IC50: 2.7 nM (HIV-1 integrase)[1]

Dolutegravir (S/GSK1349572) has an EC50 of 0.51 nM against HIV-1 in PBMCs, 0.71 nM in MT-4 cells, and 2.2 nM in the pseudotyped self-inactivating virus (PHIV) assay. Dolutegravir's 50% cytotoxic concentrations (CC50) in proliferating IM-9, U-937, MT-4, and Molt-4 cells are, in order, 4.8, 7.0, 14, and 15 μM. The CC50 values in unstimulated and stimulated PBMCs are 189 μM and 52 μM, in that order. Dolutegravir's 0.51 nM EC50 against HIV-1 in PBMCs indicates that a cell-based therapeutic index of at least 9,400 is required[1].

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S/GSK1349572 is a next-generation HIV integrase (IN) inhibitor designed to deliver potent antiviral activity with a low-milligram once-daily dose requiring no pharmacokinetic (PK) booster. In addition, S/GSK1349572 demonstrates activity against clinically relevant IN mutant viruses and has potential for a high genetic barrier to resistance. S/GSK1349572 is a two-metal-binding HIV integrase strand transfer inhibitor whose mechanism of action was established through in vitro integrase enzyme assays, resistance passage experiments, activity against viral strains resistant to other classes of anti-HIV agents, and mechanistic cellular assays. In a variety of cellular antiviral assays, S/GSK1349572 inhibited HIV replication with low-nanomolar or subnanomolar potency and with a selectivity index of 9,400. The protein-adjusted half-maximal effective concentration (PA-EC(50)) extrapolated to 100% human serum was 38 nM. When virus was passaged in the presence of S/GSK1349572, highly resistant mutants were not selected, but mutations that effected a low fold change (FC) in the EC(50) (up to 4.1 fold) were identified in the vicinity of the integrase active site. S/GSK1349572 demonstrated activity against site-directed molecular clones containing the raltegravir-resistant signature mutations Y143R, Q148K, N155H, and G140S/Q148H (FCs, 1.4, 1.1, 1.2, and 2.6, respectively), while these mutants led to a high FC in the EC(50) of raltegravir (11- to >130-fold). Either additive or synergistic effects were observed when S/GSK1349572 was tested in combination with representative approved antiretroviral agents; no antagonistic effects were seen. These findings demonstrate that S/GSK1349572 would be classified as a next-generation drug in the integrase inhibitor class, with a resistance profile markedly different from that of first-generation integrase inhibitors[1].

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Raltegravir (RAL) and related HIV-1 integrase (IN) strand transfer inhibitors (INSTIs) efficiently block viral replication in vitro and suppress viremia in patients. These small molecules bind to the IN active site, causing it to disengage from the deoxyadenosine at the 3' end of viral DNA. The emergence of viral strains that are highly resistant to RAL underscores the pressing need to develop INSTIs with improved resistance profiles. Herein, we show that the candidate second-generation drug dolutegravir (DTG, S/GSK1349572) effectively inhibits a panel of HIV-1 IN variants resistant to first-generation INSTIs. To elucidate the structural basis for the increased potency of DTG against RAL-resistant INs, we determined crystal structures of wild-type and mutant prototype foamy virus intasomes bound to this compound. The overall IN binding mode of DTG is strikingly similar to that of the tricyclic hydroxypyrrole MK-2048. Both second-generation INSTIs occupy almost the same physical space within the IN active site and make contacts with the β4-α2 loop of the catalytic core domain. The extended linker region connecting the metal chelating core and the halobenzyl group of DTG allows it to enter farther into the pocket vacated by the displaced viral DNA base and to make more intimate contacts with viral DNA, compared with those made by RAL and other INSTIs. In addition, our structures suggest that DTG has the ability to subtly readjust its position and conformation in response to structural changes in the active sites of RAL-resistant INs[2].

In rats (0.23 mL/min/kg) and monkeys (2.12 mL/min/kg), the plasma clearance after a single intravenous (IV) dose of dolutegravir is low. Both the rat and monkey have half-lives of roughly six hours, and their steady-state volume of distribution (VSS) is small. When given orally as a solution to one male monkey and five fast-fasting rats, dolutegravir is highly bioavailable and quickly absorbed (75.6 and 87.0%, respectively). After oral administration of a suspension to non-fasted rats up to 250 mg/kg and non-fasted monkeys up to 50 mg/kg, dolutegravir exposure (Cmax and AUC) increased with increasing dose, however the rise is less than proportional[3].

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1. Plasma clearance of dolutegravir, an unboosted HIV-1 integrase inhibitor, was low in rat and monkey (0.23 and 2.12 mL/min/kg, respectively) as was the volume of distribution (0.1 and 0.28 L/kg, respectively) with terminal elimination half-life approximately 6 h. Dolutegravir was rapidly absorbed from oral solution with a high bioavailability in rat and monkey (75.6 and 87.0% respectively), but solubility or dissolution rate limited when administered as suspension. 2. Dolutegravir was highly bound (>99%) to serum proteins in rat and monkey, similar to binding to plasma and serum proteins in human. Radioactivity was associated with the plasma versus cellular components of blood across all species. 3. Following oral administration to rats, [(14)C]dolutegravir-related radioactivity was distributed to most tissues, due in part to high permeability; however, because of high plasma protein binding, tissue to blood ratios were low. In mouse, rat and monkey, the absorbed dose was extensively metabolized and secreted into bile, with the majority of the administered radioactivity eliminated in feces within 24 h. 4. The primary route of metabolism of dolutegravir was through the formation of an ether glucuronide. Additional biotransformation pathways: benzylic oxidation followed by hydrolysis to an N-dealkylated product, glucose conjugation, oxidative defluorination, and glutathione conjugation[3].

In vitro strand transfer assay.
The inhibitory potencies of S/GSK1349572 and other INIs were measured in a strand transfer assay using recombinant HIV integrase as previously described (5). A complex of integrase and biotinylated preprocessed donor DNA-streptavidin-coated Acintillation proximity assay (SPA) beads was formed by incubating 2 μM purified recombinant integrase with 0.66 μM biotinylated donor DNA-4 mg/ml streptavidin-coated SPA beads in 25 mM sodium morpholinepropanesulfonic acid (MOPS) (pH 7.2), 23 mM NaCl, and 10 mM MgCl2 for 5 min at 37°C. These beads were spun down and preincubated with diluted INIs for 60 min at 37°C. Then a 3H-labeled target DNA substrate was added to give a final concentration of 7 nM substrate, and the strand transfer reaction mixture was incubated at 37°C for 25 to 45 min, which allowed for a linear increase in the strand transfer of donor DNA to radiolabeled target DNA. The signal was read using a Wallac MicroBeta scintillation plate reader [1].

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PHIV assay. [1]
The antiviral activities of compounds were measured in a single-round assay using a self-inactivating PHIV lentiviral vector. CIP4 cells (2 × 104 cells/well) were infected with PHIV sufficient to produce approximately 50,000 relative light units in the assay. The infected cells were added to 96-well, black, clear-bottom plates with various concentrations of Dolutegravir (GSK1349572) and incubated for 2 days. Luciferase activity was measured in a luminometer using the Steady-Glo reagent.

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Effect of human serum and serum proteins. [1]
The effect of the presence of human serum albumin (HSA) (20 or 40 mg/ml), α1-acid glycoprotein (AAG) (2 mg/ml), and human serum (HS) (using up to 30% or 50% and extrapolated to 100%) on the antiviral activity of Dolutegravir (GSK1349572) was evaluated in PHIV and MT-4 assay systems. To estimate the effects of protein binding, antiviral activity was tested with the addition of various concentrations of human serum to an HIV replication assay in MT-4 cells as previously described. The protein-adjusted half-maximal effective concentration (PA-EC50) was estimated by multiplying the EC50 in PBMCs by the fold-shift value.

Antiviral assay in MT-4 cells.[1]
MT-4 cells growing exponentially at a density of 5 × 105 or 6 × 105/ml were infected with HIV-1 strain IIIB at a viral multiplicity of infection of 0.001 or a 50% tissue culture infective dose of 4 to 10. The cells were then aliquoted to 96-well plates in the presence of varying concentrations of compounds. After incubation for 4 or 5 days, antiviral activity was determined by a cell viability assay that either measured bioluminescence with a CellTiter-Glo luminescent reagent or measured absorbance at 560 and 690 nm using the yellow tetrazolium MTT reagent [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide].

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Antiviral assay in PBMCs.[1]
In one 96-well culture plate, PHA- and IL-2-stimulated PBMCs (4 × 105/well) were preincubated with a compound for 1 h, while HIV-1 strain Ba-L was mixed with the same compound in a second plate. An aliquot of the Ba-L-compound mixture was then transferred to the PBMC-compound mixture and was incubated for 7 days. After this incubation, supernatants were assayed for reverse transcriptase (RT) activity by incorporation of [methyl-3H]dTTP to measure viral replication as previously described.

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Cytotoxicity assays.[1]
In vitro growth inhibition (cytotoxicity) studies were conducted with S/GSK1349572 in proliferating human leukemic and lymphomic cell lines (IM-9, U-937, MT-4, and Molt-4) as well as in stimulated and unstimulated human PBMCs. ATP levels were quantified by using the CellTiter-Glo luciferase reagent to measure the ability of a compound to inhibit cell growth as an indicator of the compound's potential for cytotoxicity.

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Mechanistic cellular studies.[1]
To determine if S/GSK1349572 was inhibiting HIV replication in cellular assays through an integrase inhibition mechanism, the effects on the synthesis of HIV NL432 DNA species in MT-4 cells were measured in a single-round infection assay using quantitative PCR methods. Quantitative PCR analysis was performed to measure the synthesis of HIV DNA species in MT-4 cells in the presence of an INI or NNRTI as described previously, with minor modifications. Briefly, 293T cells were transfected with the NL432 plasmid to generate infectious virus, and the supernatant was filtered through 0.45-μm-pore-size filters and was treated with DNase I. MT-4 cells were infected with HIV-1 NL432 for 1 h, incubated with dilutions of a compound, and collected after 6 or 18 h of incubation. All cells were incubated with 0.5 μM ritonavir in order to limit HIV replication to a single cycle. Total-DNA PCR to detect late RT products was performed by incubating the samples for 6 h. Nested Alu-PCR to detect integrated provirus and 2-LTR PCR to detect 2-LTR circles were performed by incubating the samples for 18 h. Reaction products were analyzed using the ABI Prism 7900HT-3 sequence detection system

For rat and monkey PK studies, Dolutegravir is administered as the free acid or the sodium salt. All doses are presented in terms of the free acid. Dolutegravir is administered by intravenous (IV) short-term (within 2 min) bolus (1 mg/kg) to three male rats and two male monkeys. For single oral administration, Dolutegravir as a solution (5 mg/kg) is administered to three fasted male rats and two fasted male monkeys. Dolutegravir is administered as single oral doses of 5, 50, 100, and 250 mg/kg to non-fasted male rats (n=2/dose level) and 3, 10, and 50 mg/kg to non-fasted female monkeys. For intravenous administration, blood samples are collected from rats (0.2 mL via jugular vein cannula) and monkeys (approximately 0.2 or 0.5 mL via saphenous vein in a hindlimb) into Na2EDTA-treated syringes at 0.083, 0.25, 0.5, 1, 2, 4, 6, 8, and 24 h. For oral administration, samples are collected at 0.25 (rats only), 0.5, 1, 2, 4, 6 [rats (solution and suspension) and monkey (solution only)], 8, and 24 h. Following collection, the blood is immediately put on wet ice and then centrifuged within an hour at 1740 g for 10 min at 4°C to obtain plasma. All samples are stored at approximately -20°C or colder prior to analysis by using a method based on protein precipitation and LC-MS/MS analysis.[1]

2.7 mg/kg/day; administrated orally for two weeks.

C57BL/6 mice

Absorption, Distribution and Excretion
When HIV-1-infected adults are given 50 mg dolutegravir orally daily, the AUC, Cmax, and Cmin are 53.6 mcg·h/mL, 3.67 mcg/mL, and 1.11 mcg/mL, respectively. Peak plasma concentrations are reached 2 to 3 hours after administration. Steady-state is reached in approximately 5 days, with a mean cumulative ratio of AUC, Cmax, and C24h of 1.2 to 1.5. When pediatric patients (12 to < 18 years of age and weighing ≥ 40 kg) are given 50 mg once daily, the Cmax, AUC, and C24h are 3.49 mcg/mL, 46 mcg·h/mL, and 0.90 mcg/mL, respectively. Almost all doses of dolutegravir are recoverable after a single oral dose, with 53% excreted unchanged in feces and 31% in urine. The renal clearance and recovery of dolutegravir ether glucuronide (18.9%), benzylic carbon oxidation metabolite (3.0%), hydrolyzed N-dealkylation product (3.6%), and unchanged drug (<1%). The apparent volume of distribution for 50 mg dolutegravir was 17.4 L. After 2 weeks of treatment, the median concentration of dolutegravir in cerebrospinal fluid was 18 ng/mL. The apparent clearance of dolutegravir was 1.0 L/h. Following a single oral [14C]dolutegravir dose, 53% of the total oral dose was excreted unchanged in feces. 31% of the total oral dose was excreted in urine, primarily as dolutegravir ether glucuronide (18.9% of the total dose), benzylic carbon oxidation metabolite (3.0% of the total dose), and its hydrolyzed N-dealkylation product (3.6% of the total dose). The original drug has low renal clearance (<1%). Based on in vivo data, dolutegravir has a high binding rate to human plasma proteins (=98.9%), independent of plasma dolutegravir concentration. Based on population pharmacokinetic analysis, the apparent volume of distribution (Vd/F) after a once-daily 50 mg dose is estimated to be 17.4 L. Food increases the extent of dolutegravir absorption and slows its absorption rate. Low-fat, medium-fat, and high-fat diets increased the AUC(0-8) of dolutegravir by 33%, 41%, and 66%, respectively; in the fasting state, dolutegravir increased Cmax by 46%, 52%, and 67%, respectively; and prolonged Tmax from 2 hours to 3 hours, 4 hours, and 5 hours, respectively. Peak plasma concentrations occur 2 to 3 hours after oral dolutegravir administration. Following once-daily dosing, pharmacokinetic steady state is reached in approximately 5 days, with mean cumulative ratios of AUC, Cmax, and C24h ranging from 1.2 to 1.5. Plasma concentrations of dolutegravir increase disproportionately after doses exceeding 50 mg. Dolutegravir is a substrate of P-glycoprotein in vitro. The absolute bioavailability of dolutegravir has not been determined.

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Metabolism/Metabolites
Dolutegravir is primarily metabolized via three pathways, without forming long-acting metabolites. The first metabolic pathway is glucuronidation mediated by UGT1A1, the second is carbon oxidation mediated by CYP3A4, and the third appears to be a continuous process of oxidative defluorination and glutathione binding. The major metabolite in plasma is the ether glucuronide form (M2), whose chemical properties impair its ability to bind to metal ions, thus rendering it inactive. Dolutegravir is primarily metabolized via UGT1A1, with CYP3A also involved in some metabolism. ...dolutegravir ether glucuronide (18.9% of total dose), metabolites formed by benzylic carbon oxidation (3.0% of total dose), and their hydrolysis N-dealkylation products (3.6% of total dose). ...

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Biological half-life
The half-life of dolutegravir is 14 hours.
Based on population pharmacokinetic analysis, the terminal half-life of dolutegravir is approximately 14 hours, and the apparent clearance (CL/F) is 1.0 L/h.

Effects During Pregnancy and Lactation
◉ Overview of Drug Use During Lactation
Dolutegravir can be detected in small amounts in breast milk. Drug clearance from the newborn appears to be slow, and the drug can still be detected in the plasma of breastfed infants. Dolutegravir has been safely used in breastfeeding mothers of HIV-positive mothers and is recommended as a first-line treatment during lactation. Achieving and maintaining viral suppression through antiretroviral therapy can reduce the risk of breast milk transmission to below 1%, but not zero. For HIV-infected individuals receiving antiretroviral therapy with a persistently low viral load, their decision to breastfeed should be supported. If viral load is not suppressed, pasteurized donor breast milk or formula is recommended.
◉ Impact on Breastfed Infants
An HIV-positive mother takes a once-daily combination tablet (Triumeq) containing 50 mg dolutegravir, 600 mg abacavir sulfate, and 300 mg lamivudine. Her baby was exclusively breastfed for approximately 30 weeks, followed by partial breastfeeding for approximately 20 weeks. No significant side effects were observed. A study of HIV-infected women in Africa showed that during pregnancy and lactation, they received a dolutegravir-based treatment regimen, including dolutegravir 50 mg, tenofovir disoproxil fumarate 300 mg, and emtricitabine 200 mg in South Africa or lamivudine 300 mg in Uganda. For breastfed infants, this regimen was as safe as a regimen based on efavirenz containing the same other medications. In an open-label, controlled, multicenter phase 3 clinical trial, women diagnosed with HIV were randomly assigned to receive one of three regimens: dolutegravir, emtricitabine, and tenofovir disoproxil fumarate (n = 208); dolutegravir, emtricitabine, and tenofovir disoproxil fumarate (n = 202); or efavirenz, emtricitabine, and tenofovir disoproxil fumarate (n = 207). These regimens were initiated between 14 and 28 weeks of gestation and continued postpartum. Of the 617 live births, 99% were still breastfeeding at the time of their last HIV test, which was performed no later than 50 weeks of age. The mean duration of infant participation was 47.6 weeks. The proportion of infants experiencing grade 3 or higher clinical or laboratory adverse events ranged from 25% to 31%, but there was no statistically significant difference between groups. Compared with efavirenz, emtricitabine, and tenofovir disoproxil fumarate, dolutegravir-containing treatment regimens reduced virological failure rates, HIV resistance rates, and infant mortality within 50 weeks postpartum.
◉ Effects on Lactation and Breast Milk
As of the revision date, no relevant published information was found.

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Drug Interactions
Dolutegravir is primarily metabolized by UGT1A1, with CYP3A also involved. In vitro studies have shown that dolutegravir is also a substrate of UGT1A3, UGT1A9, BCRP, and P-gp. Drugs that induce these enzymes and transporters may decrease plasma concentrations of dolutegravir, thereby reducing its therapeutic effect. Concomitant use of dolutegravir with other drugs that inhibit these enzymes may increase plasma concentrations of dolutegravir. Etravirine can significantly reduce the plasma concentration of dolutegravir, but this effect of etravirine can be mitigated by the co-administration of lopinavir/ritonavir or darunavir/ritonavir, and it is expected that atazanavir/ritonavir will also mitigate this effect. Darunavir/ritonavir, lopinavir/ritonavir, rilpivirine, tenofovir, bosavirin, telaprevir, prednisone, rifabutin, and omeprazole have no clinically significant effect on the pharmacokinetics of dolutegravir.
Due to the potential for increased plasma concentrations of dofetride and the risk of serious and/or life-threatening events, the co-administration of TIVICAY with dofetride is contraindicated.

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Hepatotoxicity
In large clinical trials, 2% to 5% of patients treated with dolutegravir experienced alanine aminotransferase (ALT) elevations exceeding three times the upper limit of normal (ULN), but these rates were similar to those in matched controls receiving background-optimized antiretroviral therapy (without dolutegravir). These elevations were not clinically relevant and generally did not require dose adjustment. Several cases of acute liver injury with jaundice, associated with hypersensitivity reactions, have been described in dolutegravir registration trials and resolved upon discontinuation of the drug. Clinical characteristics of these cases were not provided, and their association with dolutegravir rather than concurrently used antiretroviral drugs was not fully established. However, since the approval and widespread use of dolutegravir, several cases of acute hepatitis caused by dolutegravir have been reported. The incubation period ranged from 1 to 8 months, and the pattern of serum enzyme elevation was hepatocellular. No immune hypersensitivity or autoimmune features were observed. At least one published case resulted in acute liver failure requiring liver transplantation. The dolutegravir product information label lists hepatitis and liver failure as potential adverse reactions, noting that patients with co-infection with hepatitis B or C virus may experience exacerbation or relapse of hepatitis due to immune reconstitution syndrome when starting dolutegravir treatment. Liver function monitoring is recommended for patients starting a dolutegravir-containing regimen. Probability score: D (may cause clinically significant liver damage).
Protein Binding
Dolutegravir is highly bound to human plasma proteins, reaching 98.9% of the administered dose.
Human Toxicity Excerpt
/Human Exposure Studies/ Dolutegravir is primarily metabolized and excreted by the liver. In a trial comparing 8 patients with moderate hepatic impairment (Child-Pugh B) and 8 matched healthy controls, the exposure after a single 50 mg dose of dolutegravir was similar in both groups. No dose adjustment is required for patients with mild to moderate hepatic impairment (Child-Pugh A or B). The effect of severe hepatic impairment (Child-Pugh C) on the pharmacokinetics of dolutegravir has not been investigated. Therefore, TIVICAY is not recommended for patients with severe hepatic impairment. National Institutes of Health; DailyMed. Latest information on the oral formulation of TIVICAY (dolutegravir sodium) film-coated tablets (first approved in the US: 2013). As of November 22, 2013, it is available at:
Excerpt of non-human toxicity/Experimental animals: Chronic exposure or carcinogenicity/A two-year carcinogenicity study of dolutegravir was conducted in mice and rats. Doses were administered up to 500 mg/kg in mice and up to 50 mg/kg in rats. In mice, no significant increase in drug-related tumor incidence was observed at the highest tested dose, resulting in an AUC exposure of approximately 14 times higher in mice than in humans at the recommended dose (50 mg twice daily). In rats, no increase in drug-related tumor incidence was observed at the highest tested dose, resulting in AUC exposures of dolutegravir in male and female rats that were 10-fold and 15-fold higher, respectively, than in humans at the recommended dose (50 mg twice daily).
/Experimental Animals: Developmental or Reproductive Toxicity/ In pregnant rabbits, oral administration of up to 1000 mg/kg/day of dolutegravir (approximately 0.4 times the AUC-based human clinical exposure of 50 mg twice daily) did not reveal developmental toxicity or teratogenicity. In rabbits, maternal toxicity (reduced food intake, scanty/absent feces/urine, inhibited weight gain) was observed at a dose of 1000 mg/kg. National Institutes of Health; DailyMed. Latest information on TIVICAY (dolutegravir sodium) tablets (film-coated) oral tablets (first approved in the US: 2013). As of November 22, 2013, information is available at the following URL:
/Experimental Animals: Developmental or Reproductive Toxicity/ Oral administration of up to 1000 mg/kg/day of dolutegravir to pregnant rats on days 6 to 17 of gestation, at a dose approximately 27 times the twice-daily human clinical exposure of 50 mg based on AUC, did not cause maternal toxicity, developmental toxicity, or teratogenicity. National Institutes of Health; DailyMed. Latest information on the use of TIVICAY (dolutegravir sodium) tablets (film-coated) oral tablets (first approved in the US: 2013). As of November 22, 2013, information is available at the following URL:
/Genetic Toxicity/ Dolutegravir did not show genotoxicity in bacterial reverse mutation assays, mouse lymphoma assays, or in vivo rodent micronucleus assays.

[1]. In Vitro antiretroviral properties of S/GSK1349572, a next-generation HIV integrase inhibitor. Antimicrob Agents Chemother. 2011 Feb;55(2):813-21.

[2]. Structural and functional analyses of the second-generation integrase strand transfer inhibitor dolutegravir (S/GSK1349572). Mol Pharmacol. 2011 Oct;80(4):565-72.

[3]. The comparative disposition and metabolism of dolutegravir, a potent HIV-1 integrase inhibitor, in mice, rats, and monkeys. Xenobiotica. 2015 Jan;45(1):60-70.

Dolutegravir sodium is an organic sodium salt, the monosodium salt of dolutegravir. It is used to treat HIV-1 infection. It is an HIV-1 integrase inhibitor. It contains dolutegravir (1-). Dolutegravir (brand names: Tivicay and Tivicay PD) is a prescription drug approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection and must be used in combination with the following medications: Adult patients using it in combination with other HIV medications; Children aged 4 weeks and older, weighing at least 3 kg (6.6 lbs), and meeting certain criteria (as determined by a healthcare provider) using it in combination with other HIV medications; or Adult patients using rilpivirine (brand name: Edurant) as a substitute for their current HIV medication when determined by a healthcare provider. Dolutegravir must be used in combination with other HIV medications.
Dolutegravir sodium is the sodium salt form of dolutegravir, an orally bioavailable integrase strand transfer inhibitor (INSTI) active against human immunodeficiency virus type 1 (HIV-1) infection. After oral administration, dolutegravir binds to the active site of integrase. Integrase is an enzyme in HIV that catalyzes the transfer of viral genetic material into human chromosomes. This prevents integrase from binding to retroviral deoxyribonucleic acid (DNA) and blocks the strand transfer step, which is essential for the HIV replication cycle. This prevents HIV-1 replication.
See also: Dolutegravir (with active fraction); Dolutegravir sodium; Lamivudine (component); Dolutegravir sodium; Rilpivirine hydrochloride (component).
Indications: Tivicay is indicated for use in combination with other antiretroviral drugs to treat adults, adolescents, and children aged 6 years and older with a weight of at least 14 kg infected with human immunodeficiency virus (HIV). Tivicay is indicated for use in combination with other antiretroviral drugs to treat adults, adolescents, and children at least 4 weeks of age and weighing at least 3 kg infected with human immunodeficiency virus (HIV).

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Therapeutic Use
HIV Integrase Inhibitor
For children aged 12 years and older and weighing at least 40 kg, the recommended dose of Tivicay is 50 mg orally once daily. If used in combination with efavirenz, fosanavir/ritonavir, tepranavir/ritonavir, or rifampin, the recommended dose of Tivicay is 50 mg twice daily. The safety and efficacy of TIVICAY in children under 12 years of age or weighing less than 40 kg, and in children who have previously received integrase inhibitor (INSTI) therapy and have demonstrated or clinically suspected resistance to other INSTIs (raltegravir, elvigravir), have not been established.
TIVICAY (dolutegravir) is indicated for use in combination with other antiretroviral agents to treat human immunodeficiency virus type 1 (HIV-1) infection in adults and children aged 12 years and older and weighing at least 40 kg. Before initiating TIVICAY treatment, the following should be considered: poor virological response has been observed in subjects receiving TIVICAY 50 mg twice daily who have the integrase strand transfer inhibitor (INSTI) resistance mutation Q148 and two or more other INSTI resistance mutations (including L74I/M, E138A/D/K/T, G140A/S, Y143H/R, E157Q, G163E/K/Q/R/S, or G193E/R).
Dolutegravir is less frequently cleared by the kidneys. In a trial comparing eight patients with severe renal impairment (creatinine clearance <30 mL/min) with eight matched healthy controls, dolutegravir showed reductions in AUC, Cmax, and C24 of 40%, 23%, and 43%, respectively, compared to matched healthy subjects. The reason for this reduction is unclear. Population pharmacokinetic analyses using data from the SAILING and VIKING-3 trials indicated that mild to moderate renal impairment had no clinically relevant effect on dolutegravir exposure. No dose adjustment is required for treatment-naïve or treatment-naïve patients with mild, moderate, or severe renal impairment who have not received integrase inhibitor (INSTI) therapy, or for patients who have received INSTI therapy and have mild or moderate renal impairment (carrying certain INSTI-related resistance mutations or clinically suspected INSTI resistance). In patients who have received INSTI treatment and have severe renal impairment (carrying certain INSTI-related resistance mutations or clinically suspected INSTI resistance [see Microbiology (12.4)]), caution should be exercised when using dolutegravir, as a decrease in dolutegravir concentration may lead to loss of efficacy and may introduce resistance to TIVICAY or other antiretroviral agents used in combination. Dolutegravir has not been studied in patients requiring dialysis. Dolutegravir is primarily metabolized and excreted in the liver. In a trial comparing 8 patients with moderate hepatic impairment (Child-Pugh Class B) and 8 matched healthy controls, drug exposure after a single 50 mg dose of dolutegravir was similar in both groups. No dose adjustment is required for patients with mild to moderate hepatic impairment (Child-Pugh Class A or B). The effect of severe hepatic impairment (Child-Pugh Class C) on the pharmacokinetics of dolutegravir has not been studied. Therefore, TIVICAY is not recommended for patients with severe hepatic impairment.

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Drug Warning
The U.S. Centers for Disease Control and Prevention (CDC) recommends that mothers in the United States infected with HIV-1 do not breastfeed their infants to avoid the risk of postpartum transmission of HIV-1 infection. Studies on lactating rats and their offspring have shown the presence of dolutegravir in rat milk. It is currently unknown whether dolutegravir is excreted into human milk. Due to the potential for HIV transmission and the risk of adverse reactions in nursing infants, mothers receiving TIVICAY should be advised against breastfeeding.
Pregnancy category B. There are currently no adequate and well-controlled studies in pregnant women. Because results from animal reproductive studies do not always predict human responses, and animal studies have shown that dolutegravir can cross the placenta, this drug should only be used during pregnancy if clearly needed.
Dolutegravir (TIVICAY) should not be used alone with etravirine, but should be taken concurrently with atazanavir/ritonavir, darunavir/ritonavir, or lopinavir/ritonavir.
Immune reconstitution syndrome has been reported in patients receiving combination antiretroviral therapy, including TIVICAY. In the initial phase of combination antiretroviral therapy, patients with a responsive immune system may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus infection, Pneumocystis carinii pneumonia (PCP), or tuberculosis), which may require further evaluation and treatment. Autoimmune diseases (such as Graves' disease, polymyositis, and Guillain-Barré syndrome) have also been reported in the case of immune reconstitution; however, the onset time is more unpredictable and may occur several months after the start of treatment.
For more complete data on dolutegravir (of 8), please visit the HSDB record page.

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Pharmacodynamics
HIV-1 infected patients receiving dolutegravir monotherapy exhibited rapid and dose-dependent decreases in antiviral activity, along with a decrease in HIV-1 RNA copy number per milliliter. The antiviral response lasted 3 to 4 days after the last dose. Sustained responses obtained in clinical trials indicate that dolutegravir has a tight binding and long dissociation half-life, giving it a high resistance barrier. The combination therapy (rilpivirine and dolutegravir) demonstrated the same viral suppression as previous three-drug therapies, without integrase strand transfer inhibitor mutations or rilpivirine resistance. Dolutegravir is a monocarboxylic acid amide, formed by the condensation of the carboxyl group of (4R,12aS)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1',2':4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxylic acid with the amino group of 2,4-difluorobenzylamine. (In its sodium salt form) it is used to treat HIV-1 infection. It is an HIV-1 integrase inhibitor. It is a monocarboxylic acid amide, an organic heterocyclic compound, a secondary carboxamide, and difluorobenzene. It is the conjugate acid of dolutegravir (1-). Dolutegravir (brand names: Tivicay and Tivicay PD) is a prescription drug approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection and must be used in combination with the following medications: Adult patients using it in combination with other HIV medications; Children aged 4 weeks and older, weighing at least 3 kg (6.6 lbs), and meeting certain criteria (as determined by a healthcare provider) using it in combination with other HIV medications; or Adult patients using rilpivirine (brand name: Edurant) as a substitute for their current HIV medication when determined by a healthcare provider. Dolutegravir must be used in combination with other HIV medications. Dolutegravir is an HIV-1 integrase inhibitor that blocks the chain transfer step (INSTI) in which the viral genome integrates into host cells. The drug's mechanism of action is independent of human host cells, therefore it is well-tolerated and has very low toxicity. Dolutegravir was developed by ViiV Healthcare and approved by the FDA on August 12, 2013. On November 21, 2017, dolutegravir, in combination with rilpivirine, was approved as part of Juluca, the first complete two-drug regimen, for the treatment of HIV-1 infection in adults. Dolutegravir is a human immunodeficiency virus integrase chain transfer inhibitor. Its mechanism of action includes inhibition of HIV integrase, multidrug and toxin efflux transporter 1 (MTET1), and organic cation transporter 2 (OCT2). Dolutegravir is a human immunodeficiency virus (HIV) integrase inhibitor and the third drug in this class to target viral integrase. Dolutegravir is only used in combination with other antiretroviral drugs to treat HIV infection, and its application is limited. The incidence of elevated serum transaminases during dolutegravir treatment is low, but no cases of acute, clinically significant liver injury have been found.
Dolutegravir is an orally bioavailable integrase strand transfer inhibitor (INSTI) effective against human immunodeficiency virus type 1 (HIV-1) infection. After oral administration, dolutegravir binds to the active site of integrase. Integrase is an enzyme in HIV that catalyzes the transfer of viral genetic material into the human chromosome. This prevents the integrase from binding to the retroviral deoxyribonucleic acid (DNA) and blocks the strand transfer step, which is essential for the HIV replication cycle. This prevents HIV-1 replication.
Dolutegravir is a small molecule drug, with clinical trials up to Phase IV (covering all indications). It was first approved in 2013 for HIV and HIV-1 infection and has seven investigational indications.

C20H18F2N3NAO5

441.36

441.111

C, 54.43; H, 4.11; F, 8.61; N, 9.52; Na, 5.21; O, 18.12

1051375-19-9

Dolutegravir;1051375-16-6; 1051375-16-6 (free); 1051375-19-9 (sodium); 1357289-29-2 (RR-isomer); 1309560-49-3 (SR isomer)

46216142

Off-white to yellow solid powder

2.303

1

8

3

31

836

2

C[C@@H]1CCO[C@@H]2N1C(=O)C3=C(C(=O)C(=CN3C2)C(=O)NCC4=C(C=C(C=C4)F)F)[O-].[Na+]

UGWJRRXTMKRYNK-VSLILLSYSA-M

InChI=1S/C20H19F2N3O5.Na/c1-10-4-5-30-15-9-24-8-13(17(26)18(27)16(24)20(29)25(10)15)19(28)23-7-11-2-3-12(21)6-14(11)22;/h2-3,6,8,10,15,27H,4-5,7,9H2,1H3,(H,23,28);/q;+1/p-1/t10-,15+;/m1./s1

sodium;(3S,7R)-13-[(2,4-difluorophenyl)methylcarbamoyl]-7-methyl-9,12-dioxo-4-oxa-1,8-diazatricyclo[8.4.0.03,8]tetradeca-10,13-dien-11-olate

DOLUTEGRAVIR SODIUM; 1051375-19-9; Tivicay; Dolutegravir sodium salt; GSK 1349572A;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ≥ 4.5 mg/mL (10.20 mM)
H2O : < 0.1 mg/mL

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)