Tasquinimod (also known as ABR215050), a quinoline-3-carboxamide linomide analogue and an investigational drug, is a novel, and orally bioactive anti-angiogenic agent which potently inhibits HDAC4 allosterically with with potential anticancer activity. For the treatment of castration-resistant prostate cancer, Tasquinimod is presently being investigated in Phase 3 clinical trials.

Physicochemical Properties

Molecular Formula	C20H17F3N2O
Molecular Weight	406.36
Exact Mass	406.114
Elemental Analysis	C, 59.11; H, 4.22; F, 14.03; N, 6.89; O, 15.75.
CAS #	254964-60-8
Related CAS #	254964-60-8
PubChem CID	54682876
Appearance	White to light yellow solid powder
Density	1.4±0.1 g/cm3
Boiling Point	501.5±50.0 °C at 760 mmHg
Flash Point	257.1±30.1 °C
Vapour Pressure	0.0±1.4 mmHg at 25°C
Index of Refraction	1.606
LogP	2.63
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	3
Heavy Atom Count	29
Complexity	686
Defined Atom Stereocenter Count	0
SMILES	FC(C1C([H])=C([H])C(=C([H])C=1[H])N(C([H])([H])[H])C(C1C(N(C([H])([H])[H])C2C([H])=C([H])C([H])=C(C=2C=1O[H])OC([H])([H])[H])=O)=O)(F)F
InChi Key	ONDYALNGTUAJDX-UHFFFAOYSA-N
InChi Code	InChI=1S/C20H17F3N2O4/c1-24(12-9-7-11(8-10-12)20(21,22)23)18(27)16-17(26)15-13(25(2)19(16)28)5-4-6-14(15)29-3/h4-10,26H,1-3H3
Chemical Name	4-hydroxy-5-methoxy-N,1-dimethyl-2-oxo-N-[4-(trifluoromethyl)phenyl]quinoline-3-carboxamide
Synonyms	ABR-215050; ABR215050; BR-215050; Tasquinimod [INN]; 4-Hydroxy-5-methoxy-N,1-dimethyl-2-oxo-N-(4-(trifluoromethyl)-phenyl)-1,2-dihydroquinoline-3-carboxamide; 756U07KN1R; ABR 215050
HS Tariff Code	2934.99.9001
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)

Biological Activity

Targets	HDAC4 ( Kd = 10-30 nM )
ln Vitro	Tasquinimod blocks the growth of new tumors by inhibiting the deacetylation of HIF-1α that is dependent on HDAC4/N-CoR/HDAC3.[1] Tasquinimod also targets myeloid cells that have infiltrated the body. By preventing S100A9 from interacting with its ligand receptor, advanced glycation end products, and Toll-like receptor 4, it modifies local tumor immunity.[3]
ln Vivo	Through this mechanism, tasquinimod is effective as a monotherapeutic agent against human prostate, breast, bladder, and colon tumor xenografts, where its efficacy could be further enhanced in combination with a targeted thapsigargin prodrug (G202) that selectively kills tumor endothelial cells. Together, our findings define a mechanism of action of tasquinimod and offer a perspective on how its clinical activity might be leveraged in combination with other drugs that target the tumor microenvironment.[1] Based upon its superior potency (i.e., 30- to 60-fold more potent than linomide) in these assays and its lack of a proinflammation in the Beagle-dog, ABR-215050 (tasquinimod), Figure 1, was characterized for dose-response ability to inhibit the growth of a series of four additional human and rodent prostate cancer models in mice. Pharmacokinetic analysis following oral dosing documented that blood and tumor tissue levels of ABR-215050 as low as 0.5-1 microM are therapeutically effective. This efficacy is correlated with inhibition of angiogenesis in a variety of assays (endothelial capillary tube formation, aortic ring assay, chorioallantoic membrane assay, real-time tumor blood flow and PO(2) measurements, tumor blood vessel density, and tumor hypoxic and apoptotic fractions). Conclusions: Based upon its robust and consistent anti-angiogenic activity and thus tumor growth, ABR-215050 has entered clinical trials for the treatment of prostate cancer.[2] When nude mice bearing CWR-22RH human prostate tumors were treated with oral tasquinimod, there was a profound growth inhibition, associated with an up-regulation of TSP1 and a down- regulation of HIF-1 alpha protein, androgen receptor protein (AR) and glucose transporter-1 protein within the tumor tissue. Changes in TSP1 expression were paralleled by an anti-angiogenic response, as documented by decreased or unchanged tumor tissue levels of VEGF (a HIF-1 alpha down stream target) in the tumors from tasquinimod treated mice. Conclusions: We conclude that tasquinimod-induced up-regulation of TSP1 is part of a mechanism involving down-regulation of HIF1alpha and VEGF, which in turn leads to reduced angiogenesis via inhibition of the "angiogenic switch", that could explain tasquinimods therapeutic potential.[3] Tasquinimod (30 mg/kg/d p.o.) inhibits tumor growth in mice expressing human and rodent prostate cancer models by exhibiting anti-angiogenic activity. [2]
Enzyme Assay	Tasquinimod has a Kd of 10–30 nM for binding to the regulatory Zn2+ binding domain of HDAC4.Total HDAC and isotype specific HDAC enzymatic activity was assayed on a per cell basis using the appropriate substrates as described previously. Recombinant human HDAC isotypes were obtained commercially. These experiments were repeated a minimum of 3 independent times with 5 replicates per time point.[1] Surface plasmon resonance[1] SPR analysis was carried out with the Biacore 3000 system as described previously. Sensor chips, amine coupling kit, immobilization and running buffers, and regeneration solutions were as described previously. Binding to Tasquinimod was determined for human full length N-terminal GST-tagged HDAC4. GST-tagged HDAC4 was immobilized onto a CM5 chip through an amine-linkage. This chip was used to determine binding of full length human N-CoR. These experiments were repeated 3 independent times.
Cell Assay	CWR-22RH and LNCaP (ATCC) are two human prostate cancer cell lines that express PSA and have a mutated androgen receptor. Despite being androgen independent, they both show sensitivity to androgen stimulation of growth. The in vitro exposure of hormone-independent cell lines LNCaP19 and DU145 to Tasquinimod (0.1-100 μM) is followed by an assessment of TSP1 induction. While LNCAP19 is cultivated in RPMI-medium with 10% hormone free (RDCC) FCS, CWR-22RH, LNCaP, and DU145 are grown in RPMI Medium 1640 containing 10% FCS and L-Glutamine mixture.
Animal Protocol	Nude BALB/c mice were used for subcutaneous implantation of human prostate tumor cells LNCaP and CWR-22RH. All animal experiments were conducted in accordance with the Bioethics Committee guidelines in Lund, Sweden. Tumor growth was measured with a microcaliper twice a week throughout the experiment, and the final tumor burden was measured by weight on the day of termination of the experiment. Distribution of tasquinimod at 1 mg/kg/day and 10 mg/kg/day (administered orally via the drinking water) started on day 7 after inoculation.[4] Tumor bearing mice (LNCaP inoculated in nude mice) were treated with tasquinimod at 10 mg/kg (ad.lib.) and the tumors of each of the 2 different treatment groups were excised after 24 h of treatment (start day 14 or day 21 after inoculation) and total RNA was isolated.[4] Therefore, linomide analogs and tasquinimod were initially screened to determine their in vivo potency to inhibit growth of the Dunning R-3327 AT-1 rat prostate cancer model in rats and their potency to inhibit angiogenesis in a Matrigel assay in mice.[2] Mice: The LNCaP and CWR-22RH human prostate tumor cells are subcutaneously implanted into naked BALB/c mice. For the duration of the experiment, tumor growth is measured twice a week using a microcaliper, and on the day of experiment termination, the final tumor burden is determined by weight. After the inoculation, Tasquinimod was first distributed orally on day seven at doses of 1 mg/kg and 10 mg/kg per day (given through drinking water).
ADME/Pharmacokinetics	Tasquinimod has been found to have a low clearance of 0.19 L/h at 0.5 mg and 0.22 L/h at 1 mg dose level, making increase in systemic exposure lesser than the dose increase. The volume of distribution is 5.9 L, the elimination half-life is 40±16 hours, and the maximum plasma concentrations occur at 2.6 hours. Area under the curve steady state amounts to 4.8 μmol/h. Co-administration with food has not been found to affect the pharmacokinetic properties of tasquinimod. No relationship between pharmacokinetic parameters and race, ethnicity, or hepatic function has been identified. https://www.tandfonline.com/doi/full/10.2147/OTT.S53524#d1e353
Toxicity/Toxicokinetics	Tasquinimod, an S100A9 inhibitor, is well tolerated in pts with RRMM as a single-agent and in combination with IRd, with a single-agent MTD of 1 mg daily after a 1-week dose escalation. ;
References	[1]. Cancer Res . 2013 Feb 15;73(4):1386-99. [2]. Prostate . 2006 Dec 1;66(16):1768-78. [3]. Cancer Chemother Pharmacol . 2014 Jan;73(1):1-8. [4]. Mol Cancer . 2010 May 17:9:107.
Additional Infomation	Tasquinimod is a quinoline-3-carboxamide linomide analogue with antiangiogenic and potential antineoplastic activities. Tasquinimod has been shown to decrease blood vessel density but the exact mechanism of action is not known. This agent has also been shown to augment the antineoplastic effects of docetaxel and androgen ablation in a murine model of prostate cancer involving human prostate cancer xenografts. The quinoline-3-carboxamide anti-angiogenic agent, tasquinimod, enhances the anti-prostate cancer efficacy of androgen ablation and taxotere without effecting serum PSA directly in human xenografts Tasquinimod is a quinoline-3-carboxamide linomide analogue with antiangiogenic and potential antineoplastic activities. Tasquinimod has been shown to decrease blood vessel density but the exact mechanism of action is not known. This agent has also been shown to augment the antineoplastic effects of docetaxel and androgen ablation in a murine model of prostate cancer involving human prostate cancer xenografts. Drug Indication Investigated for use/treatment in prostate cancer.

Solubility Data

Solubility (In Vitro)

DMSO: ~81 mg/mL (~199.3 mM) Water: <1 mg/mL Ethanol: ~11 mg/mL warmed (~27.1 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.15 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. Solubility in Formulation 2: ≥ 2.5 mg/mL (6.15 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in 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 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. Solubility in Formulation 3: ≥ 2.5 mg/mL (6.15 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. Solubility in Formulation 4: ≥ 2.5 mg/mL (6.15 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. Solubility in Formulation 5: ≥ 2.5 mg/mL (6.15 mM) (saturation unknown) in 5% DMSO + 95% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. 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. Solubility in Formulation 6: 5% DMSO+30% PEG 300+ddH2O: 8mg/mL  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.4609 mL	12.3044 mL	24.6087 mL
	5 mM	0.4922 mL	2.4609 mL	4.9217 mL
	10 mM	0.2461 mL	1.2304 mL	2.4609 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.