HCV NS3/4A protease(IC50: 3.5~11.3 nM)

Glecaprevir (formerly ABT-493) is a novel hepatitis C virus (HCV) NS3/4A protease inhibitor (PI) with pangenotypic activity. It inhibited the enzymatic activity of purified NS3/4A proteases from HCV genotypes 1 to 6 in vitro (half-maximal [50%] inhibitory concentration = 3.5 to 11.3 nM) and the replication of stable HCV subgenomic replicons containing proteases from genotypes 1 to 6 (50% effective concentration [EC50] = 0.21 to 4.6 nM). Glecaprevir had a median EC50 of 0.30 nM (range, 0.05 to 3.8 nM) for HCV replicons containing proteases from 40 samples from patients infected with HCV genotypes 1 to 5. Importantly, glecaprevir was active against the protease from genotype 3, the most-difficult-to-treat HCV genotype, in both enzymatic and replicon assays demonstrating comparable activity against the other HCV genotypes. In drug-resistant colony selection studies, glecaprevir generally selected substitutions at NS3 amino acid position A156 in replicons containing proteases from genotypes 1a, 1b, 2a, 2b, 3a, and 4a and substitutions at position D/Q168 in replicons containing proteases from genotypes 3a, 5a, and 6a. Although the substitutions A156T and A156V in NS3 of genotype 1 reduced susceptibility to glecaprevir, replicons with these substitutions demonstrated a low replication efficiency in vitro Glecaprevir is active against HCV with most of the common NS3 amino acid substitutions that are associated with reduced susceptibility to other currently approved HCV PIs, including those at positions 155 and 168. Combination of glecaprevir with HCV inhibitors with other mechanisms of action resulted in additive or synergistic antiviral activity. In summary, glecaprevir is a next-generation HCV PI with potent pangenotypic activity and a high barrier to the development of resistance.

Glecaprevir inhibited the enzymatic activity of HCV genotype 1 to 6 NS3/4A proteases, with the half-maximal (50%) inhibitory concentration (IC50) values ranging from 3.5 to 11.3 nM in a biochemical assay. When glecaprevir was tested against six human serine proteases (chymase, chymotrypsin type II, chymotrypsin type VII, elastase, kallikrein, and urokinase) and one human cysteine protease (cathepsin B), no inhibition was observed at concentrations up to 200,000 nM. These results indicate that glecaprevir demonstrates a high level of selectivity for the HCV NS3/4A protease over the human proteases tested.

HCV subgenomic replicon cells containing the protease from genotype 1a, 1b, 2a, 2b, 3a, 4a, 5a, or 6a were passaged in the presence of glecaprevir at concentrations 10- or 100-fold its EC50s for the respective replicon cell lines to select for colonies with substitutions that conferred resistance to glecaprevir. Glecaprevir generally selected a low number of colonies containing resistance-conferring substitutions in replicon cells across the different HCV genotypes. Higher colony counts were observed with selections using replicons with the genotype 2a JFH-1 backbone (i.e., the genotype 2a and 2b replicons in this study), regardless of the selection concentrations. This was likely due to the exceptionally high replication rates for replicons with this backbone.

Absorption, Distribution and Excretion
In healthy subjects, the time it takes to reach the peak plasma concentration (Tmax) is approximately 5 hours. The mean peak plasma concentration (Cmax) is 597ng/mL in non-cirrhotic HCV-infected subjects. Relative to fasting conditions, the consumption of meals increases the absorption of glecaprevir by 83-163%.
The predominant route of elimination of the drug is biliary-fecal, where 92.1% of administered drug is excreted in feces and 0.7% of the drug is excreted in the urine.

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Metabolism / Metabolites
Glecaprevir undergoes limited secondary metabolism in vitro, predominantly by CYP3A.

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Biological Half-Life
The elimination half life (t1/2) is approximately 6 hours.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Glecaprevir has not been studied in nursing mothers being treated for hepatitis C infection. Because it is 97.5% bound to maternal plasma proteins, amounts in breastmilk are likely to be very low.
Hepatitis C is not transmitted through breastmilk and breastmilk has been shown to inactivate hepatitis C virus (HCV). However, the Centers for Disease Control recommends that mothers with HCV infection should consider abstaining from breastfeeding if their nipples are cracked or bleeding. It is not clear if this warning would apply to mothers who are being treated for hepatitis C.
Infants born to mothers with HCV infection should be tested for HCV infection; because maternal antibody is present for the first 18 months of life and before the infant mounts an immunologic response, nucleic acid testing 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
Pibrentasvir is 97.5% bound to human plasma proteins. The Blood-to-plasma ratio is approximately 0.57.

[1]. Antimicrob Agents Chemother.2017;62(1). pii: e01620-17.

[2]. Antimicrob Agents Chemother.2015;60(3):1546-55.

[3]. Signal Transduct Target Ther. 2021 May 29;6(1):212.

Glecaprevir is a direct acting antiviral agent and Hepatitis C virus (HCV) NS3/4A protease inhibitor that targets the the viral RNA replication. In combination with [DB13878], glecaprevir is a useful therapy for patients who experienced therapeutic failure from other NS3/4A protease inhibitors. It demonstrates a high genetic barrier against resistance mutations of the virus. In cell cultures, the emergence of amino acid substitutions at NS3 resistance-associated positions A156 or D/Q168 in HCV genotype 1a, 2a or 3a replicons led to reduced susceptibility to glecaprevir. The combinations of amino acid substitutions at NS3 position Y65H and D/Q168 also results in greater reductions in glecaprevir susceptibility, and NS3 Q80R in genotype 3a patients also leads to glecaprevir resistance. Glecaprevir is available as an oral combination therapy with [DB13878] under the brand name Mavyret. This fixed-dose combination therapy was FDA-approved in August 2017 to treat adults with chronic hepatitis C virus (HCV) genotypes 1-6 without cirrhosis (liver disease) or with mild cirrhosis, including patients with moderate to severe kidney disease and those who are on dialysis. Mavyret is also indicated for HCV genotype 1-infected patients who have been previously treated with regimens either containing an NS5A inhibitor or an NS3/4A protease inhibitor, but not both. Hepatitis C viral infection often leads to decreased liver function and subsequent liver failure, causing a significantly negative impact on the patients' quality of life. The ultimate goal of the combination treatment is to achieve sustained virologic response (SVR) and cure the patients from the infection. In clinical trials, this combination therapy achieved SVR12 rate, or undetectable Hepatitis C for twelve or more weeks after the end of treatment, of ≥93% across genotypes 1a, 2a, 3a, 4, 5 and 6.
Glecaprevir is a Hepatitis C Virus NS3/4A Protease Inhibitor. The mechanism of action of glecaprevir is as a HCV NS3/4A Protease Inhibitor, and P-Glycoprotein Inhibitor, and Breast Cancer Resistance Protein Inhibitor, and Organic Anion Transporting Polypeptide 1B1 Inhibitor, and Organic Anion Transporting Polypeptide 1B3 Inhibitor, and Cytochrome P450 3A Inhibitor, and Cytochrome P450 1A2 Inhibitor, and UGT1A1 Inhibitor.

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Drug Indication
Indicated for the treatment of adult patients with chronic hepatitis C virus (HCV) genotype 1, 2, 3, 4, 5 or 6 infection without cirrhosis or with compensated cirrhosis (Child-Pugh A). MAVYRET is also indicated for the treatment of adult patients with HCV genotype 1 infection, who previously have been treated with a regimen containing an HCV NS5A inhibitor or an NS3/4A protease inhibitor (PI), but not both.
FDA Label
Maviret is indicated for the treatment of chronic hepatitis C virus (HCV) infection in adults and children aged 3 years and older. Maviret coated granules is indicated for the treatment of chronic hepatitis C virus (HCV) infection in children 3 years and older.

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Mechanism of Action
Glecaprevir is an inhibitor of the HCV NS3/4A protease, which is a viral enzyme necessary for the proteolytic cleavage of the HCV encoded polyprotein into mature forms of the NS3, NS4A, NS4B, NS5A, and NS5B proteins. These multifunctional proteins, including NS3, are essential for viral replication. The N-terminal of NS3 protein confers serine protease activity, whileThe C-terminus of NS3 encodes a DExH/D-box RNA helicase which hydyolyzes NTP as an energy source to unwind double-stranded RNA in a 3′ to 5′ direction during replication of viral genomic RNA. NS4A is a cofactor for NS3 that directs the localization of NS3 and modulates its enzymatic activities. Glecaprevir disrupts the intracellular processes of the viral life cycle through inhibiting the NS3/4A protease activity of cleaving downstream junctions of HCV polypeptide and proteolytic processing of mature structural proteins.

C38H46F4N6O9S

838.87

838.298

C, 54.41; H, 5.53; F, 9.06; N, 10.02; O, 17.16; S, 3.82

1365970-03-1

1365970-03-1 (free);1838572-01-2 (hydrate);

66828839

White to off-white solid powder

1.5±0.1 g/cm3

1.610

1.71

3

15

7

58

1760

7

S(C1(C)CC1)(NC([C@]1(C[C@H]1C(F)F)NC([C@@H]1C[C@@H]2CN1C([C@H](C(C)(C)C)NC(=O)O[C@@H]1CCC[C@H]1OCC=CC(C1C(=NC3C=CC=CC=3N=1)O2)(F)F)=O)=O)=O)(=O)=O |c:41|

MLSQGNCUYAMAHD-ITNVBOSISA-N

InChI=1S/C38H46F4N6O9S/c1-35(2,3)28-32(50)48-19-20(17-24(48)30(49)46-37(18-21(37)29(39)40)33(51)47-58(53,54)36(4)14-15-36)56-31-27(43-22-9-5-6-10-23(22)44-31)38(41,42)13-8-16-55-25-11-7-12-26(25)57-34(52)45-28/h5-6,8-10,13,20-21,24-26,28-29H,7,11-12,14-19H2,1-4H3,(H,45,52)(H,46,49)(H,47,51)/b13-8+/t20-,21+,24+,25-,26-,28-,37-/m1/s1

(3aR,7S,10S,12R,21E,24aR)-7-tert-butyl-N-{(1R,2R)-2(difluoromethyl)-1-[(1-methylcyclopropane-1-sulfonyl)carbamoyl]cyclopropyl}-20,20-difluoro5,8-dioxo-2,3,3a,5,6,7,8,11,12,20,23,24a-dodecahydro-1H,10H-9,12methanocyclopenta[18,19][1,10,17,3,6]trioxadiazacyclononadecino[11,12-b]quinoxaline-10carboxamide

ABT-493; ABT493; ABT 493; A-1282576; A 1282576; A1282576; A-1282576.0; Glecaprevir; MAVYRET.

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)

DMSO : 83.3 ~100 mg/mL ( 99.30 ~119.2 mM )
Ethanol : ~100 mg/mL

Solubility in Formulation 1: ≥ 2.08 mg/mL (2.48 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (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 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (2.48 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 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 3: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.08 mg/mL (2.48 mM)

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