Exportin 1 (XPO1/CRM1) [1]
Verdinexor targets the nuclear export protein Exportin 1 (XPO1/CRM1). It acts as a selective inhibitor of nuclear export (SINE). By inhibiting XPO1, it prevents the nuclear export of tumor suppressor proteins and other growth-regulatory proteins, leading to their accumulation in the nucleus and the induction of apoptosis in cancer cells. It also has antiviral activity, inhibiting influenza virus replication. Its IC50 values for Jurkat and canine DLBCL cells are 8.7 nM and 13.3 nM, respectively.

Verdinexor inhibits the viability of Jurkat, OCI-Ly3, OCI-Ly10, and CLBL1 cells with IC50 of 0.3 nM, 2.1 nM, 41.8 nM, and 8.5 nM, respectively. KPT-335 also induces apoptosis in CLBL1 cells and primary canine DLBCL cells that express XPO1 and SINE. Verdinexor potently and selectively inhibits vRNP export and effectively inhibits the replication of various influenza virus A and B strains, including pandemic H1N1 virus, highly pathogenic H5N1 avian influenza virus, and the recently emerged H7N9 strain.
Cell Assay: Cell viability for lymphoid lines is determined by the MTS assay using CellTiter 96® AQueous One Solution Cell Proliferation Assay Kit. Briefly, for lymphoid cell lines, 5×104 cells (or 1×105 primary DLBCL cells) are cultured in 100 µL of complete medium in 96-well plates in the presence of SINE compounds. After 72 hours, 20 µL of MTS solution is added to each well and cells are incubated for another 4 hours before measuring absorbance at 490 nm using a Wallac Victor 1420 Multilabel Counter. The IC50 of SINE is calculated using Prism 6 software. For the non-lymphoid cell lines, 96 well plates are seeded in triplicate in 90 µL with 2500 cells/well of OSA16, 5000 cells/well of C2, and 2500 cells/well of 323610-3. Seeded plates are cultured overnight then treated the following day with 10 µL of KPT-214 in C10 media at concentrations of 0.0001, 0.01, 0.1, 1.0, and 10 µM. Plates are collected at 92 hours, centrifuged at 1300 rpm, and supernatant is removed by inverting plates on absorbent paper. Plates are then sealed and immediately placed at −80°C for a minimum of 12 hours. Plates are then thawed and CyQUANT ®Cell Proliferation Assay is performed following the manufacturer’s protocol. Briefly, 200 µL of the diluted working CyQUANT solution is added to each well and protected from light. Fluorescence is the measured using a SpectraMax M2 microplate reader at 480 nm excitation and 520 nm emission. Results are represented as percent of control, or plotted to calculate IC50 values at 92 hours.

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In vitro, Verdinexor inhibits the viability of Jurkat and canine DLBCL cells with IC50 values of 8.7 nM and 13.3 nM, respectively. It effectively inhibits the replication of influenza A and B virus strains in A549 cells. These in vitro studies confirm its mechanism as a selective inhibitor of nuclear export and its potential as an anticancer and antiviral agent. It is a valuable tool for studying XPO1 biology.

Verdinexor (KPT-335) is potent in inhibiting virus shedding, moderating leukocyte infiltration into the bronchoalveolar space, and reducing pulmonary pro-inflammatory cytokine expression in mice.
In vivo, intraperitoneal administration of KPT-335 at 5 mg/kg biweekly for 2 weeks significantly reduced the total kidney weight/body weight ratio in Pkd1v/v mice (control n=7, KPT-335 n=5) [1].
Immunohistochemistry showed a clear reduction in the proliferation marker Ki-67 in treated kidneys versus controls, indicating inhibition of proliferation [1].
Confirmation of on-target effects: p53 showed clear confinement within the nuclei of tubular epithelial cells in the treatment group [1].
In vivo, Verdinexor is an orally bioavailable compound. It has been investigated in clinical trials for safety and tolerability. Its antiviral activity has been demonstrated in preclinical models. As an XPO1 inhibitor, it has the potential for the treatment of cancer and viral infections. However, specific detailed in vivo study results are not extensively documented in standard summaries.

Non-cellular assays for Verdinexor typically involve measuring its binding to XPO1/CRM1. These assays may use purified XPO1 and measure the displacement of a labeled ligand or the inhibition of its interaction with nuclear export signals. Its selectivity for XPO1 over other proteins can be assessed. These experiments are essential for characterizing its binding properties.

In vitro cell-based assays for Verdinexor are conducted using cancer cell lines, such as Jurkat or DLBCL cells, to assess its effects on cell viability and apoptosis. Cells are treated with the compound, and cell viability is measured using MTT or similar assays. The accumulation of nuclear proteins can be assessed by immunofluorescence or Western blotting. Its antiviral activity can be assessed in virus-infected cells. These experiments are crucial for confirming its mechanism of action.

20 mg/kg every two days; Oral gavage BALB/c female mice (6-8 week-old)

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Pkd1v homozygous mice (mutation disrupting the G protein-coupled receptor proteolytic site cleavage site encoded in PKD1) were used. Pkd1v pups were treated with KPT-335 or vehicle by intraperitoneal injection biweekly starting at postnatal days 3 and 4 (P3 and P4). The pups received a weight-adjusted dosage of 5 mg/kg or a matching volume of vehicle. At 2 weeks of age, pups were euthanized and kidneys collected for assessment (kidney weight/body weight ratio) and staining [1].
In vivo animal studies for Verdinexor are typically conducted in mouse models of cancer or viral infection to evaluate its efficacy. Tumor-bearing or virus-infected mice are treated with the compound, and tumor growth or viral load is monitored. However, specific detailed protocols are not extensively documented in standard summaries. Its efficacy in preclinical models supports its potential as a therapeutic agent.

Verdinexor has a molecular weight of 442.32 g/mol and a molecular formula of C18H12F6N6O. It is an orally bioavailable compound. As a research compound, its pharmacokinetic properties have been studied in preclinical models and clinical trials. It is typically administered orally. Its half-life and other pharmacokinetic parameters are available from clinical studies.

The safety profile of Verdinexor has been evaluated in clinical trials. Common side effects may include gastrointestinal disturbances, fatigue, and myelosuppression. As with all investigational drugs, it carries risks of adverse effects. Comprehensive toxicological data are available from its clinical development program. Verdinexor is not an approved drug and is available as a research compound.

J Virol.2014 Sep 1;88(17):10228-43;Am J Physiol Renal Physiol.2014 Dec 1;307(11):F1179-86.

Kpt 335 is being studied in the clinical trial NCT02431364 (Safety and tolerability trial of oral Verdinexor (Verdinexor) in healthy adults).

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KPT-335 is a parallel inhibitor to KPT-330 (which is orally bioavailable and in phase 1 trials for cancers). The mechanism of action for XPO1 inhibition in ADPKD involves G0/G1 cell cycle arrest via downregulation of CDK4, mediated by nuclear confinement of C/EBPβ and subsequent upregulation of C/EBPα (though this mechanism was demonstrated with KPT-330 and KPT-251, not directly with KPT-335) [1].
Verdinexor (KPT-335) is an orally bioavailable, selective inhibitor of nuclear export (SINE) that inhibits XPO1/CRM1. It inhibits the viability of Jurkat and canine DLBCL cells with IC50 values of 8.7 nM and 13.3 nM, respectively. It also has antiviral activity against influenza viruses. Verdinexor is not an approved drug and is available as a research compound for studying XPO1 biology and cancer.

C18H12F6N6O

442.32

442.097

C, 48.88; H, 2.73; F, 25.77; N, 19.00; O, 3.62

1392136-43-4

71492799

Light yellow to yellow solid powder

1.5±0.1 g/cm3

1.577

4.1

2

11

5

31

620

0

O=C(NNC1=NC=CC=C1)/C=C\N2N=C(C3=CC(C(F)(F)F)=CC(C(F)(F)F)=C3)N=C2

OPAKEJZFFCECPN-XQRVVYSFSA-N

InChI=1S/C18H12F6N6O/c19-17(20,21)12-7-11(8-13(9-12)18(22,23)24)16-26-10-30(29-16)6-4-15(31)28-27-14-3-1-2-5-25-14/h1-10H,(H,25,27)(H,28,31)/b6-4-

(Z)-3-[3-[3,5-bis(trifluoromethyl)phenyl]-1,2,4-triazol-1-yl]-N'-pyridin-2-ylprop-2-enehydrazide

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: ≥ 2.5 mg/mL (5.65 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 25.0 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: ≥ 2.5 mg/mL (5.65 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 25.0 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.)