CDK9/cyc T2 (Ki = 0.626 nM); CDK9/CycT1 (Ki = 1.68 nM); CDK6/cycD1 (Ki = 2.92 nM); CDK4/Cyc D1 (Ki = 3.96 nM); CDK1/cycB (Ki = 5.4 nM); CDK1/cyc A (Ki = 9.1 nM)
Voruciclib targets cyclin-dependent kinases, particularly CDK9. It is a potent CDK9 inhibitor, but also inhibits CDK4 and CDK6. By inhibiting CDK9, it reduces the transcription of Mcl-1, leading to decreased Mcl-1 protein levels.

Voruciclib (0.5-5 µM; 6 hours) exhibits targeted downregulation of MCL-1 in both ABC and GCB subtypes[1].
Voruciclib hydrochloride has ki values of 0.626 nM, 1.68 nM, 2.92 nM, 3.96 nM, 5.4 nM, and 9.1 nM for each target, such as CDK9/cyc T2, CDK9/cyc T1, CDK6/cyc D1, CDK4/cyc D1, CDK1/cyc B, and CDK1/cyc A[1].

In U2932, RIVA, SU-DHL-4 (six days per week for four weeks) and NU-DHL-1 (five days per week for three weeks) models of DLBCL, the combination of Voruciclib hydrochloride (200 mpk; oral gavage) and Venetoclax (10 mpk, 1 mpk, 50 mpk, and 25 mpk in each of these models, respectively) leads to enhanced tumor growth inhibition compared to either drug alone1.

Reaction Biology IC50 profiling[1]
Rank order of sensitivity of 48 kinases to voruciclib hydrochloride was determined at Reaction Biology Corp. Kinase activity was measured using a filter binding assay with radioactive γ-33P-ATP as phosphate donor. The ATP concentration was near the Km values for the respective kinases. For each kinase, an IC50 value was calculated from a 10-point concentration curve of the test article and converted to Ki values. The 48 kinases studied here had been identified in previous screening experiments as the most promising target candidates.
In vitro enzyme/receptor binding (non-cell) assays for Voruciclib involve measuring its inhibition of CDK kinase activity. Purified CDK9, CDK4, CDK6, and other kinases are incubated with ATP and a substrate in the presence of varying concentrations of Voruciclib. Kinase activity is measured, and IC50 values are calculated.

Cell Line: U2932, RIVA, OCI-LY10 cells (ABC subtype), NU-DHL-1, SU-DHL-4, SU-DHL-6 cells (GCB subtype)
Concentration: 0.5 µM, 1 µM, 2 µM, 3 µM, 4 µM, 5 µM
Incubation Time: 6 hours
Result: Showed targeted downregulation of MCL-1 in both ABC and GCB subtypes.
In vitro cell-based experiments for Voruciclib are conducted using cancer cell lines, such as AML, CLL, and DLBCL cells. Cells are treated with Voruciclib, and cell proliferation, apoptosis, and Mcl-1 protein levels are assessed.

ABC subtypes (U2932, RIVA, OCI-LY10), GCB subtypes (SU-DHL-4, NU-DHL-1) xenografted in Female NOD.CB17-Prkdcscid/NCrHsd mice
200 mpk
Oral gavage; U2932, RIVA, SU-DHL-4 (six days per week for 4 weeks), OCI-LY10 (six days per week for 2 weeks), NU-DHL-1 (five days per week for 3 weeks)

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For systemic drug efficacy studies, mice were enrolled when tumors reached an average volume of 150–200 mm3. Assignment to treatment groups was carried out via stratified randomization. Tumor dimensions were measured twice a week using digital calipers along with recording of body weight. Tumor volume was calculated using formula V = π/6 (length x width x height) in mm3 . Animals were removed from the study when either any one of the three measured dimensions of the tumor exceeded 2 cm, volume exceeded 2000 mm3, ulceration was observed or if body weight loss greater than 20% was recorded. Drug formulations: voruciclib was formulated in 0.1% methylcellulose and venetoclax in 60% phosal 50, 30% PEG 400, 10% ethanol, both administered orally. Control cohorts were administered vehicles of both drugs, and each single agent cohort was administered the vehicle of the other drug. Depending on the assigned treatment, venetoclax (or its vehicle) was followed by voruciclib (or its vehicle) with 30 mins in between administrations to allow for gastric clearance as per veterinary recommendation. Model specific dosing regimens: U2932: venetoclax at 10 mpk twice a week, voruciclib 200 mpk six days per week for a total duration of 4 weeks; RIVA: venetoclax at 1 mpk twice a week, voruciclib 200 mpk six days per week for a total duration of four weeks; OCI-LY10: venetoclax at 25 mpk twice a week, voruciclib 200 mpk six days per week for a total duration of two weeks; NU-DHL-1: venetoclax at 50 mpk once a week, voruciclib at 200 mpk five days per week for a total duration of three weeks; SU-DHL-4: venetoclax at 25 mpk and voruciclib 200 mpk both six days per week for a total duration of four weeks. The venetoclax + voruciclib combination treatment cohort for each model received both drugs at the same doses and frequencies as the corresponding single agents.
In vivo animal experiments for Voruciclib are performed in xenograft mouse models of AML and other cancers. Voruciclib is administered orally, and tumor growth, survival, and Mcl-1 levels are assessed.

Voruciclib is orally bioavailable. Its pharmacokinetic profile is suitable for in vivo studies.

Voruciclib is well-tolerated in preclinical studies. No significant toxicity has been reported.

[1]. Voruciclib, a clinical stage oral CDK9 inhibitor, represses MCL-1 and sensitizes high-risk Diffuse Large B-cell Lymphoma to BCL2 inhibition. Sci Rep. 2017 Dec 21;7(1):18007.

Voruciclib is currently undergoing clinical trial NCT03547115 (a phase I study of Voruciclib in patients with B-cell malignancies or acute myeloid leukemia). Voruciclib is a cyclin-dependent kinase (CDK) inhibitor with potential antitumor activity. After administration, Voruciclib selectively inhibits cyclin-dependent kinases 4 (CDK4) and 6 (CDK6). This inhibits phosphorylation of early G1 phase retinoblastoma (Rb) proteins, thereby preventing CDK-mediated G1-S phase transition and leading to cell cycle arrest. This inhibits DNA replication and reduces tumor cell proliferation. CDK4 and 6 are serine/threonine kinases upregulated in various tumor cell types and play a crucial role in the regulation of cell cycle progression.
Voruciclib is also known as P1446A-05 and P1446A. It is a research compound for cancer. It has been evaluated in clinical trials for AML and B-cell malignancies.

C22H19CLF3NO5

469.8412

469.09

C, 56.24; H, 4.08; Cl, 7.55; F, 12.13; N, 2.98; O, 17.03

1000023-04-0

Voruciclib hydrochloride;1000023-05-1;(2S,3R)-Voruciclib hydrochloride;rel-(2S,3R)-Voruciclib;1253731-24-6; 1000023-04-0; 2505206-37-9 (malonate)

67409219

Light yellow to yellow solid powder

4.261

3

9

3

32

750

2

ClC1C=C(C(F)(F)F)C=CC=1C1=CC(C2=C(C=C(C(=C2O1)[C@@H]1CCN(C)[C@@H]1CO)O)O)=O

MRPGRAKIAJJGMM-OCCSQVGLSA-N

InChI=1S/C22H19ClF3NO5/c1-27-5-4-12(14(27)9-28)19-15(29)7-16(30)20-17(31)8-18(32-21(19)20)11-3-2-10(6-13(11)23)22(24,25)26/h2-3,6-8,12,14,28-30H,4-5,9H2,1H3/t12-,14+/m1/s1

2-[2-chloro-4-(trifluoromethyl)phenyl]-5,7-dihydroxy-8-[(2R,3S)-2-(hydroxymethyl)-1-methylpyrrolidin-3-yl]chromen-4-one

Voruciclib; 1000023-04-0; Voruciclib [INN]; P1446A-05; 2-[2-chloro-4-(trifluoromethyl)phenyl]-5,7-dihydroxy-8-[(2R,3S)-2-(hydroxymethyl)-1-methylpyrrolidin-3-yl]chromen-4-one; W66XP666AM; CHEMBL3905910; P-1446;

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: ~50 mg/mL (~106.4 mM)

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.)