Dolutegravir sodium and lamivudine (dolutegravir/lamivudine) is a fixed-combination antiretroviral agent containing dolutegravir (a human immunodeficiency virus integrase strand transfer inhibitor [INSTI]) and lamivudine (an HIV nucleoside reverse transcriptase inhibitor [NRTI]).1
The fixed combination of dolutegravir sodium and lamivudine (dolutegravir/lamivudine) is used as a complete regimen for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in antiretroviral-naive (have not previously received antiretroviral therapy) adults or to replace the current antiretroviral regimen in those who are virologically suppressed (HIV-1 RNA <50 copies/mL) on a stable antiretroviral regimen with no history of treatment failure and no known substitutions associated with resistance to dolutegravir or lamivudine.1,2,12,14,15
Dolutegravir and lamivudine are available as a fixed-combination preparation (dolutegravir/lamivudine), and as separate single-entity products.1,236 Refer to the full prescribing information for the single-entity products for information on specific uses.219,236
Efficacy of dolutegravir/lamivudine for the treatment of HIV-1 infection in antiretroviral-naive adults is supported by data from 2 identically designed, randomized, double-blind, phase 3 noninferiority trials (GEMINI-1; NCT02831673 and GEMINI-2; NCT02831764).1,2 Pooled 48-week data from these studies indicated that a 2-drug regimen of dolutegravir and lamivudine is noninferior to a 3-drug regimen of dolutegravir, emtricitabine, and tenofovir disoproxil fumarate (TDF) in antiretroviral-naive adults.1,2 Pooled 96-week data from GEMINI-1 and GEMINI-2 confirmed these results and indicated long-term noninferiority of the 2-drug regimen of dolutegravir and lamivudine compared with the 3-drug regimen.3
GEMINI-1 and GEMINI-2 included a total of 1433 adults with HIV-1 infection who had received no prior antiretroviral treatment and had plasma HIV-1 RNA levels of 1000-500,000 copies/mL, no evidence of hepatitis B virus (HBV) infection, and no major HIV mutations associated with resistance to HIV NRTIs, HIV nonnucleoside reverse transcriptase inhibitors (NNRTIs), or HIV protease inhibitors (PIs) at initial screening.1,2 Patients were randomized 1:1 to receive a 2-drug regimen of single-entity dolutegravir and single-entity lamivudine (dolutegravir 50 mg and lamivudine 300 mg) once daily or a 3-drug regimen of single-entity dolutegravir and the fixed combination of emtricitabine and TDF (dolutegravir 50 mg, emtricitabine 200 mg, and TDF 300 mg) once daily.1,2 The primary efficacy end point in both trials was the proportion of patients in the intention-to-treat (ITT) population with plasma HIV-1 RNA levels <50 copies/mL at 48 weeks.1,2 Pooled analysis of the ITT populations indicated that study participants had a median age of 33 years, 15% were female, 69% were white, 9% were CDC stage 3 (acquired immunodeficiency syndrome [AIDS]), 20% had baseline plasma HIV-1 RNA levels >100,000 copies/mL, and the median CD4+ T-cell count was 432 cells/mm3 (8% had CD4+ T-cell counts of ≤200 cells/mm3); patient characteristics were similar in both studies.1,2
At 48 weeks, pooled data for the ITT populations in GEMINI-1 and GEMINI-2 indicated that 91% of patients receiving the 2-drug regimen and 93% of those receiving the 3-drug regimen had plasma HIV-1 RNA levels <50 copies/mL.1,2 When results were stratified by baseline CD4+ T-cell count, the response rate (i.e., plasma HIV-1 RNA levels <50 copies/mL) was lower in patients with baseline CD4+ T-cell counts of ≤200 cells/mm3 (pooled response rate was 79% in those receiving the 2-drug regimen and 93% in those receiving the 3-drug regimen) compared with the response rate in patients with higher baseline CD4+ T-cell counts (pooled response rate was 93% in both treatment groups).1,2
Pooled data from another prespecified secondary analysis of GEMINI-1 and GEMINI-2 performed at 144 weeks indicated that the 2-drug regimen of dolutegravir and lamivudine remained noninferior to the 3-drug regimen of dolutegravir and the fixed combination of emtricitabine and TDF.1,3 At 144 weeks, 82% of patients receiving the 2-drug regimen and 84% of patients receiving the 3-drug regimen still had plasma HIV-1 RNA levels <50 copies/mL.1,3 The adjusted mean change in CD4+ T-cell count from baseline at week 144 was 302 cells/mm3 in those receiving dolutegravir and lamivudine and 300 cells/mm3 in those receiving dolutegravir and the fixed combination of emtricitabine and TDF.1 At week 144, treatment-emergent substitutions associated with resistance to dolutegravir or NRTIs were not detected in any patients in either treatment arm.1
Antiretroviral-experienced Adults
Efficacy of dolutegravir/lamivudine for the treatment of HIV-1 infection in antiretroviral-experienced adults is primarily supported by data from a randomized, open-label, phase 3 trial (TANGO; NCT03446573).1,12 In the TANGO trial, 741 previously treated HIV-infected adults who were virologically suppressed for more than 6 months on a 3-drug antiretroviral regimen that included tenofovir alafenamide (TAF; i.e., TAF and emtricitabine in conjunction with an HIV INSTI, NNRTI, or boosted PI) and had no history of virologic failure and no evidence of resistance to INSTIs or NRTIs were randomized 1:1 to switch to a 2-drug regimen of dolutegravir and lamivudine (fixed-combination tablet containing dolutegravir 50 mg/lamivudine 300 mg once daily) or continue their current TAF-based regimen.1,12 Patients with HBV coinfection were excluded.12 The primary endpoint was the proportion of patients with plasma HIV-1 RNA ≥50 copies/mL (virologic nonresponse) at week 48.1
At baseline, the median age was 39 years; 8% of patients were female, 21% were non-white, 5% were CDC stage 3 (AIDS), and 98% had baseline CD4+ T-cell counts ≥200 cells/mm3.1 Most patients were on an INSTI-based, TAF-based regimen prior to study enrollment, and the median length of antiretroviral treatment prior to study enrollment was 2.8 years in the dolutegravir/lamivudine group and 2.9 years in the group continuing their TAF-based regimen.1 The 48-week data indicated that a switch to a 2-drug regimen of dolutegravir/lamivudine in virologically suppressed patients was noninferior to continued treatment with a 3-drug TAF-based regimen.1,12 The rate of virologic nonresponse was <1% in both treatment arms at week 48.1 At week 144, switching to dolutegravir/lamivudine remained noninferior to continuation of a TAF-based regimen; the proportion of patients with virologic nonresponse was 0.3% in the dolutegravir/lamivudine group and 1.3% in the group of patients continuing a TAF-based regimen.1,14 Treatment outcomes were similar across subgroups by age, sex, race, baseline CD4+ T-cell count, baseline third-agent class (PI, INSTI, or NNRTI), CDC HIV disease stage, and countries.1 The median change from baseline in CD4+ T-cell count at week 144 was 36 cells/mm3 in the dolutegravir/lamivudine group and 35 cells/mm3 in the group of patients continuing a TAF-based regimen.1
An additional phase 3, randomized, open-label, noninferiority trial (SALSA; NCT04021290) examined the efficacy of switching to dolutegravir/lamivudine compared with continuing various 3- or 4-drug antiretroviral regimens in 493 virologically suppressed adults with HIV-1.15 Patients were eligible for enrollment if they had an undetectable viral load for ≥6 months prior to screening and were stable on their first or second antiretroviral regimen for ≥3 months prior to screening.15 Any prior switch in therapy must not have occurred due to suspected or established treatment failure.15 Acceptable stable antiretroviral regimens were those that included 2 NRTIs plus an INSTI, NNRTI, or PI.15 The primary endpoint was the proportion of patients with plasma HIV-1 RNA ≥50 copies/mL at week 48.15 At baseline, the median age was 45 years; 39% of patients were female, 19% were African American, and 14% were Asian.15 At 48 weeks, switching to dolutegravir/lamivudine was found to be noninferior to continuing the current antiretroviral regimen; the proportion of patients with HIV-1 RNA ≥50 copies/mL was 0.4% in the dolutegravir/lamivudine group and 1.2% in the group of patients continuing their baseline regimen.15
Therapeutic options for the treatment and prevention of HIV infection and recommendations concerning the use of antiretrovirals are continuously evolving.200,201,202 Antiretroviral therapy is recommended for all individuals with HIV regardless of CD4 counts, and should be initiated as soon as possible after diagnosis of HIV and continued indefinitely.200,201,202 The primary goals of antiretroviral therapy are to achieve and maintain durable suppression of HIV viral load (as measured by plasma HIV-1 RNA levels) to a level below which drug-resistance mutations cannot emerge (i.e., below detectable limits), restore and preserve immunologic function, reduce HIV-related morbidity and mortality, improve quality of life, and prevent transmission of HIV.200,202 While the most appropriate antiretroviral regimen cannot be defined for each clinical scenario, the US Department of Health and Human Services (HHS) Panel on Antiretroviral Guidelines for Adults and Adolescents, HHS Panel on Antiretroviral Therapy and Medical Management of Children Living with HIV, and HHS Panel on Treatment of Pregnant Women with HIV Infection and Prevention of Perinatal Transmission, have developed comprehensive guidelines that provide information on selection and use of antiretrovirals for the treatment or prevention of HIV infection.200,201,202 Because of the complexity of managing patients with HIV, it is recommended that clinicians with HIV expertise be consulted when needed.200,201,202
The use of combination antiretroviral regimens that generally include 3 drugs from 2 or more drug classes is currently recommended to achieve viral suppression.200,201 In both treatment-naive adults and children, an initial antiretroviral regimen generally consists of 2 NRTIs administered in combination with a third active antiretroviral drug from 1 of 3 drug classes: an INSTI, an NNRTI, or a PI with a pharmacokinetic enhancer (also known as a booster; the 2 drugs used for this purpose are cobicistat and ritonavir).200,201,202 Selection of an initial antiretroviral regimen should be individualized based on factors such as virologic efficacy, toxicity, pill burden, dosing frequency, drug-drug interaction potential, resistance-test results, comorbid conditions, access, and cost.200,201,202 In patients with comorbid infections (e.g., hepatitis B, tuberculosis), antiretroviral regimen selection should also consider the potential for activity against other present infections and timing of initiation relative to other anti-infective regimens.200
Dolutegravir/lamivudine is a co-formulation of an INSTI (dolutegravir) and an NRTI (lamivudine).200 In the 2023 HHS adult and adolescent HIV treatment guideline, dolutegravir/lamivudine is listed among recommended initial regimens for most people with HIV; however, it is not recommended for individuals with HIV RNA >500,000 copies/mL, HBV coinfection, or in whom antiretroviral therapy is to be started before the results of HIV genotypic resistance testing for reverse transcriptase or HBV testing are available.200
In the 2023 HHS pediatric HIV treatment guideline, dolutegravir/lamivudine is not a recommended regimen for children with HIV; data are insufficient to support the use of 2-drug regimens in children at this time.201
In the 2023 HHS perinatal HIV treatment guideline, dolutegravir is included in various antiretroviral regimens.202 Dolutegravir/lamivudine is not recommended for antiretroviral-naive pregnant patients due to lack of data in this patient population; however, if a pregnant patient presents to care on dolutegravir/lamivudine and demonstrates successful maintenance of viral suppression, they can continue the 2-drug regimen with more frequent viral load monitoring (every 1-2 months throughout pregnancy).202
The fixed combination dolutegravir/lamivudine is administered orally once daily with or without food.1
Store dolutegravir/lamivudine tablets below 30°C.1
Fixed-combination tablets of dolutegravir/lamivudine contain dolutegravir sodium and lamivudine; dosages are expressed in terms of dolutegravir and lamivudine, respectively.1
Each fixed-combination tablet of dolutegravir/lamivudine contains 50 mg of dolutegravir and 300 mg of lamivudine.1
For the treatment of human immunodeficiency virus type 1 (HIV-1) infection, the recommended dosage of dolutegravir/lamivudine is 1 tablet (50 mg of dolutegravir and 300 mg of lamivudine) once daily.1
Treatment of HIV-1 Infection in Adults Receiving Carbamazepine or Rifampin
If dolutegravir/lamivudine is used for the treatment of HIV-1 infection in adults receiving carbamazepine or rifampin, patients should receive 1 tablet of the fixed combination (50 mg of dolutegravir and 300 mg of lamivudine) once daily and a 50-mg tablet of single-entity dolutegravir once daily given 12 hours after the fixed-combination tablet.1
Dosage adjustment of dolutegravir/lamivudine is not necessary in adults with mild or moderate hepatic impairment (Child-Pugh class A or B).1
Dolutegravir/lamivudine is not recommended in patients with severe hepatic impairment (Child-Pugh class C).1
Dolutegravir/lamivudine is not recommended in patients with creatinine clearances <30 mL/minute.1
The manufacturer makes no specific dosage recommendations for dolutegravir/lamivudine in geriatric patients, but recommends caution because of possible age-related decreases in hepatic, renal, and/or cardiac function and concomitant disease and drug therapy.1
HIV and Hepatitis B Virus Coinfection
A boxed warning regarding the risk of lamivudine-resistant strains of hepatitis B virus (HBV) in patients coinfected with human immunodeficiency virus type 1 (HIV-1) and exacerbations of HBV is included in the prescribing information of dolutegravir/lamivudine.1 Test all patients with HIV-1 infection for HBV prior to or when initiating dolutegravir/lamivudine.1 Lamivudine-resistant strains of HBV have emerged in patients coinfected with HBV and HIV-1 who were receiving lamivudine-containing antiretroviral regimens.1 In patients with HIV-1 and HBV coinfection, severe acute exacerbations of HBV infection, including liver decompensation and liver failure, have occurred following discontinuance of lamivudine-containing regimens.1 Such reactions could occur following discontinuance of dolutegravir/lamivudine.1 Some experts state that a 2-drug antiretroviral regimen of dolutegravir and lamivudine should not be used in patients coinfected with HBV.200 The manufacturer states that if a decision is made to use dolutegravir/lamivudine in patients coinfected with HIV-1 and HBV, consider appropriate additional treatment for chronic HBV infection; alternatively, consider a different antiretroviral regimen.1 Closely monitor hepatic function with clinical and laboratory follow-up for at least several months after dolutegravir/lamivudine is discontinued in patients coinfected with HIV-1 and HBV.1 If appropriate, initiation of HBV treatment may be warranted, especially in patients with advanced liver disease or cirrhosis.1
Other Warnings and Precautions
Hypersensitivity reactions (e.g., rash, constitutional findings, and, sometimes, organ dysfunction including liver injury) have been reported in patients receiving dolutegravir.1 These adverse effects were reported in <1% of patients receiving dolutegravir in phase 3 clinical trials.1
Discontinue dolutegravir/lamivudine immediately if signs or symptoms of hypersensitivity reactions occur (including, but not limited to, severe rash or rash accompanied by fever, general malaise, fatigue, muscle or joint aches, blisters or peeling of the skin, oral blisters or lesions, conjunctivitis, facial edema, hepatitis, eosinophilia, angioedema, difficulty breathing).1 Monitor clinical status, including liver aminotransferase concentrations, and initiate appropriate therapy.1
Delay in stopping dolutegravir/lamivudine treatment or other suspect agents after onset of a hypersensitivity reaction may result in a life-threatening reaction.1
Adverse hepatic effects have been reported in patients receiving dolutegravir-containing regimens.1
Patients with underlying HBV or hepatitis C virus (HCV) may be at increased risk for development or worsening of serum aminotransferase elevations.1 In some patients receiving a dolutegravir-containing regimen, serum aminotransferase elevations were consistent with immune reconstitution syndrome or HBV reactivation, particularly in the setting where HBV treatment had been discontinued.1
Cases of hepatic toxicity, including elevated serum liver biochemistries, hepatitis, and acute liver failure, also have been reported in patients receiving dolutegravir-containing regimens who had no preexisting hepatic disease or other identifiable risk factors.1 Drug-induced liver injury leading to liver transplantation has been reported with the fixed combination of abacavir, dolutegravir, and lamivudine (abacavir/dolutegravir/lamivudine).1
Monitor for hepatotoxicity in patients receiving dolutegravir/lamivudine.1
Fetal/Neonatal Morbidity and Mortality
Data from an observational study in Botswana showed an association between dolutegravir and an increased risk of neural tube defects when the drug is administered at the time of conception and during early pregnancy.1,10
Because there is only a limited understanding of reported types of neural tube defects associated with dolutegravir use, inform individuals of reproductive potential, including those actively trying to become pregnant, about the potential increased risk of neural tube defects with dolutegravir/lamivudine.1 Assess the risks and benefits of dolutegravir/lamivudine and discuss with the patient to determine if an alternative should be considered at the time of conception through the first trimester of pregnancy or if pregnancy is confirmed in the first trimester.1
Perform pregnancy testing in individuals of reproductive potential before initiation of dolutegravir/lamivudine, and counsel them on the consistent use of effective contraception.1
Dolutegravir/lamivudine may be considered during the second and third trimesters of pregnancy if expected benefits justify potential risks to the pregnant woman and fetus.1
Lactic Acidosis and Severe Hepatomegaly with Steatosis
Lactic acidosis and severe hepatomegaly with steatosis (sometimes fatal) have been reported in patients receiving nucleoside analogs, including lamivudine.1 These cases were reported most frequently in women; obesity also may be a risk factor.1
Monitor closely if dolutegravir/lamivudine is used in patients with known risk factors for liver disease.1
Discontinue dolutegravir/lamivudine in patients who develop clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity (e.g., hepatomegaly and steatosis even in the absence of markedly increased serum aminotransferase concentrations).1
Concomitant use of dolutegravir/lamivudine and certain other drugs may result in known or potentially clinically important drug interactions, some of which may lead to loss of therapeutic effect of dolutegravir/lamivudine and possible development of resistance or result in greater exposures of the concomitant drug.1
Consider the potential for drug interactions prior to and during dolutegravir/lamivudine therapy; review concomitant drugs during dolutegravir/lamivudine therapy and monitor the patient for adverse effects.1
Immune Reconstitution Syndrome
Immune reconstitution syndrome has been reported in patients treated with multiple-drug antiretroviral therapy, including dolutegravir/lamivudine.1 During the initial phase of treatment, HIV-infected patients whose immune systems respond to antiretroviral therapy may develop an inflammatory response to indolent or residual opportunistic infections (e.g., Mycobacterium avium infection, cytomegalovirus [CMV], Pneumocystis jirovecii , tuberculosis); such responses may necessitate further evaluation and treatment.1
Autoimmune disorders (e.g., Graves' disease, polymyositis, Guillain-Barré syndrome) have also been reported to occur in the setting of immune reconstitution; however, the time to onset is more variable, and can occur many months after initiation of antiretroviral therapy.1
When dolutegravir/lamivudine is used, consider the cautions, precautions, contraindications, and drug interactions associated with both drugs in the fixed combination.1
Consider cautionary information applicable to specific populations (e.g., pregnant or nursing women, individuals with hepatic or renal impairment, geriatric patients) for each drug.1
The Antiretroviral Pregnancy Registry (APR) monitors pregnancy outcomes in women exposed to dolutegravir/lamivudine during pregnancy.1 Clinicians are encouraged to register patients in the APR by calling 800-258-4263 or visiting [Web].1,202
Dolutegravir crosses the placenta.1 In a clinical trial conducted in Uganda and South Africa in pregnant women receiving dolutegravir 50 mg once daily in the last trimester, the ratio of median dolutegravir concentration in fetal umbilical cord to that in maternal peripheral plasma was 1.21 (range, 0.51-2.11).1 Lamivudine readily crosses the placenta and concentrations of the drug were generally similar in maternal, neonatal, and umbilical cord serum samples.1
Human data regarding use of dolutegravir/lamivudine in pregnant women are insufficient to definitively assess a drug-associated risk for birth defects and miscarriage associated with the fixed combination.1 Based on prospective reports to the APR of 842 exposures to dolutegravir during pregnancy resulting in live births, the prevalence of defects in live births was 3.3% and 4.8% following first-trimester and second-/third-trimester exposures, respectively, in comparison to the background birth defect rate of 2.7% in the US reference population.1 Based on prospective reports to the APR of over 12,000 exposures to lamivudine during pregnancy resulting in live births (including over 5300 exposures in the first trimester), there was no difference between the overall risk of birth defects for lamivudine compared with the background birth defect rate of 2.7% in the US reference population.1
Interim analyses from an observational birth outcome surveillance study in Botswana (Tsepamo study) showed an increased risk of neural tube defects associated with use of dolutegravir-containing regimens at the time of conception and during early pregnancy compared with use of antiretroviral regimens that did not contain dolutegravir.1,10 Based on these findings, the manufacturer states to advise individuals of reproductive potential, including those actively trying to become pregnant, of the potential risk of neural tube defects.1 Assess the risks and benefits of dolutegravir/lamivudine and discuss with the patient to determine if an alternative treatment should be considered at the time of conception through the first trimester of pregnancy or if pregnancy is confirmed in the first trimester.1 A benefit-risk assessment should consider factors such as the feasibility of switching to a different regimen, tolerability, ability to maintain viral suppression, and risk of HIV-1 transmission to the infant versus the risk of neural tube defects.1 Use of dolutegravir/lamivudine may be considered during the second and third trimesters of pregnancy if expected benefits justify potential risks to the pregnant woman and fetus.1
The Health and Human Services (HHS) Panel on Treatment of Pregnant Women with HIV Infection and Prevention of Perinatal Transmission reports that more recent data from Botswana indicate that the prevalence of neural tube defects in infants born to pregnant women with HIV receiving dolutegravir at conception is no longer statistically different than in those receiving other antiretrovirals.202 The HHS states that data are not available regarding use of 2-drug regimens for the treatment of HIV-1 infection during pregnancy and, therefore, a 2-drug regimen of dolutegravir/lamivudine is not recommended as a complete treatment regimen in antiretroviral-naive or antiretroviral-experienced pregnant women or women of reproductive potential trying to conceive.202
Dolutegravir and lamivudine are distributed into human milk.1 It is not known whether dolutegravir/lamivudine or its components affect human milk production or affect the breast-fed infant.1
The Centers for Disease Control and Prevention and the HHS state that HIV-infected women should not breast-feed infants.1,202 This is because of the potential for HIV‑1 transmission in HIV-negative infants, development of viral resistance in HIV-positive infants, and adverse reactions in the breast-fed infant.1
Females and Males of Reproductive Potential
Perform pregnancy testing in all individuals of reproductive potential before initiation of dolutegravir/lamivudine.1
In individuals of reproductive potential currently on dolutegravir/lamivudine who are actively trying to become pregnant or if pregnancy is confirmed in the first trimester, assess the risks and benefits of continuing dolutegravir/lamivudine and discuss with the patient if an alternative treatment should be considered.1
Advise individuals of reproductive potential to consistently use effective contraception during dolutegravir/lamivudine therapy.1
The safety and efficacy of dolutegravir/lamivudine have not been established in pediatric patients.1
Clinical trials of dolutegravir/lamivudine did not include a sufficient number of patients ≥65 years of age to determine whether they respond differently compared with younger patients.1
Use dolutegravir/lamivudine with caution in geriatric patients because of age-related decreases in hepatic, renal, and/or cardiac function and potential for concomitant disease and drug therapy.1
Dosage adjustment of dolutegravir/lamivudine is not necessary in patients with mild or moderate hepatic impairment (Child-Pugh class A or B).1
Dolutegravir has not been studied in patients with severe hepatic impairment (Child-Pugh class C); therefore, dolutegravir/lamivudine is not recommended in those with severe hepatic impairment.1
Dolutegravir/lamivudine is not recommended in patients with creatinine clearances <30 mL/minute because dolutegravir/lamivudine is a fixed-dose combination preparation and dosage of its components cannot be adjusted individually.1 Use single-entity dolutegravir and single-entity lamivudine in patients with creatinine clearances <30 mL/minute if a reduction of lamivudine dosage is required in such patients.1
Patients with a creatinine clearance between 30-49 mL/minute receiving dolutegravir/lamivudine may experience a 1.6-3.3-fold higher lamivudine exposure (AUC) than patients with a creatinine clearance ≥50 mL/minute.1 Patients with a sustained creatinine clearance between 30-49 mL/minute who receive dolutegravir/lamivudine should be monitored for hematologic toxicities.1 If new or worsening neutropenia or anemia develop, adjust the dosage of lamivudine per the prescribing information for lamivudine.1 If lamivudine dose adjustment is indicated, discontinue dolutegravir/lamivudine and use single-entity dolutegravir and single-entity lamivudine to construct the treatment regimen.1
Adverse effects reported in 2% or more of patients receiving dolutegravir/lamivudine include headache, nausea, diarrhea, insomnia, fatigue, and anxiety.1,2
The following drug interactions are based on studies using the individual components of the fixed combination of dolutegravir and lamivudine (dolutegravir/lamivudine) or are predicted to occur with the fixed combination.1 When dolutegravir/lamivudine is used, consider interactions associated with both drugs in the fixed combination.1
Drugs Affecting or Metabolized by Hepatic Microsomal Enzymes
Cytochrome P-450 (CYP) isoenzyme 3A plays a minor role in the metabolism of dolutegravir;1 lamivudine is not metabolized by CYP isoenzymes to any clinically important extent.1,219
In vitro studies indicate that dolutegravir does not inhibit CYP isoenzymes 1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, or 3A and does not induce CYP1A2, 2B6, or 3A4.1
Concomitant use of dolutegravir and drugs that induce CYP3A may decrease dolutegravir plasma concentrations and decrease therapeutic effects of the drug.1 Concomitant use with drugs that inhibit CYP3A may increase dolutegravir plasma concentrations.1
Drugs Affecting or Metabolized by Uridine Diphosphate-glucuronosyltransferases
Dolutegravir is metabolized by uridine diphosphate-glucuronosyltransferase (UGT) 1A1, and in vitro studies indicate the drug also is a substrate for UGT1A3 and UGT1A9.1
Dolutegravir does not inhibit UGT1A1 or UGT2B7 in vitro.1
Pharmacokinetic interactions are possible if dolutegravir is used with inducers of UGT1A1, 1A3, or 1A9 (decreased plasma concentrations of dolutegravir and decreased therapeutic effects of the drug) or with inhibitors of these enzymes (increased plasma concentrations of dolutegravir).1
Drugs Affecting or Affected by P-glycoprotein Transport
Dolutegravir is a substrate of the P-glycoprotein (P-gp) transport system in vitro; dolutegravir does not inhibit P-gp-mediated transport in vitro.1
Pharmacokinetic interactions are possible if dolutegravir is used with inducers of P-gp (decreased plasma concentrations of dolutegravir and decreased therapeutic effects of the drug) or with inhibitors of P-gp (increased plasma concentrations of dolutegravir).1
Although lamivudine is a substrate of P-gp,1,219 concomitant use with P-gp inhibitors is unlikely to affect lamivudine concentrations.219 Lamivudine does not inhibit P-gp in vitro1 and is not expected to affect the pharmacokinetics of drugs that are P-gp substrates.219
Drugs Affecting or Affected by Bile Salt Export Pump
Dolutegravir does not inhibit the bile salt export pump (BSEP) in vitro.1
Drugs Affecting or Affected by Breast Cancer Resistance Protein
Dolutegravir is a substrate of breast cancer resistance protein (BCRP) in vitro; dolutegravir does not inhibit BCRP in vitro.1
Pharmacokinetic interactions are possible if dolutegravir is used with inducers of BCRP (decreased plasma concentrations of dolutegravir and decreased therapeutic effects of the drug) or with inhibitors of BCRP (increased plasma concentrations of dolutegravir).1
Although lamivudine is a substrate of BCRP,1,219 concomitant use with BCRP inhibitors is unlikely to affect lamivudine concentrations.219 Lamivudine does not inhibit BCRP in vitro1 and is not expected to affect the pharmacokinetics of drugs that are BCRP substrates.219
Drugs Affecting or Affected by Multidrug and Toxin Extrusion Transporter
Dolutegravir inhibits multidrug and toxin extrusion transporter (MATE) 1 in vitro.1
Concomitant use of dolutegravir may increase plasma concentrations of drugs eliminated by MATE1 (e.g., dofetilide, metformin).1
Lamivudine is a substrate of MATE1 and MATE2-K in vitro.219 Although inhibitors of MATE1 or MATE2-K may increase lamivudine concentrations, this effect is not considered clinically important.219 Lamivudine does not inhibit MATE1 or MATE2-K in vitro and is not expected to affect the pharmacokinetics of drugs that are MATE-1 or MATE2-K substrates.219
Drugs Affecting or Affected by Multidrug Resistance Protein
Dolutegravir does not inhibit multidrug resistance protein (MRP) 2 or MRP4 in vitro.1
Drugs Affecting or Affected by Organic Anion Transporters
In vitro, dolutegravir inhibits renal organic anion transporter (OAT) 1 and OAT3.1 In vivo, dolutegravir does not alter plasma concentrations of OAT1 or OAT3 substrates (e.g., tenofovir, aminohippurate).1
Dolutegravir does not inhibit hepatic organic anion transporter polypeptide (OATP) 1B1 or OATP1B3 in vitro; dolutegravir is not a substrate of OATP1B1 or 1B3 in vitro.1
Lamivudine does not inhibit OATP1B1/3 in vitro1 and is not expected to affect the pharmacokinetics of drugs that are OATP1B1/3 substrates.219
Drugs Affecting or Affected by Organic Cation Transporters
In vitro, dolutegravir inhibits renal organic cation transporter (OCT) 2; dolutegravir does not inhibit OCT1 in vitro.1
Dolutegravir may increase plasma concentrations of drugs eliminated by OCT2 (e.g., dalfampridine, dofetilide, metformin).1
Lamivudine is a substrate of OCT2 in vitro.219 Although inhibitors of OCT2 may increase lamivudine concentrations, this effect is not considered clinically important.219 Lamivudine does not inhibit OCT1, OCT2, or OCT3 in vitro1 and is not expected to affect the pharmacokinetics of drugs that are OCT1, OCT2, or OCT3 substrates.219
Concomitant use of carbamazepine (300 mg twice daily) and dolutegravir (50 mg once daily) decreases peak plasma concentrations and area under the plasma concentration-time curve (AUC) of dolutegravir.1
If carbamazepine and dolutegravir/lamivudine are used concomitantly, administer a 50-mg dose of single-entity dolutegravir once daily 12 hours after the usual daily dose of dolutegravir/lamivudine.1
Oxcarbazepine, Phenobarbital, and Phenytoin
Possible pharmacokinetic interactions if oxcarbazepine, phenobarbital, or phenytoin is used concomitantly with dolutegravir (decreased dolutegravir concentrations).1
Avoid concomitant use of oxcarbazepine, phenobarbital, or phenytoin and dolutegravir/lamivudine since data are insufficient to make dosage recommendations.1
Rifabutin does not have a clinically important effect on the pharmacokinetics of dolutegravir.1
Concomitant use of rifampin and dolutegravir decreases plasma concentrations and AUC of dolutegravir.1
If rifampin and dolutegravir/lamivudine are used concomitantly, administer a 50-mg dose of single-entity dolutegravir once daily 12 hours after the usual daily dose of dolutegravir/lamivudine.1
Clinically important decreases in dolutegravir plasma concentrations are expected if rifapentine and dolutegravir are used concomitantly.200
Rifapentine and dolutegravir should not be used concomitantly.200
Dolutegravir/lamivudine is a complete regimen for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in certain adults, and the manufacturer states that concomitant use with other antiretroviral agents is not recommended.1
There is no in vitro evidence of antagonistic antiretroviral effects between dolutegravir and lamivudine.1
Calcium, Iron, Multivitamins, and Other Preparations Containing Polyvalent Cations
Calcium, Iron, and Multivitamins
Concomitant administration of oral calcium supplements, oral iron preparations, or other oral supplements containing calcium or iron (e.g., multivitamins) and dolutegravir in the fasted state may decrease absorption of dolutegravir resulting in decreased plasma concentrations and AUC of the drug.1
Administer dolutegravir/lamivudine at least 2 hours before or 6 hours after oral supplements containing calcium or iron.1 Alternatively, if dolutegravir/lamivudine is administered with food, the drug can be used concomitantly with oral supplements containing calcium or iron.1
Preparations Containing Polyvalent Cations
Concomitant administration of drugs containing polyvalent cations (e.g., magnesium, aluminum, laxatives, buffered medications, cation-containing products) with dolutegravir in the fasted state may decrease absorption of dolutegravir resulting in decreased plasma concentrations of the drug.1
Administer dolutegravir/lamivudine at least 2 hours before or 6 hours after drugs or preparations containing polyvalent cations.1
Pharmacokinetic interactions are possible if dolutegravir is used concomitantly with bosentan (decreased dolutegravir concentrations); some experts state that dosage adjustments are not needed if bosentan and dolutegravir are used concomitantly.200
Concomitant use of dalfampridine and dolutegravir/lamivudine may result in increased dalfampridine concentrations and may increase the risk of seizures.1 Weigh the potential benefits of concomitant use of dalfampridine and dolutegravir/lamivudine against the risk of seizures.1
Concomitant use of dofetilide and dolutegravir/lamivudine may increase dofetilide plasma concentrations and increase the risk of serious and/or life-threatening adverse effects.1
Concomitant use of dofetilide and dolutegravir/lamivudine is contraindicated.1
Antacids containing aluminum, calcium, or magnesium decrease plasma concentrations and AUC of dolutegravir.1
Administer dolutegravir/lamivudine at least 2 hours before or 6 hours after antacids containing aluminum, calcium, or magnesium.1
Sucralfate may decrease plasma concentrations of dolutegravir.1
Administer dolutegravir/lamivudine at least 2 hours before or 6 hours after sucralfate.1
Concomitant use of interferon alfa and lamivudine does not have any clinically important effects on the pharmacokinetics of lamivudine.1
Concomitant use of metformin hydrochloride (500 mg twice daily) and dolutegravir (50 mg once or twice daily) increases peak plasma concentrations and AUC of metformin.1 If concomitant use of metformin and dolutegravir/lamivudine is being considered, assess the benefits and risks.3
Some experts recommend that if metformin is initiated in a patient receiving dolutegravir, the lowest metformin dosage should be used and dosage should be titrated based on glycemic control while monitoring for metformin-associated adverse effects.200 When initiating or discontinuing dolutegravir in patients receiving metformin, dosage of metformin may need to be adjusted to maintain optimal glycemic control and/or minimize metformin-associated adverse effects.200
Dolutegravir does not have a clinically important effect on the pharmacokinetics of methadone;1 dosage adjustments are not needed if methadone and dolutegravir are used concomitantly.200
Concomitant use of lamivudine and sorbitol decreases plasma concentrations and AUC of lamivudine.1
Avoid concomitant use of dolutegravir/lamivudine and sorbitol-containing drugs.1
Concomitant use of St. John's wort ( Hypericum perforatum ) and dolutegravir may decrease dolutegravir plasma concentrations.1
Avoid concomitant use of St. John's wort and dolutegravir/lamivudine; data are insufficient to make dosage recommendations.1
Dolutegravir sodium and lamivudine (dolutegravir/lamivudine) is a fixed combination containing 2 human immunodeficiency virus (HIV) antiretrovirals.1 Dolutegravir is an HIV integrase strand transfer inhibitor (INSTI) and lamivudine is an HIV nucleoside reverse transcriptase inhibitor (NRTI).1 There is no in vitro evidence of antagonistic anti-HIV effects between dolutegravir and lamivudine.1
Dolutegravir binds to the active site of HIV integrase and blocks the strand transfer step of retroviral DNA integration, which is essential for HIV replication.1 Dolutegravir is active against HIV type 1 (HIV-1)1 and also has in vitro activity against HIV type 2 (HIV-2).200
Lamivudine is a prodrug that is phosphorylated intracellularly to the active 5'-triphosphate metabolite (lamivudine triphosphate).1,219 After conversion to the pharmacologically active metabolite, the drug acts as a reverse transcriptase inhibitor via DNA chain termination after incorporation of the nucleotide analogue.1,219 Lamivudine is active against HIV-11,219 and also is active against hepatitis B virus (HBV).200
Strains of HIV-1 resistant to dolutegravir have been produced in vitro and have emerged in HIV-infected patients receiving the drug; amino acid substitution G118R confers a tenfold decrease in in vitro susceptibility to dolutegravir.1 Strains of HIV-1 resistant to lamivudine have been produced in vitro and have emerged in HIV-infected patients receiving lamivudine-containing regimens; HIV-1 resistance to lamivudine often involves amino acid substitutions M184V or M184I.1,219 In a phase 3 clinical study evaluating a 2-drug regimen of dolutegravir and lamivudine in antiretroviral-naive adults, treatment-emergent INSTI- or NRTI-resistance substitutions were not reported in any patients at 48, 96, or 144 weeks.1,2,3 In preliminary studies evaluating a 2-drug regimen of dolutegravir and lamivudine for switch therapy in previously treated HIV-1-infected adults, emergence of dolutegravir resistance-associated mutations was not reported4,6,7,11 and presence of the M184V lamivudine resistance-associated mutation was not a predictor of virologic failure.6,7 In a phase 3 clinical study evaluating a 2-drug regimen of dolutegravir and lamivudine in virologically suppressed patients, no patients met the protocol-defined confirmed virologic withdrawal criteria through week 144.1 No emergent INSTI- or NRTI-resistance was detected by genotypic or phenotypic analyses of the last on-treatment isolate from 1 patient who received dolutegravir/lamivudine with HIV-1 RNA ≥400 copies/mL at withdrawal.1 Cross-resistance occurs among HIV INSTIs (e.g., dolutegravir, elvitegravir, raltegravir).1 Cross-resistance also occurs among HIV NRTIs (e.g., abacavir, emtricitabine, lamivudine, zidovudine).1
Following oral administration of dolutegravir in the fasted state, peak plasma concentrations of the drug are attained 2.5 hours after a dose;1 absolute oral bioavailability has not been established.236 Dolutegravir is metabolized primarily by uridine diphosphate-glucuronosyltransferase (UGT) 1A1; cytochrome P-450 (CYP) isoenzyme 3A plays only a minor role in metabolism of the drug.1 Following an oral dose of dolutegravir, 64% of the dose is eliminated in feces (53% as unchanged drug) and 31% is eliminated in urine (<1% as unchanged drug).1 Dolutegravir has a plasma elimination half-life of approximately 14 hours.1 In vitro studies indicate that dolutegravir is approximately 99% bound to plasma proteins.1
Following oral administration of lamivudine in the fasted state, peak plasma concentrations of the drug are attained 1 hour after a dose1 and absolute oral bioavailability is 86%.219 Lamivudine is principally eliminated in urine by active cationic secretion; approximately 71% of a dose is eliminated in urine.1,219 Lamivudine is not significantly metabolized and is not metabolized by CYP isoenzymes to any clinically important extent.1,219 Lamivudine has a plasma elimination half-life of 13-19 hours.1 Lamivudine is 36% bound to plasma proteins.1
Administration of dolutegravir/lamivudine with a high-fat meal does not have a clinically important effect on the pharmacokinetics of either component.1 No clinically significant differences in the pharmacokinetics of dolutegravir or lamivudine have been observed based on age, sex, or race.1 Lamivudine pharmacokinetics in pregnant women are similar to those observed in non-pregnant and postpartum women.1
Additional Information
The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer's labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.
Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.
Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.
Routes | Dosage Forms | Strengths | Brand Names | Manufacturer |
---|---|---|---|---|
Oral | Tablets, film-coated | 50 mg (of dolutegravir) and Lamivudine 300 mg | Dovato® | ViiV |
AHFS® Drug Information. © Copyright, 1959-2024, Selected Revisions March 10, 2024. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, MD 20814.
1. ViiV Healthcare. Dovato® (dolutegravir sodium and lamivudine) tablets prescribing information. Research Triangle Park, NC; 2023 Jan.
2. Cahn P, Madero JS, Arribas JR et al. Dolutegravir plus lamivudine versus dolutegravir plus tenofovir disoproxil fumarate and emtricitabine in antiretroviral-naive adults with HIV-1 infection (GEMINI-1 and GEMINI-2): week 48 results from two multicentre, double-blind, randomised, non-inferiority, phase 3 trials. Lancet . 2019; 393:143-155. [PubMed 30420123]
3. Cahn P, Madero JS, Arribas JR et al. Three-year durable efficacy of dolutegravir plus lamivudine in antiretroviral therapy - naive adults with HIV-1 infection.. AIDS . 2022; 36:39-48.
4. Joly V, Burdet C, Landman R et al. Dolutegravir and lamivudine maintenance therapy in HIV-1 virologically suppressed patients: results of the ANRS 167 trial (LAMIDOL). J Antimicrob Chemother . 2019; 74:739-745. [PubMed 30476165]
5. Taiwo BO, Marconi VC, Berzins B et al. Dolutegravir Plus Lamivudine Maintains Human Immunodeficiency Virus-1 Suppression Through Week 48 in a Pilot Randomized Trial. Clin Infect Dis . 2018; 66:1794-1797. [PubMed 29293895]
6. Baldin G, Ciccullo A, Rusconi S et al. Long-term data on the efficacy and tolerability of lamivudine plus dolutegravir as a switch strategy in a multi-centre cohort of HIV-1-infected, virologically suppressed patients. Int J Antimicrob Agents . 2019; [PubMed 31521809]
7. Baldin G, Ciccullo A, Borghetti A et al. Virological efficacy of dual therapy with lamivudine and dolutegravir in HIV-1-infected virologically suppressed patients: long-term data from clinical practice. J Antimicrob Chemother . 2019; 74:1461-1463. [PubMed 30726922]
9. Dumitrescu TP, Peddiraju K, Fu C et al. Bioequivalence and Food Effect Assessment of 2 Fixed-Dose Combination Formulations of Dolutegravir and Lamivudine. Clin Pharmacol Drug Dev . 2019; [PubMed 31724343]
10. Zash R, Holmes L, Diseko M et al. Neural-Tube Defects and Antiretroviral Treatment Regimens in Botswana. N Engl J Med . 2019; 381:827-840. [PubMed 31329379]
11. Maggiolo F, Gulminetti R, Pagnucco L et al. Lamivudine/dolutegravir dual therapy in HIV-infected, virologically suppressed patients. BMC Infect Dis . 2017; 17:215. [PubMed 28302065]
12. van Wyk J, Ajana F, Bisshop F et al. Efficacy and safety of switching to dolutegravir/lamivudine fixed-dose two-drug regimen versus continuing a tenofovir alafenamide-based three- or four-drug rgimen for maintenance of virologic suppression in adults with HIV-1: phase 3, randomized, non-inferiority TANGO study. Clin Infect Dis . 2020; [PubMed 31905383]
14. Osiyemi O, De Wit S, Ajana F, et al. Efficacy and Safety of Switching to Dolutegravir/Lamivudine Versus Continuing a Tenofovir Alafenamide-Based 3- or 4-Drug Regimen for Maintenance of Virologic Suppression in Adults Living With Human Immunodeficiency Virus Type 1: Results Through Week 144 From the Phase 3, Noninferiority TANGO Randomized Trial. Clin Infect Dis. 2022;75(6):975-986.
15. Llibre JM, Brites C, Cheng CY, et al. Efficacy and Safety of Switching to the 2-Drug Regimen Dolutegravir/Lamivudine Versus Continuing a 3- or 4-Drug Regimen for Maintaining Virologic Suppression in Adults Living With Human Immunodeficiency Virus 1 (HIV-1): Week 48 Results From the Phase 3, Noninferiority SALSA Randomized Trial. Clin Infect Dis. 2023;76(4):720-729.
200. Panel on Antiretroviral Guidelines for Adults and Adolescents, US Department of Health and Human Services (HHS). Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents (March 23, 2023). Updates may be available at HIV.gov website. [Web]
201. Panel on Antiretroviral Therapy and Medical Management of HIV-1-infected Children. US Department of Health and Human Services (HHS). Guidelines for the use of antiretroviral agents in pediatric HIV infection (January 31, 2023). Updates may be available at HIV.gov website. [Web]
202. Panel on Treatment of Pregnant Women with HIV Infection and Prevention of Perinatal Transmission, US Department of Health and Human Services (HHS). Recommendations for the use of antiretroviral drugs in pregnant women with HIV infection and interventions to reduce perinatal HIV transmission in the United States (January 31, 2023). Updates may be available at HIV.gov website. [Web]
219. ViiV Healthcare. Epivir® (lamivudine) tablet, film coated and solution prescribing information. Research Triangle Park, NC; 2020 Sep.
236. ViiV Healthcare. Tivicay® (dolutegravir) tablets prescribing information. Durham, NC; 2022 Oct.