With an IC50 of 3.0 nM, capetreavir (GSK-1265744) blocks the strand transfer reaction that HIV-1 integrase catalyzes in vitro. In PBMCs, the antiviral EC50 against NL432 and HIV-1 Ba-L was 0.34 nM and 0.22 nM, respectively. The EC50 in MT-4 cells was found to be 0.57 nM using CellTiter-Glo, 1.3 nM using MTT, and 0.5 nM in the pseudotyped self-inactivating virus (PHIV) test [3].

In mice, capetreavir can have a half-life of up to 54 days [1]. When macaques (Macaques) are infected with SIVmac251, they are protected by capetregravir (iv; single dose or twice; 25 or 50 mg/kg) [4].

Cell Viability Assay[3]
Cell Types: MT-4 cells
Tested Concentrations: 0-32 nM
Incubation Duration: 4 or 5 days
Experimental Results: demonstrated antiviral activity with an EC50 of 1.3 nM.

Absorption, Distribution and Excretion
Oral cabotegravir has a Tmax of 3 hours, reaches a Cmax of 8.0 µg/mL, and has an AUC of 145 µg\*h/mL. Intramuscular extended-release cabotegravir has a Tmax of 7 days, reaches a Cmax of 8.0 µg/mL, and has an AUC of 1591 µg\*h/mL.
An oral radiolabelled dose of cabotegravir is 58.5% recovered in the feces and 26.8% recovered in the urine.
Data regarding the volume of distribution of cabotegravir is not readily available.
Data regarding the clearance of cabotegravir is not readily available. Clearance in dogs was 0.34 mL/min/kg and in cynomolgus monkeys was 0.32 mL/min/kg.

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Metabolism / Metabolites
Cabotegravir is O-glucuronidated to the M1 and M2 metabolites, with 67% of glucuronidation performed by UGT1A1, and 33% by UGT1A9.

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Biological Half-Life
The mean half life of oral cabotegravir is 41 hours. The mean half life of intramuscular extended-release cabotegravir is 5.6-11.5 weeks.

Hepatotoxicity
In large clinical trials, switching antiretroviral therapy of HIV infection to the combination of parenteral injections of long acting cabotegravir and rilpivirine was associated with alanine aminotransferase (ALT) elevations in up to 7% of patients, but levels above 5 times the upper limit of normal (ULN) arose in only 1% to 2% of subjects. The elevations were typically transient, asymptomatic, and rarely required dose modification or discontinuation. While clinically apparent liver injury with jaundice was reported to occur in early studies, there were no such cases in the large, preregistration trials of long acting, parenteral cabotegravir and rilpivirine used for treatment of HIV infection or in the large trials of long acting cabotegravir used as prophylaxis against acquiring HIV infection. The use of injections every 4 or 8 weeks has been found to improve compliance and to be preferable to daily oral therapy by many patients requiring long term antiretroviral therapy. Since approval of cabotegravir for use as maintenance therapy and for prophylaxis against HIV infection, there have been no case reports of clinically apparent hepatotoxicity associated with its use.
Interestingly, in the large preregistration trials of parenteral cabotegravir and rilpivirine as replacement therapy of HIV infection, cases of acute hepatitis A, B and C were reported as adverse events, occurring largely in patients who had been switched to the parenteral regimen compared to control subjects who were continued on oral agents. The reasons for these differences were unclear. Importantly, neither cabotegravir or rilpivirine have activity against hepatitis B virus (HBV), and one possibility has been that reactivation of hepatitis B may occur after withdrawal of oral antiretroviral agents that have activity against HBV, such as tenofovir, emtricitabine, and lamivudine. For this reason, patients starting long- acting parenteral regimens of cabotegravir and rilpivirine should be screened for hepatitis B virus markers and potential risks of stopping agents with activity against HBV should be considered. In addition, persons with HIV without protective antibodies to HAV and HBV should be offered hepatitis A and B virus vaccination.
Likelihood score: E* (unproven but suspected cause of clinically apparent liver injury).

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Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No published information is available on the use of cabotegravir during breastfeeding. Achieving and maintaining viral suppression with antiretroviral therapy decreases breastfeeding transmission risk to less than 1%, but not zero. Individuals with HIV who are on antiretroviral therapy with a sustained undetectable viral load and who choose to breastfeed should be supported in this decision. If a viral load is not suppressed, banked pasteurized donor milk or formula is recommended.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
Cabotegravir is >99.8% bound to proteins in plasma, usually alubmin.

[1]. Zhou T, et al. Creation of a nanoformulated cabotegravir prodrug with improved antiretroviral profiles. Biomaterials. 2018 Jan;151:53-65.
[2]. Reese MJ, et al. Drug interaction profile of the HIV integrase inhibitor cabotegravir: assessment from in vitro studies and a clinical investigation with midazolam. Xenobiotica. 2015 Sep 4:1-12.
[3]. Yoshinaga T, et al. Antiviral characteristics of GSK1265744, an HIV integrase inhibitor dosed orally or by long-acting injection. Antimicrob Agents Chemother. 2015 Jan;59(1):397-406.
[4]. Andrews CD, et al. Cabotegravir long acting injection protects macaques against intravenous challenge with SIVmac251. AIDS. 2017 Feb 20;31(4):461-467.

Pharmacodynamics
Cabotegravir is an inhibitor of HIV integrase, which reduces viral replication. It has a long duration of action as the oral tablet is given daily and the intramuscular suspension is given monthly. Patients should be counselled regarding the risk of hypersensitivity, hepatotoxicity, and depression.

C19H17F2N3O5

405.35

405.113

C, 56.30; H, 4.23; F, 9.37; N, 10.37; O, 19.73

1051375-10-0

Dolutegravir;1051375-16-6;Cabotegravir sodium;1051375-13-3;Cabotegravir-d5;2750534-77-9

54713659

Solid powder

1.6±0.1 g/cm3

664.0±55.0 °C at 760 mmHg

355.4±31.5 °C

0.0±2.1 mmHg at 25°C

1.661

-1.7

2

8

3

29

814

2

C[C@H]1CO[C@H]2N1C(=O)C3=C(C(=O)C(=CN3C2)C(=O)NCC4=C(C=C(C=C4)F)F)O

WCWSTNLSLKSJPK-LKFCYVNXSA-N

InChI=1S/C19H17F2N3O5/c1-9-8-29-14-7-23-6-12(16(25)17(26)15(23)19(28)24(9)14)18(27)22-5-10-2-3-11(20)4-13(10)21/h2-4,6,9,14,26H,5,7-8H2,1H3,(H,22,27)/t9-,14+/m0/s1

(3S,11aR)-N-(2,4-difluorobenzyl)-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydrooxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide

GSK744; S/GSK 1265744; GSK-744; S/GSK1265744; GSK 744; S/GSK-1265744; Cabotegravir; Cabenuva.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

Solubility in Formulation 1: ≥ 1.67 mg/mL (4.12 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 16.7 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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