquid well, and then drink it right away.
o
Rinse the glass with water and drink the water to ensure that you take the full dose of VIRACEPT.
•
If you miss a dose of VIRACEPT, take it as soon as possible. If you skip a dose, do not double the next dose.
•
If you take too much VIRACEPT, call your healthcare provider or go to the nearest hospital emergency room right away.
•
Do not run out of VIRACEPT. Get your VIRACEPT refilled from your healthcare provider or pharmacy before you run out.

How should VIRACEPT Oral Powder be prepared?

•
Your healthcare provider should tell you how much VIRACEPT Oral Powder to use.
•
VIRACEPT Oral Powder comes with a scoop for measuring. Ask your healthcare provider or pharmacist for help measuring the correct amount of VIRACEPT Oral Powder.
•
Do not mix VIRACEPT Oral Powder in the container that it comes in. Measure the correct amount of VIRACEPT Oral Powder into a cup.
•
You may mix VIRACEPT Oral Powder with a small amount of water, milk, formula, soy formula, soy milk, or liquid dietary supplements.
•
You should not mix VIRACEPT Oral Powder with acidic food or juice, such as orange juice, apple juice, or applesauce because the mixture may taste bitter.
•
Your child should drink all of the mixture to be sure that the entire dose of VIRACEPT is taken.
•
If your child does not take the dose right away, store in the refrigerator until you are ready to use it. Do not store a mixed dose of VIRACEPT Oral Powder for more than 6 hours.

What are the possible side effects of VIRACEPT?

VIRACEPT can cause serious side effects, including:

•
Diabetes and high blood sugar (hyperglycemia). Some people who take protease inhibitors including VIRACEPT can get high blood sugar, develop diabetes, or your diabetes can get worse. Some people have had to start taking medicine to treat diabetes or have had to change their diabetes medicine. Tell your healthcare provider if you notice an increase in thirst or urinate often while taking VIRACEPT.
•
Increased bleeding in people with hemophilia. Some people with hemophilia have increased bleeding with protease inhibitors including VIRACEPT.
•
Changes in body fat. These changes can happen in people taking HIV-1 medicines. The changes may include an increased amount of fat in the upper back and neck ("buffalo hump"), breast, and around the middle of your body (trunk). Loss of fat from the legs, arms, and face may also happen. The exact cause and long-term health effects of these conditions are not known.
•
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. Call your healthcare provider right away if you start having new symptoms after starting your HIV-1 medicine.

The most common side effects of VIRACEPT in adults and adolescents (13 years of age and older) include:

•
diarrhea
•
nausea
•
rash
•
gas

The most common side effects of VIRACEPT in children (2 years of age to less than 13 years of age) include:

•
diarrhea
•
low white blood cell count (leukopenia and neutropenia)
•
rash
•
loss of appetite
•
stomach-area (abdominal) pain

These are not all the possible side effects of VIRACEPT.

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 VIRACEPT?

•
Store VIRACEPT Tablets and Oral Powder at room temperature, between 59ºF to 86ºF (15ºC to 30ºC).
•
Store VIRACEPT in the original container.
•
Keep the container closed tightly.

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

General information about the safe and effective use of VIRACEPT.

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use VIRACEPT for a condition for which it was not prescribed. Do not give VIRACEPT 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 VIRACEPT that is written for health professionals.

What are the ingredients in VIRACEPT?

Active ingredient: nelfinavir mesylate

Tablet inactive ingredients: calcium silicate, crospovidone, magnesium stearate, hypromellose, and triacetin. In addition, the 250 mg tablet contains FD&C blue #2 powder and the 625 mg tablet contains colloidal silicon dioxide.

Oral powder inactive ingredients: microcrystalline cellulose, maltodextrin, dibasic potassium phosphate, crospovidone, hypromellose, aspartame, sucrose palmitate, and natural and artificial flavor.

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VIRACEPT is a registered trademark of Agouron Pharmaceuticals, LLC

For more information, call 1-800-438-1985.

Trademarks are the property of their respective owners.

LAB-0346-15.0

This Patient Information has been approved by the U.S. Food and Drug Administration.     Revised: 10/2023

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