Pacritinib (SB1518)

Alias: Pacritinib; SB-1518; Vonjo; SB1518; SB 1518
Cat No.:V0331 Purity: ≥98%
Pacritinib (formerly also known as SB-1518;SB1518; trade name Vonjo)is a novel, potent, selective, andorally bioavailable inhibitor of Janus Kinase 2 (JAK2) and Fms-Like Tyrosine Kinase-3 (FLT3) with potential antitumor activity.
Pacritinib (SB1518) Chemical Structure CAS No.: 937272-79-2
Product category: JAK
This product is for research use only, not for human use. We do not sell to patients.
Size Price Stock Qty
2mg
5mg
10mg
25mg
50mg
100mg
250mg
Other Sizes

Other Forms of Pacritinib (SB1518):

  • Pacritinib HCl
Official Supplier of:
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Alternate Text
Top Publications Citing lnvivochem Products
Purity & Quality Control Documentation

Purity: ≥98%

Product Description

Pacritinib (formerly also known as SB-1518; SB1518; trade name Vonjo) is a novel, potent, selective, and orally bioavailable inhibitor of Janus Kinase 2 (JAK2) and Fms-Like Tyrosine Kinase-3 (FLT3) with potential antitumor activity. As of Feb 2022, the US FDA has approved pacritinib for the treatment of patients with myelofibrosis and severe thrombocytopenia. It inhibits JAK2 and FLT3 with IC50s of 23 and 22 nM in cell-free assays, respectively. Pacritinib also inhibits FLT3D835Y (FLT3's mutant form) with an IC50 of 6 nM. Pacritinib competes with JAK2 for ATP binding, which may result in inhibition of JAK2 activation, inhibition of the JAK-STAT signaling pathway, and so caspase-dependent apoptosis. JAK2 is the most common mutated gene in bcr-abl-negative myeloproliferative disorders.

Biological Activity I Assay Protocols (From Reference)
ln Vitro
Pacritinib (SB1518) has two times the potency against TYK2 (IC50=50 nM), 23 times the potency against JAK3 (IC50=520 nM), and 56 times the potency against JAK1 (IC50=1280 nM) in comparison to JAK2. When tested against 100 nM Pacritinib at adenosine triphosphate comparable concentrations to its Michaelis constant (Km), the remaining assessed kinases exhibit <30% inhibition. With an IC50 of 47 and 67 nM, respectively, paritinib inhibits MV4-11 and MOLM-13 cells, which are cell lines generated from human acute myeloid leukemias caused by a FLT3 ITD mutation. The JAK2 signaling-dependent cell lines Karpas 1106P and Ba/F3-JAK2V617F are inhibited by paritinib with IC50 values of 348 and 160 nM, respectively. accordingly[1]. MV4-11 cells bearing FLT3-ITD are treated for three hours at varying dosages of pacritinib (SB1518), and the amounts of pFLT3, pSTAT5, and pERK1/2 are measured. pFLT3, pSTAT5, pERK1/2, and pAkt all show dose-dependent decreases in response to paritinib, with IC50 values of 80, 40, 33, and 29 nM, respectively. When compared to FLT3-ITD in MV4-11 and MOLM-13 cells, the IC50 on auto-phosphorylation of FLT3-wt in RS4;11 is four times greater (IC50=600 nM). Nevertheless, STAT5 inhibition is observed at significantly lower Pacritinib concentrations (IC50=8 nM)[2].
ln Vivo
In the Ba/F3-JAK2V617F engraftment model, mice are dosed with 50 or 150 mg/kg poqd of pacritinib (SB1518) for 13 days, beginning 4 days after cell inoculation, in order to assess the drug's effectiveness. When the trial comes to an end, the vehicle control mice had hepatomegaly (1.3 fold) and splenomegaly (~7 fold), which are similar to the symptoms of symptomatic myelofibrosis patients. When administered at 150 mg/kg poqd, SB1518 therapy dramatically reduces all of these symptoms, resulting in a 60% (± 9%) normalization of spleen weight and a 92% (± 5%) normalization of liver weight. It is also well tolerated, causing minimal weight loss and no hematological toxicities, such as anemia or thrombocytopenia[1]. After a single oral administration of 10 mg/kg, pacritinib (SB1518) in rats exhibits moderately quick absorption (tmax=4 h), with a peak concentration of 114 ng/mL, an AUC of 599 ng·h/mL, and a terminal half-life of approximately 6 h. After a single oral dose of 3 mg/kg, dogs absorb pacritinib (SB1518) fast (tmax=2.0 h), peaking at ~12 ng/mL, with an AUC of 53 ng·h/mL and a terminal half-life of 3.4 h[3].
Animal Protocol
Dissolved in 0.5% methylcellulose (w/v) and 0.1% Tween-80 in H2O; 150 mg/kg; oral gavage
Human megakaryoblastic leukemia xenografts SET-2
References
[1]. Hart S, et al. SB1518, a novel macrocyclic pyrimidine-based JAK2 inhibitor for the treatment of myeloid and lymphoid malignancies. Leukemia. 2011 Nov;25(11):1751-9.
[2]. Hart S, et al. Pacritinib (SB1518), a JAK2/FLT3 inhibitor for the treatment of acute myeloid leukemia. Blood Cancer J. 2011 Nov;1(11):e44.
[3]. William AD, et al. Discovery of the macrocycle 11-(2-pyrrolidin-1-yl-ethoxy)-14,19-dioxa-5,7,26-triaza-tetracyclo[19.3.1.1(2,6).1(8,12)]heptacosa-1(25),2(26),3,5,8,10,12(27),16,21,23-decaene (SB1518), a potent Janus kinase 2/fms-like tyrosine kinase-3 (JA
These protocols are for reference only. InvivoChem does not independently validate these methods.
Physicochemical Properties
Molecular Formula
C28H32N4O3
Molecular Weight
472.58
CAS #
937272-79-2
Related CAS #
Pacritinib hydrochloride;1228923-43-0
SMILES
O(C1C([H])=C([H])C2=C([H])C=1C([H])([H])OC([H])([H])C([H])=C([H])C([H])([H])OC([H])([H])C1C([H])=C([H])C([H])=C(C=1[H])C1C([H])=C([H])N=C(N=1)N2[H])C([H])([H])C([H])([H])N1C([H])([H])C([H])([H])C([H])([H])C1([H])[H] |t:19|
InChi Key
HWXVIOGONBBTBY-ONEGZZNKSA-N
InChi Code
InChI=1S/C28H32N4O3/c1-2-13-32(12-1)14-17-35-27-9-8-25-19-24(27)21-34-16-4-3-15-33-20-22-6-5-7-23(18-22)26-10-11-29-28(30-25)31-26/h3-11,18-19H,1-2,12-17,20-21H2,(H,29,30,31)/b4-3+
Chemical Name
11-(2-pyrrolidin-1-yl-ethoxy)-14,19-dioxa-5,7,26-triaza-tetracyclo[19.3.1.1(2,6).1(8,12)]heptacosa-1(25),2(26),3,5,8,10,12(27),16,21,23-decaene
Synonyms
Pacritinib; SB-1518; Vonjo; SB1518; SB 1518
Storage

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Shipping Condition
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
Solubility Data
Solubility (In Vitro)
DMSO: 11 mg/mL (23.3 mM)
Water:<1 mg/mL
Ethanol:<1 mg/mL
Solubility (In Vivo)
Solubility in Formulation 1: ≥ 1 mg/mL (2.12 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 10.0 mg/mL clear DMSO stock solution to 400 μL of PEG300 and mix evenly; then add 50 μL of Tween-80 to the above solution and mix evenly; then add 450 μL of 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.

Solubility in Formulation 2: 1 mg/mL (2.12 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 10.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

View More

Solubility in Formulation 3: ≥ 0.3 mg/mL (0.63 mM) (saturation unknown) in 5% DMSO + 40% PEG300 + 5% Tween80 + 50% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.


 (Please use freshly prepared in vivo formulations for optimal results.)
Preparing Stock Solutions 1 mg 5 mg 10 mg
1 mM 2.1160 mL 10.5802 mL 21.1604 mL
5 mM 0.4232 mL 2.1160 mL 4.2321 mL
10 mM 0.2116 mL 1.0580 mL 2.1160 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.

Calculator

Molarity Calculator allows you to calculate the mass, volume, and/or concentration required for a solution, as detailed below:

  • Calculate the Mass of a compound required to prepare a solution of known volume and concentration
  • Calculate the Volume of solution required to dissolve a compound of known mass to a desired concentration
  • Calculate the Concentration of a solution resulting from a known mass of compound in a specific volume
An example of molarity calculation using the molarity calculator is shown below:
What is the mass of compound required to make a 10 mM stock solution in 5 ml of DMSO given that the molecular weight of the compound is 350.26 g/mol?
  • Enter 350.26 in the Molecular Weight (MW) box
  • Enter 10 in the Concentration box and choose the correct unit (mM)
  • Enter 5 in the Volume box and choose the correct unit (mL)
  • Click the “Calculate” button
  • The answer of 17.513 mg appears in the Mass box. In a similar way, you may calculate the volume and concentration.

Dilution Calculator allows you to calculate how to dilute a stock solution of known concentrations. For example, you may Enter C1, C2 & V2 to calculate V1, as detailed below:

What volume of a given 10 mM stock solution is required to make 25 ml of a 25 μM solution?
Using the equation C1V1 = C2V2, where C1=10 mM, C2=25 μM, V2=25 ml and V1 is the unknown:
  • Enter 10 into the Concentration (Start) box and choose the correct unit (mM)
  • Enter 25 into the Concentration (End) box and select the correct unit (mM)
  • Enter 25 into the Volume (End) box and choose the correct unit (mL)
  • Click the “Calculate” button
  • The answer of 62.5 μL (0.1 ml) appears in the Volume (Start) box
g/mol

Molecular Weight Calculator allows you to calculate the molar mass and elemental composition of a compound, as detailed below:

Note: Chemical formula is case sensitive: C12H18N3O4  c12h18n3o4
Instructions to calculate molar mass (molecular weight) of a chemical compound:
  • To calculate molar mass of a chemical compound, please enter the chemical/molecular formula and click the “Calculate’ button.
Definitions of molecular mass, molecular weight, molar mass and molar weight:
  • Molecular mass (or molecular weight) is the mass of one molecule of a substance and is expressed in the unified atomic mass units (u). (1 u is equal to 1/12 the mass of one atom of carbon-12)
  • Molar mass (molar weight) is the mass of one mole of a substance and is expressed in g/mol.
/

Reconstitution Calculator allows you to calculate the volume of solvent required to reconstitute your vial.

  • Enter the mass of the reagent and the desired reconstitution concentration as well as the correct units
  • Click the “Calculate” button
  • The answer appears in the Volume (to add to vial) box
In vivo Formulation Calculator (Clear solution)
Step 1: Enter information below (Recommended: An additional animal to make allowance for loss during the experiment)
Step 2: Enter in vivo formulation (This is only a calculator, not the exact formulation for a specific product. Please contact us first if there is no in vivo formulation in the solubility section.)
+
+
+

Calculation results

Working concentration mg/mL;

Method for preparing DMSO stock solution mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.

Method for preparing in vivo formulation:Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O,mix and clarify.

(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
             (2) Be sure to add the solvent(s) in order.

Clinical Trial Information
NCT Number Recruitment interventions Conditions Sponsor/Collaborators Start Date Phases
NCT06159491 Not yet recruiting Drug: Pacritinib
Drug: Azacitidine
Chronic Myelomonocytic
Leukemia
Douglas Tremblay January 2, 2024 Phase 1
Phase 2
NCT02765724 Completed Drug: Pacritinib Myelofibrosis CTI BioPharma January 2015 Phase 1
NCT05552183 Recruiting Drug: oral dose of 200 mg
pacritinib twice daily (BID)
Hepatic Impairment CTI BioPharma December 12, 2022 Phase 1
NCT04858256 Recruiting Drug: Pacritinib T-Cell Neoplasm
Lymphoproliferative Disorders
University of Michigan
Rogel Cancer Center
March 29, 2023 Phase 2
Biological Data
  • Pacritinib (SB1518)

    Pacritinib effectively blocks FLT3 signaling in FLT3-ITD (MV4-11, MOLM-13) or FLT3-wt (RS;4-11) cells.2011Nov;1(11):e44.

  • Pacritinib (SB1518)

    Pacritinib is efficacious in xenografts derived from cell lines harboring FLT3-ITD.2011Nov;1(11):e44.

  • Pacritinib (SB1518)

    Activated JAK2 signaling in MV4-11 cells after selective inhibition of FLT3 induces FLT3-TKI resistance.2011Nov;1(11):e44.

  • Pacritinib (SB1518)

    Pacritinib induces cell cycle arrest and apoptosis in FLT3-ITD- (MV4-11, MOLM-13) and FLT3-wt- (RS;4-11) harboring cancer cells.2011Nov;1(11):e44.

  • Pacritinib (SB1518)

    Pacritinib inhibits proliferation of AML cells with highest potency in FLT3-ITD harboring cells.2011Nov;1(11):e44.

  • Pacritinib (SB1518)

    Pacritinib blocks proliferation and induces apoptosis inex vivoexpanded primary AML blast cells.2011Nov;1(11):e44.

Contact Us Back to top