Global Statistics

All countries
Updated on October 14, 2021 7:22 pm
All countries
Updated on October 14, 2021 7:22 pm
All countries
Updated on October 14, 2021 7:22 pm

Global Statistics

All countries
Updated on October 14, 2021 7:22 pm
All countries
Updated on October 14, 2021 7:22 pm
All countries
Updated on October 14, 2021 7:22 pm

Prezcobix (darunavir and cobicistat) HIV Drug Side Effects & Dosage

Generic drug: darunavir and cobicistat

Brand name: Prezcobix

What is Prezcobix (darunavir and cobicistat), and how does it work?

Prezcobix (darunavir and cobicistat) is a prescription medicine that is used with other HIV-1 medicines to treat HIV-1 infection in adults and in children who weigh at least 88 pounds (40 kg).

What are the side effects of Prezcobix?

Prezcobix may cause serious side effects, including:

  • Diabetes and high blood sugar (hyperglycemia). Some people who take protease inhibitors including
    Prezcobix can get high blood sugar, develop diabetes, or your diabetes can get worse. Tell your healthcare provider if you notice an increase in thirst or urinate often while taking
  • Changes in body fat can happen in people who take HIV-1 medications. 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 HIV1 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 healthcare provider right away if you start having new symptoms after starting your HIV-1 medicine.
  • Increased bleeding for hemophiliacs. Some people with hemophilia have increased bleeding with protease inhibitors including

The most common side effects of darunavir, one of the medicines in
Prezcobix, include:

These are not all of the possible side effects of
Prezcobix. 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 Prezcobix?

Recommended Dosage

Prezcobix is a fixed-dose combination product containing 800 mg of darunavir and 150 mg of cobicistat. In treatment-naïve and treatment-experienced adults and pediatric patients weighing at least 40 kg with no darunavir resistance-associated substitutions, the recommended dosage of
Prezcobix is one tablet taken once daily orally with food. Administer Prezcobix in conjunction with other antiretroviral agents.

Testing Prior To Initiation Of Prezcobix

HIV Genotypic Testing
  • HIV genotypic testing is recommended for antiretroviral treatment-experienced patients.
  • However, when HIV genotypic testing is not feasible,
    Prezcobix can be used in protease inhibitor-naïve patients, but is not recommended in protease inhibitor-experienced patients.
Creatinine Clearance
  • Prior to starting Prezcobix, assess estimated creatinine clearance because
    cobicistat decreases estimated creatinine clearance due to inhibition of tubular
    secretion of creatinine without affecting actual renal glomerular function.
  • When
    co-administering Prezcobix with tenofovir disoproxil fumarate (tenofovir DF)
    assess estimated creatinine clearance, urine glucose, and urine protein at

Not Recommended In Severe Renal Impairment

  • Prezcobix
    co-administered with tenofovir DF is not recommended in patients who have an
    estimated creatinine clearance below 70 mL per minute.

Not Recommended In Severe Hepatic Impairment

  • Prezcobix is not recommended for use in patients with severe hepatic impairment.

Not Recommended During Pregnancy

  • Prezcobix is not recommended during pregnancy because of substantially lower
    exposures of darunavir and cobicistat during the second and third trimesters.
  • Prezcobix should not be initiated in pregnant individuals. An alternative regimen is recommended for those who become pregnant during therapy with

What drugs interact with Prezcobix?

Potential For Prezcobix To Affect Other Drugs

  • Darunavir co-administered with cobicistat is an inhibitor of CYP3A and CYP2D6. Cobicistat inhibits the following transporters:
    • P-glycoprotein (P-gp),
    • BCRP, MATE1, OATP1B1 and
    • OATP1B3.
  • Therefore, co-administration of Prezcobix with drugs that are primarily metabolized by CYP3A and/or CYP2D6 or are substrates of P-gp, BCRP, MATE1, OATP1B1 or OATP1B3 may result in increased plasma concentrations of such drugs, which could increase or prolong their therapeutic effect and can be associated with adverse events.
  • Co-administration of Prezcobix with drugs that have active metabolite(s) formed by CYP3A may result in reduced plasma concentrations of these active metabolite(s), potentially leading to loss of their therapeutic effect (see Table 1).

Potential For Other Drugs To Affect Prezcobix

  • Darunavir is metabolized by CYP3A. Cobicistat is metabolized by CYP3A, and to a minor extent, by CYP2D6.
  • Co-administration of Prezcobix and drugs that induce CYP3A activity are expected to increase the clearance of darunavir and cobicistat, resulting in lowered plasma concentrations of darunavir and cobicistat which may lead to loss of therapeutic effect and development of resistance.
  • Co-administration of Prezcobix and other drugs that inhibit CYP3A may result in increased plasma concentrations of darunavir and cobicistat (see Table 1).

Established And Other Potentially Significant Drug Interactions

  • Table 1 provides dosing recommendations for expected clinically relevant interactions with
    Prezcobix (this table is not all inclusive). These recommendations are based on either drug interaction trials or predicted interactions due to the expected magnitude of interaction and potential for serious adverse events or loss of therapeutic effect.
  • The table includes potentially significant interactions but is not all inclusive.
    See prescribing information for the list of contraindicated drugs.

Table 1: Established and Other Potentially Significant* Drug Interactions: Alterations in Dose or Regimen May Be Recommended

Concomitant Drug Class:
Drug NameEffect on Concentration of Darunavir, Cobicistat, or Concomitant DrugClinical CommentHIV-1 antiviral agents: Nucleoside Reverse Transcriptase Inhibitors (NRTIs)Didanosine↔ darunavirDidanosine should be administered one hour before or two hours after
Prezcobix (administered with food).↔ cobicistat↔ didanosineHIV-1 antiviral agents: Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)Efavirenz↓ cobicistatCo-administration with efavirenz is not recommended because it may result in loss oftherapeutic effect and development of resistance to darunavir.↓ darunavirEtravirine↓ cobicistat darunavir: effect unknownCo-administration with etravirine is not recommended because it may result in loss oftherapeutic effect and development of resistance todarunavir.Nevirapine↓ cobicistat darunavir: effect unknownCo-administration with nevirapine is notrecommended because it may result in loss oftherapeutic effect and development of resistance to darunavir.HIV-1 antiviral agents: CCR5 co-receptor antagonistsMaraviroc↑ maravirocMaraviroc is a substrate of CYP3A. When co-administered with
Prezcobix, patients shouldreceive maraviroc 150 mg twice daily.Other agentsAlpha 1-adrenoreceptor antagonist:↑ alfuzosinCo-administration is contraindicated due to potential for serious and/or life-threateningreactions such as hypotension.AlfuzosinAntibacterials:clarithromycin, erythromycin, telithromycin↑ darunavirConsider alternative antibiotics with concomitant use of
Prezcobix.↑ darunavir↑ antibacterialAnticancer agents:↑ anticancer agentA decrease in the dosage or an adjustment of the dosing interval of dasatinib or nilotinib may benecessary when co-administered with
Prezcobix. Consult the dasatinib and nilotinib prescribing information for dosing instructions.dasatinib, nilotinibvinblastine, vincristineFor vincristine and vinblastine, consider temporarily withholding the cobicistat-containing antiretroviral regimen in patients who developsignificant hematologic or gastrointestinal sideeffects when
Prezcobix is administered concurrently with vincristine or vinblastine. If the antiretroviral regimen must be withheld for aprolonged period, consider initiating a revised regimen that does not include a CYP3A or P-gpinhibitor.Anticoagulants:↑ apixabanDue to potentially increased bleeding risk, dosingrecommendations for co-administration of apixabanwith
Prezcobix depends on the apixaban dose. Refer to apixaban dosing instructions forco-administration with strong CYP3A and P-gpinhibitors in apixaban prescribing information.Direct Oral Anticoagulants (DOACs)
apixabanrivaroxaban↑ rivaroxabanCo-administration of rivaroxaban with
Prezcobix is not recommended because it may lead to an increased bleeding risk.betrixaban↔ betrixabanNo dose adjustment is needed when betrixaban,dabigatran, or edoxaban is co-administered withPrezcobix.dabigatran↔ dabigatranedoxaban↔ edoxabanOther Anticoagulants:warfarinwarfarin: effect unknownMonitor the international normalized ratio (INR) when co-administering with warfarin.Anticonvulsants:↓ darunavirCo-administration is contraindicated due to potential for reduced plasma concentrations of darunavir, which may result in loss of therapeuticeffect and development of resistance.carbamazepine, phenobarbital, phenytoin↓ cobicistatAnticonvulsants with CYP3A induction effects that are NOT contraindicated:↓ cobicistat darunavir: effect unknownConsider alternative anticonvulsant or antiretroviral therapy to avoid potential changes in exposures. If co-administration is necessary, monitor for lack orloss of virologic response.e.g. eslicarbazepine, oxcarbazepineAnticonvulsants that are metabolized by CYP3A:↑ clonazepamClinical monitoring of anticonvulsants is recommended.e.g. clonazepamAntidepressants:SSRIs: effects unknownWhen co-administering with SSRIs, TCAs, ortrazodone, careful dose titration of the antidepressant to the desired effect, including using the lowest feasible initial or maintenance dose, and monitoring for antidepressant response arerecommended.Selective Serotonin ReuptakeInhibitors (SSRIs):e.g. paroxetine, sertralineTricyclic Antidepressants (TCAs):↑ TCAse.g. amitriptyline, desipramine, imipramine, nortriptylineOther antidepressants:↑ trazodonetrazodoneAntifungals:↑ darunavirMonitor for increased darunavir or cobicistat and/or antifungal adverse reactions.itraconazole, isavuconazole, ketoconazole, posaconazole↑ cobicistat↑ itraconazoleSpecific dosing recommendations are not available for co-administration with these antifungals.Monitor for increased itraconazole or ketoconazole adverse reactions.↑ ketoconazole↑ isavuconazolevoriconazole↔ posaconazole voriconazole: effects unknownCo-administration with voriconazole is not recommended unless benefit/risk assessmentjustifies the use of voriconazole.Anti-gout:
colchicine↑ colchicineCo-administration is contraindicated in patients with renal and/or hepatic impairment due topotential for serious and/or life-threatening reactions.For patients without renal or hepatic impairment:

  • Treatment of gout flares – co-administration of colchicine: 0.6 mg (1 tablet) x 1 dose, followedby 0.3 mg (half tablet) 1 hour later. Treatment course to be repeated no earlier than 3 days.
  • Prophylaxis of gout flares – co-administrationof colchicine: If the original regimen was 0.6 mg twice a day, the regimen should beadjusted to 0.3mg once a day. If the original regimen was 0.6 mg once a day, the regimenshould be adjusted to 0.3mg once every otherday.
  • Treatment of familial Mediterranean fever – co-administration of colchicine: Maximum daily dose of 0.6 mg (may be given as 0.3mg twice a day).

Antimalarial:artemether: effect unknownMonitor for a potential decrease of antimalarial efficacy or potential QT prolongation.artemether/lumefantrinelumefantrine: effect unknownAntimycobacterials:↓ darunavirCo-administration is contraindicated due to potential for loss of therapeutic effect anddevelopment of resistance.rifampin↓ cobicistatrifabutin↑ rifabutin cobicistat: effects unknown darunavir: effects unknownWhen used in combination with
Prezcobix, the recommended dose of rifabutin is 150 mg everyother day. Monitor for rifabutin-associated adverse reactions including neutropenia and uveitis.rifapentine↓ darunavirCo-administration with rifapentine is not recommended.Antipsychotics:
lurasidone↑ lurasidoneCo-administration is contraindicated due to potential for serious and/or life-threatening reactions.pimozide↑ pimozideCo-administration is contraindicated due to potential for serious and/or life-threatening reactions such as cardiac arrhythmias.e.g. perphenazine, risperidone, thioridazine↑ antipsychoticA decrease in the dose of antipsychotics that aremetabolized by CYP3A or CYP2D6 may be needed when co-administered with
Prezcobix.quetiapine↑ quetiapineInitiation of
Prezcobix in patients taking quetiapine:
Consider alternative antiretroviral therapy to avoid increases in quetiapine exposure. Ifco-administration is necessary, reduce thequetiapine dose to 1/6 of the current dose and monitor for quetiapine-associated adverse reactions. Refer to the quetiapine prescribinginformation for recommendations on adverse reaction monitoring.Initiation of quetiapine in patients taking
Refer to the quetiapine prescribinginformation for initial dosing and titration of quetiapine.β-Blockers:↑ beta-blockersClinical monitoring is recommended for co-administration with beta-blockers that are metabolized by CYP2D6.e.g. carvedilol, metoprolol,timololCalcium channel blockers:↑ calcium channel blockersClinical monitoring is recommended for co-administration with calcium channel blockers metabolized by CYP3A.e.g. amlodipine, diltiazem, felodipine, nifedipine, verapamilCardiac Disorders:ranolazine, ivabradine↑ ranolazineCo-administration is contraindicated due to potential for serious and/or life-threatening reactions.↑ ivabradinedronedarone↑ dronedaroneCo-administration is contraindicated due to potential for serious and/or life-threateningreactions such as cardiac arrhythmias.Other antiarrhythmicse.g. amiodarone, disopyramide, flecainide, lidocaine (systemic), mexiletine, propafenone, quinidine digoxin↑ antiarrhythmicsClinical monitoring is recommended upon co-administration with antiarrhythmics.↑ digoxinWhen co-administering with digoxin, titrate thedigoxin dose and monitor digoxin concentrations.Systemic/Inhaled/ Nasal/ Ophthalmic Corticosteroids: e.g.↓ darunavirCo-administration with systemic dexamethasone or other systemic corticosteroids that induce CYP3Amay result in loss of therapeutic effect anddevelopment of resistance to
Prezcobix. Consider alternative corticosteroids.↓ cobicistat↑ corticosteroidsbetamethasoneCo-administration with corticosteroids of which exposures are significantly increased by strongCYP3A inhibitors can increase the risk for Cushing’s syndrome and adrenal suppression.Alternative corticosteroids includingbeclomethasone, prednisone and prednisolone (for which PK and/or PD are less affected by strongCYP3A inhibitors relative to other steroids) shouldbe considered, particularly for long term use.budesonideciclesonidedexamethasonefluticasonemethylprednisolonemometasonetriamcinoloneEndothelin receptor antagonists:↓ darunavirInitiation of bosentan in patients taking
In patients who have been receiving Prezcobix for at least 10 days, start bosentan at 62.5 mg once daily or every other day based uponindividual tolerability.↓ cobicistat↑ bosentanInitiation of
Prezcobix in patients on bosentan:
Discontinue use of bosentan at least 36 hours priorto initiation of
Prezcobix. After at least 10 days following the initiation of Prezcobix, resumebosentan at 62.5 mg once daily or every other day based upon individual tolerability.Switching from darunavir co-administered with ritonavir to
Prezcobix in patients on bosentan:
Maintain bosentan dose.Ergot derivatives:↑ ergot derivativesCo-administration is contraindicated due to potential for serious and/or life-threatening reactions such as acute ergot toxicity characterized by peripheral vasospasm and ischemia of the extremities and other tissues.e.g. dihydroergotamine, ergotamine, methylergonovineGI motility agent:↑ cisaprideCo-administration is contraindicated due to potential for serious and/or life-threateningreactions such as cardiac arrhythmias.cisaprideHepatitis C virus (HCV):↑ elbasvir/grazoprevirCo-administration is contraindicated due to potential for the increased risk of alanine transaminase (ALT) elevations.Direct-Acting Antivirals:elbasvir/grazoprevirglecaprevir/pibrentasvir↑ glecaprevirCo-administration of
Prezcobix with glecaprevir/pibrentasvir is not recommended.↑ pibrentasvirHerbal product:↓ darunavirCo-administration is contraindicated due to potential for reduced plasma concentrations of darunavir, which may result in loss of therapeuticeffect and development of resistance.St. John’s wort (Hypericum perforatum)↓ cobicistatHormonal contraceptives:Additional or alternative (non-hormonal) forms of contraception should be considered when estrogen-containing contraceptives are co-administered with
Prezcobix [see Use In Specific Populations].drospirenone/ ethinylestradiol↑ drospirenone↓ ethinylestradiolFor co-administration with drospirenone, clinical monitoring is recommended due to the potential forhyperkalemia.Other progestin/ estrogen contraceptivesprogestin: effectsunknown estrogen: effects unknownNo data are available to make recommendations on co-administration with other hormonal contraceptives.Immunosuppressants:↑ immunosuppressantsThese immunosuppressant agents are metabolizedby CYP3A. Therapeutic drug monitoring is recommended with concomitant usecyclosporine, sirolimus, tacrolimusImmunosuppressant /neoplastic:↑ immunosuppressantsCo-administration of everolimus and
Prezcobix is not recommended.everolimusirinotecanDiscontinue
Prezcobix at least 1 week prior tostarting irinotecan therapy. Do not administer
Prezcobix with irinotecan unless there are no therapeutic alternatives.Inhaled beta agonist:↑ salmeterolCo-administration with salmeterol is not recommended and may result in increased risk ofcardiovascular adverse events associated with salmeterol, including QT prolongation, palpitations, and sinus tachycardia.salmeterolLipid Modifying AgentsHMG-CoA reductase inhibitors:↑ lovastatinCo-administration is contraindicated due to potential for serious reactions such as myopathy including rhabdomyolysis.lovastatin, simvastatin↑ simvastatinatorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin↑ atorvastatinFor atorvastatin, fluvastatin, pitavastatin,pravastatin, and rosuvastatin, start with the lowest recommended dose and titrate while monitoring forsafety (e.g. myopathy).↑ fluvastatin↑ pravastatin↑ rosuvastatin pitavastatin: effect unknownDosage recommendations with atorvastatin orrosuvastatin are as follows:

  • atorvastatin dosage should not exceed 20 mg/day
  • rosuvastatin dosage should not exceed 20 mg/day

Other lipid modifying agents:↑ lomitapideCo-administration is contraindicated due to potential for markedly increased transaminases associated with increased plasma concentrations oflomitapide.lomitapideNarcotic analgesics metabolized by CYP3A:↑ fentanylCareful monitoring of therapeutic effects and adverse reactions associated with CYP3Ae metabolized narcotic analgesics (includingpotentially fatal respiratory depression) is recommended with co-administration.e.g. fentanyl, oxycodone↑ oxycodonetramadol↑ tramadolA dose decrease may be needed for tramadol with concomitant use.Narcotic analgesic for treatment of opioiddependence:buprenorphine or buprenorphine/ naloxone:effects unknown methadone: effects unknownInitiation of buprenorphine, buprenorphine/naloxone or methadone in patientstaking
Carefully titrate the dose of buprenorphine, buprenorphine/naloxone ormethadone to the desired effect; use the lowest feasible initial or maintenance dose.buprenorphine, buprenorphine/ naloxone, methadoneInitiation of
Prezcobix in patients takingbuprenorphine, buprenorphine/naloxone or methadone:
A dose adjustment for buprenorphine,buprenorphine/naloxone or methadone may be needed. Monitor clinical signs and symptoms.Opioid Antagonist
naloxegol↑ naloxegolCo-administration of
Prezcobix and naloxegolis contraindicated due to potential for precipitating opioid withdrawal symptoms.Phosphodiesterase PDE-5 inhibitors:↑ PDE-5 inhibitorsCo-administration with avanafil is not recommended because a safe and effective avanafil dosage regimen has not been established.e.g. avanafil, sildenafil, tadalafil, vardenafilCo-administration with PDE-5 inhibitors may result in an increase in PDE-5 inhibitor-associated adverse reactions including hypotension, syncope, visualdisturbances and priapism.Use of PDE-5 inhibitors for pulmonary arterialhypertension (PAH):
Co-administration with sildenafil used for PAH is contraindicated due to potential for sildenafil associated adverse reactions (which include visualdisturbances, hypotension, prolonged erection, andsyncope).The following dose adjustments are recommendedfor use of tadalafil with

  • Initiation of tadalafil in patients taking
    In patients receivingPrezcobix for at least one week, start tadalafil at 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.
  • Initiation of
    Prezcobix in patients taking tadalafil:
    Avoid use of tadalafil during the initiation of
    Prezcobix. Stop tadalafil at least24 hours prior to starting Prezcobix. After at least one week following the initiation ofPrezcobix, resume tadalafil at 20 mg oncedaily. Increase to 40 mg once daily based upon individual tolerability.
  • Patients switching from darunavir co-administered withritonavir to
    Maintain tadalafil dose.

Use of PDE-5 inhibitors for erectile dysfunction: Sildenafil at a single dose not exceeding 25 mg in48 hours, vardenafil at a single dose not exceeding 2.5 mg dose in 72 hours, or tadalafil at a single dose not exceeding 10 mg dose in 72 hours can be used with increased monitoring for PDE-5inhibitor-associated adverse reactions.Platelet aggregation inhibitor:ticagrelor↑ ticagrelorCo-administration of
Prezcobix and ticagrelor isnot recommended.clopidogrel↓ clopidogrel active metaboliteCo-administration of
Prezcobix with clopidogrel is not recommended due to the potential reduction of the antiplatelet activity of clopidogrel.prasugrel1↔ prasugrel activemetaboliteNo dose adjustment is needed when prasugrel isco-administered with
Prezcobix.Sedatives/hypnotics:↑ midazolamorally administeredmidazolam, triazolam↑ triazolamCo-administration is contraindicated due to potential for serious and/or life-threateningreactions such as prolonged or increased sedation orrespiratory depression. Triazolam and orally administered midazolam are extensivelymetabolized by CYP3A. Co-administration oftriazolam or orally administered midazolam with
Prezcobix may cause large increases in theconcentrations of these benzodiazepines. With concomitant use, titration is recommended with sedatives/hypnotics metabolized by CYP3Aand a lower dose of the sedatives/hypnotics should be considered with monitoring for increased andprolonged effects or adverse reactions. Co-administration of parenteral midazolam should be done in a setting that ensures close clinicalmonitoring and appropriate medical management in case of respiratory depression and/or prolongedsedation. Dose reduction for parenteral midazolamshould be considered, especially if more than a single dose of midazolam is administered.metabolized by CYP3A:
e.g. buspirone, diazepam, estazolam, zolpidem↑ sedatives/hypnoticsparenterally administered midazolamUrinary antispasmodicsfesoterodine↑ fesoterodineWhen fesoterodine is co-administered with
Prezcobix, do not exceed a fesoterodine dose of 4 mg once daily.solifenacin↑ solifenacinWhen solifenacin is co-administered with
Prezcobix, do not exceed a solifenacin dose of 5 mg once daily.* this table is not all inclusive

Drugs Without Clinically Significant Interactions With Prezcobix

Latest HIV News

Trending on MedicineNet

Is Prezcobix safe to use while pregnant or breastfeeding?

  • There are insufficient data with Prezcobix in pregnant individuals from the APR to inform a drug-associated risk of pregnancy outcomes.
  • The Centers for Disease Control and Prevention recommend that HIV infected mothers in the United States not breastfeed their infants to avoid risking postnatal transmission of HIV.
  • There are no data on the presence of darunavir or cobicistat in human milk, the effects on the breastfed infant, or the effects on milk production.
  • Darunavir and cobicistat are present in the milk of lactating rats (see Data). Because of the potential for (1) HIV transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants), and (3) serious adverse reactions in breastfed infants, instruct mothers not to breastfeed if they are receiving

Hot Topics

Related Articles