You are using an unsupported browser. Please upgrade your browser to a newer version to get the best experience on DrugBank.
Accession NumberDB00879  (APRD00226)
TypeSmall Molecule
GroupsApproved, Investigational
DescriptionEmtricitabine is a nucleoside reverse transcriptase inhibitor (NRTI) for the treatment of HIV infection in adults. Emtricitabine is an analogue of cytidine. The drug works by inhibiting reverse transcriptase, the enzyme that copies HIV RNA into new viral DNA.
External Identifiers Not Available
Approved Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
EmtrivaCapsule200 mg/1OralExcella Gmb H2003-07-02Not applicableUs
EmtrivaSolution10 mg/mLOralGilead Sciences2005-09-28Not applicableUs
EmtrivaCapsule200 mg/1OralState of Florida DOH Central Pharmacy2009-07-01Not applicableUs
EmtrivaCapsule200 mgOralGilead Sciences2006-03-03Not applicableCanada
EmtrivaCapsule200 mg/1OralPhysicians Total Care, Inc.2003-07-10Not applicableUs
EmtrivaCapsule200 mg/1OralRemedy Repack2008-05-17Not applicableUs
EmtrivaCapsule200 mg/1OralGilead Sciences2003-07-02Not applicableUs
Approved Generic Prescription ProductsNot Available
Approved Over the Counter ProductsNot Available
Unapproved/Other Products Not Available
International Brands
CoviracilNot Available
Brand mixtures
AtriplaLake Erie Medical Dba Quality Care Produts Llc
CompleraPhysicians Total Care, Inc.
DescovyGilead Sciences
GenvoyaGilead Sciences
OdefseyGilead Sciences
StribildState of Florida DOH Central Pharmacy
TruvadaH.J. Harkins Company
SaltsNot Available
CAS number143491-57-0
WeightAverage: 247.247
Monoisotopic: 247.042690096
Chemical FormulaC8H10FN3O3S
NC1=NC(=O)N(C=C1F)[C@@H]1CS[[email protected]](CO)O1
IndicationIndicated, in combination with other antiretroviral agents, for the treatment of HIV-1 infection in adults and for postexposure prophylaxis of HIV infection in health care workers and others exposed occupationally or nonoccupationally via percutaneous injury or mucous membrane or nonintact skin contact with blood, tissues, or other body fluids associated with risk for transmission of the virus.
Structured Indications
Clinical Trials
0Not Yet RecruitingPreventionInfection, Human Immunodeficiency Virus1
1CompletedNot AvailableAcquired Immunodeficiency Syndromes1
1CompletedNot AvailableHIV Disease1
1CompletedHealth Services ResearchHIV Disease1
1CompletedTreatmentInfection, Human Immunodeficiency Virus1
1Not Yet RecruitingTreatmentHealthy1
1RecruitingNot AvailableHIV-DDI1
1RecruitingTreatmentHIV Disease1
1, 2Active Not RecruitingTreatmentAcute HIV Infection1
1, 2CompletedTreatmentInfection, Human Immunodeficiency Virus2
1, 2RecruitingNot AvailablePrEP Adherence Monitoring1
2Active Not RecruitingNot AvailableHIV-1 Infections1
2Active Not RecruitingPreventionInfection, Human Immunodeficiency Virus2
2Active Not RecruitingTreatmentContraception / HIV Disease1
2Active Not RecruitingTreatmentHIV Disease1
2Active Not RecruitingTreatmentInfection, Human Immunodeficiency Virus1
2CompletedPreventionAmphetamine-Related Disorders / HIV Disease / Infection, Human Immunodeficiency Virus1
2CompletedPreventionChronic Hepatitis B Infection1
2CompletedPreventionHIV Seroconversion / Stimulant Abuse1
2CompletedPreventionHIV Seropositivity1
2CompletedPreventionInfection, Human Immunodeficiency Virus1
2CompletedPreventionInfection, Human Immunodeficiency Virus / Pregnancy1
2CompletedTreatmentChronic Hepatitis B Infection1
2CompletedTreatmentHIV Disease / Infection, Human Immunodeficiency Virus1
2CompletedTreatmentHIV-1 Infections5
2CompletedTreatmentHepatitis B Virus (HBV) / Infection, Human Immunodeficiency Virus1
2CompletedTreatmentHuman Immunodeficiency Virus Type 11
2CompletedTreatmentInfection, Human Immunodeficiency Virus9
2CompletedTreatmentInfection, Human Immunodeficiency Virus / Lymphoma, AIDS Related1
2RecruitingTreatmentHuman Immuno Deficiency (HIV) Infection1
2RecruitingTreatmentInfection, Human Immunodeficiency Virus1
2RecruitingTreatmentInfection, Human Immunodeficiency Virus / Tuberculosis1
2TerminatedTreatmentHIV Disease1
2, 3Active Not RecruitingTreatmentHIV Disease1
2, 3CompletedTreatmentInfection, Human Immunodeficiency Virus2
3Active Not RecruitingTreatmentHIV Disease2
3Active Not RecruitingTreatmentHuman Immunodeficiency Virus-type 1 Infection1
3Active Not RecruitingTreatmentInfection, Human Immunodeficiency Virus1
3Active Not RecruitingTreatmentInfection, Human Immunodeficiency Virus I1
3CompletedNot AvailableHIV Disease1
3CompletedTreatmentAcquired Immunodeficiency Syndromes / Infection, Human Immunodeficiency Virus4
3CompletedTreatmentAids / Infection, Human Immunodeficiency Virus1
3CompletedTreatmentHIV Disease / Infection, Human Immunodeficiency Virus2
3CompletedTreatmentHIV-1 Infections2
3CompletedTreatmentInfection, Human Immunodeficiency Virus7
3CompletedTreatmentInfection, Human Immunodeficiency Virus / Tuberculosis1
3RecruitingTreatmentAcute HIV Infection1
3RecruitingTreatmentHIV-1 Infections1
3RecruitingTreatmentInfection, Human Immunodeficiency Virus1
3SuspendedPreventionInfection, Human Immunodeficiency Virus1
3SuspendedTreatmentInfection, Human Immunodeficiency Virus1
3TerminatedTreatmentHIV Disease1
4Active Not RecruitingPreventionAdolescent Behaviors / Gender / HIV Disease1
4Active Not RecruitingPreventionHIV Disease / Human Immunodeficiency Virus (HIV)1
4Active Not RecruitingTreatmentHIV Disease1
4Active Not RecruitingTreatmentInfection, Human Immunodeficiency Virus3
4CompletedNot AvailableHIV Disease / Proteinuria1
4CompletedNot AvailableHealthy1
4CompletedNot AvailablePharmacokinetic Study in Healthy Volunteers1
4CompletedBasic ScienceHepatitis C / Infection, Human Immunodeficiency Virus1
4CompletedPreventionInfection, Human Immunodeficiency Virus3
4CompletedTreatmentAcute HIV Infection / Infection, Human Immunodeficiency Virus1
4CompletedTreatmentCardiovascular Diseases / HIV Disease1
4CompletedTreatmentHIV Disease5
4CompletedTreatmentHIV, Combination Therapy1
4CompletedTreatmentHIV-1 Infections2
4CompletedTreatmentHepatitis B / Infection, Human Immunodeficiency Virus2
4CompletedTreatmentInfection, Human Immunodeficiency Virus11
4Not Yet RecruitingBasic ScienceHIV Disease1
4Not Yet RecruitingPreventionHepatitis B,Chronic / Pregnancy1
4Not Yet RecruitingTreatmentAntiretroviral Therapy Intolerance / Patients Compliance1
4Not Yet RecruitingTreatmentHIV Associated Neurocognitive Disorders (HAND) / Neurocognitive Decline1
4Not Yet RecruitingTreatmentHepatitis B,Chronic2
4Not Yet RecruitingTreatmentHepatitis B,Chronic / Pregnancy1
4RecruitingTreatmentChronic Infection With HIV1
4RecruitingTreatmentHIV Disease1
4TerminatedTreatmentAcquired Immune Deficiency Syndrome (AIDS)1
4TerminatedTreatmentHIV Disease1
4WithdrawnTreatmentAcquired Immune Deficiency Syndrome (AIDS) / Infection, Human Immunodeficiency Virus1
4WithdrawnTreatmentHepatitis B1
Not AvailableActive Not RecruitingNot AvailableHIV Disease1
Not AvailableActive Not RecruitingPreventionHIV Disease / Immune Reconstitution Inflammatory Syndrome / Infection, Human Immunodeficiency Virus1
Not AvailableCompletedNot AvailableHIV-1 Infections1
Not AvailableCompletedPreventionInfection, Human Immunodeficiency Virus2
Not AvailableCompletedTreatmentInfection, Human Immunodeficiency Virus1
Not AvailableCompletedTreatmentPrimary Biliary Cirrhosis (PBC)1
Not AvailableNot Yet RecruitingBasic ScienceHIV Disease1
Not AvailableNot Yet RecruitingPreventionHuman Immunodeficiency Virus (HIV)1
Not AvailableNot Yet RecruitingTreatmentHIV Disease / Infertilities1
Not AvailableRecruitingNot AvailableHIV Disease / Illicit Drug User1
Not AvailableRecruitingPreventionHIV Disease2
Not AvailableRecruitingPreventionHIV/AIDS1
Not AvailableRecruitingTreatmentInfection, Human Immunodeficiency Virus1
Not AvailableWithdrawnNot AvailableHIV Infected1
Not AvailableWithdrawnBasic ScienceInfection, Human Immunodeficiency Virus1
Not AvailableWithdrawnTreatmentInfection, Human Immunodeficiency Virus1
PharmacodynamicsEmtricitabine is a nucleoside reverse transcriptase inhibitor (NRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Emtricitabine helps to block HIV reverse transcriptase, a chemical in your body (enzyme) that is needed for HIV to multiply. Emtricitabine is always used with other anti-HIV medicines to treat people with HIV infection. Emtricitabine may lower the amount of HIV in the blood (viral load). Emtricitabine may also help to increase the number of T cells called CD4 cells. Lowering the amount of HIV in the blood lowers the chance of death or infections that happen when your immune system is weak (opportunistic infections). People taking emtricitabine may still get opportunistic infections or other conditions that happen with HIV infection.
Mechanism of actionEmtricitabine works by inhibiting reverse transcriptase, the enzyme that copies HIV RNA into new viral DNA. Emtricitabine is a synthetic nucleoside analogue of cytidine. It is phosphorylated by cellular enzymes to form emtricitabine 5'-triphosphate, which is responsible for the inhibition of HIV-1 reverse transcriptase. It competes with the natural substrate deoxycytidine 5'-triphosphate and incorporates into nascent viral DNA, resulting in early chain termination. Therefore emtricitabine inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate deoxycytidine 5'-triphosphate and by its incorporation into viral DNA. By inhibiting HIV-1 reverse transcriptase, emtricitabine can help to lower the amount of HIV, or "viral load", in a patient's body and can indirectly increase the number of immune system cells (called T cells or CD4+ T-cells). Both of these changes are associated with healthier immune systems and decreased likelihood of serious illness.
TargetKindPharmacological actionActionsOrganismUniProt ID
Reverse transcriptase/RNaseHProteinyes
Human immunodeficiency virus 1Q72547 details
Related Articles
AbsorptionRapidly absorbed (mean absolute bioavailability of 93% for capsules, and 75% for solution). Food does not effect absorption.
Volume of distributionNot Available
Protein bindingVery low (less than 4%)

Minimally transformed (13%), most appears unchanged in urine (86%). The biotransformation of emtricitabine includes oxidation of the thiol moiety to form the 3′-sulfoxide diastereomers (~ 9% of dose) and conjugation with glucuronic acid to form 2′-O-glucuronide (~ 4% of dose). In vitro studies indicate emtricitabine is not an inhibitor or cytochrome P450 enzymes.

Route of eliminationThe renal clearance of emtricitabine is greater than the estimated creatinine clearance, suggesting elimination by both glomerular filtration and active tubular secretion.
Half life10 hours
  • 302 +/- 94 mL/min [Renal Function Creatinine Clearance>80 ml/min]
  • 168 +/- 10 mL/min [Renal Function Creatinine Clearance 50-80 ml/min]
  • 138 +/- 28 mL/min [Renal Function Creatinine Clearance 30-49 ml/min]
  • 99 +/- 6 mL/min [Renal Function Creatinine Clearance<30 ml/min]
  • 64 +/- 12 mL/min [ESRD patients requiring dialysis]
ToxicitySymptoms of overdose include serious liver problems (hepatotoxicity, with liver enlargement and fat in the liver called steatosis) or a lactic acidosis (buildup of an acid in the blood).
Affected organisms
  • Human Immunodeficiency Virus
PathwayCategorySMPDB ID
Emtricitabine Action PathwayDrug actionSMP00741
SNP Mediated EffectsNot Available
SNP Mediated Adverse Drug ReactionsNot Available
Drug Interactions
DrugInteractionDrug group
GanciclovirThe risk or severity of adverse effects can be increased when Ganciclovir is combined with Emtricitabine.Approved, Investigational
LamivudineThe risk or severity of adverse effects can be increased when Lamivudine is combined with Emtricitabine.Approved, Investigational
RibavirinRibavirin may increase the hepatotoxic activities of Emtricitabine.Approved
ValganciclovirThe risk or severity of adverse effects can be increased when Valganciclovir is combined with Emtricitabine.Approved, Investigational
Food Interactions
  • Take without regard to meals.
Synthesis Reference

General References
  1. Masho SW, Wang CL, Nixon DE: Review of tenofovir-emtricitabine. Ther Clin Risk Manag. 2007 Dec;3(6):1097-104. [PubMed:18516268 ]
  2. Long MC, King JR, Acosta EP: Pharmacologic aspects of new antiretroviral drugs. Curr HIV/AIDS Rep. 2009 Feb;6(1):43-50. [PubMed:19149996 ]
  3. Authors unspecified: Emtricitabine/tenofovir disoproxil fumarate. Drugs R D. 2004;5(3):160-1. [PubMed:15139777 ]
  4. Goicoechea M, Best B: Efavirenz/emtricitabine/tenofovir disoproxil fumarate fixed-dose combination: first-line therapy for all? Expert Opin Pharmacother. 2007 Feb;8(3):371-82. [PubMed:17266471 ]
External Links
ATC CodesJ05AR03J05AR18J05AR19J05AR06J05AR17J05AR09J05AR08J05AF09
AHFS Codes
  • 08:18.08.20
PDB EntriesNot Available
FDA labelDownload (328 KB)
MSDSNot Available
Predicted ADMET features
Human Intestinal Absorption+0.9944
Blood Brain Barrier+0.9742
Caco-2 permeable-0.7053
P-glycoprotein substrateNon-substrate0.7363
P-glycoprotein inhibitor INon-inhibitor0.933
P-glycoprotein inhibitor IINon-inhibitor0.9806
Renal organic cation transporterNon-inhibitor0.8614
CYP450 2C9 substrateNon-substrate0.7945
CYP450 2D6 substrateNon-substrate0.8401
CYP450 3A4 substrateNon-substrate0.625
CYP450 1A2 substrateNon-inhibitor0.7748
CYP450 2C9 inhibitorNon-inhibitor0.7384
CYP450 2D6 inhibitorNon-inhibitor0.8666
CYP450 2C19 inhibitorNon-inhibitor0.7947
CYP450 3A4 inhibitorNon-inhibitor0.6915
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.7653
Ames testAMES toxic0.5304
BiodegradationNot ready biodegradable1.0
Rat acute toxicity2.4133 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9861
hERG inhibition (predictor II)Non-inhibitor0.7827
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397 )
  • Gilead sciences inc
Dosage forms
Tablet, film coatedOral
CapsuleOral200 mg/1
CapsuleOral200 mg
SolutionOral10 mg/mL
Unit descriptionCostUnit
Emtriva 200 mg capsule21.75USD capsule
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Patent NumberPediatric ExtensionApprovedExpires (estimated)
CA2075189 No2004-11-302011-01-31Canada
US5814639 Yes1996-03-292016-03-29Us
US5914331 Yes1998-01-022018-01-02Us
US5922695 Yes1998-01-252018-01-25Us
US5935946 Yes1998-01-252018-01-25Us
US5977089 Yes1998-01-252018-01-25Us
US6043230 Yes1998-01-252018-01-25Us
US6639071 Yes1998-08-142018-08-14Us
US6642245 Yes2001-05-042021-05-04Us
US6703396 Yes2001-09-092021-09-09Us
US6838464 No2001-02-262021-02-26Us
US6939964 Yes1998-07-202018-07-20Us
US7067522 No1999-12-202019-12-20Us
US7125879 No2002-08-092022-08-09Us
US7176220 No2003-11-202023-11-20Us
US7390791 No2002-05-072022-05-07Us
US7402588 No1993-02-012010-02-01Us
US7635704 No2006-10-262026-10-26Us
US7800788 No2002-02-022022-02-02Us
US7803788 No2002-02-022022-02-02Us
US8080551 No2003-04-112023-04-11Us
US8101629 No2002-08-092022-08-09Us
US8148374 No2009-09-032029-09-03Us
US8592397 No2004-01-132024-01-13Us
US8598185 No2008-05-012028-05-01Us
US8633219 No2010-04-242030-04-24Us
US8716264 No2004-01-132024-01-13Us
US8754065 No2012-08-152032-08-15Us
US8841310 No2005-12-092025-12-09Us
US8981103 No2006-10-262026-10-26Us
US9018192 No2006-06-132026-06-13Us
US9296769 No2012-08-152032-08-15Us
Experimental Properties
melting point136-140 °CNot Available
water solubility112 mg/mLNot Available
logP-1.4Not Available
pKa2.65Not Available
Predicted Properties
Water Solubility2.0 mg/mLALOGPS
pKa (Strongest Acidic)14.29ChemAxon
pKa (Strongest Basic)-3.1ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count5ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area88.15 Å2ChemAxon
Rotatable Bond Count2ChemAxon
Refractivity55.37 m3·mol-1ChemAxon
Polarizability21.79 Å3ChemAxon
Number of Rings2ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Mass Spec (NIST)Not Available
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, NegativeNot Available
DescriptionThis compound belongs to the class of organic compounds known as 3'-thia pyrimidine nucleosides. These are nucleoside analogues with a structure that consists of a pyrimidine base, which is N-substituted at the 1-position with a 3'-thia derivative (1,3-oxazolidine) of the ribose moiety that is characteristic of nucleosides.
KingdomOrganic compounds
Super ClassNucleosides, nucleotides, and analogues
ClassNucleoside and nucleotide analogues
Sub Class3'-thia pyrimidine nucleosides
Direct Parent3'-thia pyrimidine nucleosides
Alternative Parents
  • 3'-thia pyrimidine nucleoside
  • Aminopyrimidine
  • Halopyrimidine
  • Pyrimidone
  • Aryl fluoride
  • Aryl halide
  • Hydropyrimidine
  • Pyrimidine
  • Imidolactam
  • Heteroaromatic compound
  • Monothioacetal
  • Oxathiolane
  • Oxacycle
  • Azacycle
  • Organoheterocyclic compound
  • Amine
  • Organooxygen compound
  • Organonitrogen compound
  • Organofluoride
  • Organohalogen compound
  • Alcohol
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Primary alcohol
  • Primary amine
  • Organic nitrogen compound
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors


Human immunodeficiency virus 1
Pharmacological action
General Function:
Rna-dna hybrid ribonuclease activity
Specific Function:
Not Available
Gene Name:
Uniprot ID:
Molecular Weight:
65223.615 Da
  1. Modrzejewski KA, Herman RA: Emtricitabine: a once-daily nucleoside reverse transcriptase inhibitor. Ann Pharmacother. 2004 Jun;38(6):1006-14. Epub 2004 Apr 30. [PubMed:15121999 ]
  2. Bang LM, Scott LJ: Emtricitabine: an antiretroviral agent for HIV infection. Drugs. 2003;63(22):2413-24; discussion 2425-6. [PubMed:14609348 ]
  3. Molina JM, Cox SL: Emtricitabine: a novel nucleoside reverse transcriptase inhibitor. Drugs Today (Barc). 2005 Apr;41(4):241-52. [PubMed:16034488 ]


Pharmacological action
General Function:
Protein homodimerization activity
Specific Function:
Required for the phosphorylation of the deoxyribonucleosides deoxycytidine (dC), deoxyguanosine (dG) and deoxyadenosine (dA). Has broad substrate specificity, and does not display selectivity based on the chirality of the substrate. It is also an essential enzyme for the phosphorylation of numerous nucleoside analogs widely employed as antiviral and chemotherapeutic agents.
Gene Name:
Uniprot ID:
Molecular Weight:
30518.315 Da
  1. Bethell R, De Muys J, Lippens J, Richard A, Hamelin B, Ren C, Collins P: In vitro interactions between apricitabine and other deoxycytidine analogues. Antimicrob Agents Chemother. 2007 Aug;51(8):2948-53. Epub 2007 May 21. [PubMed:17517847 ]
comments powered by Disqus
Drug created on June 13, 2005 07:24 / Updated on January 22, 2017 03:52