Imaradenant (AZD4635; HTL-1071) is a novel, potent, selective, orally bioavailable small molecule inhibitor of the adenosine A2A receptor (A2AR) (Ki = 1.7 nM) with potential anticancer immunomodulatory activity. It binds to human A2AR and exhibits > 30-fold selectivity over other adenosine receptors, making it a promising agent for cancer immunotherapy. By inhibiting A2aR signaling, AZD4635 can improve antitumor immunity and lessen the burden of tumors. In patients with solid cancers, AZD4635 is presently being investigated in a Phase 1 clinical trial both as a single treatment and in conjunction with durvalumab (anti-PD-L1 Ab). Tumors use the microenvironment's extracellular adenosine accumulation as a means of evading immune surveillance.

Physicochemical Properties

Molecular Formula	C15H11CLFN5
Molecular Weight	315.73
Exact Mass	315.069
Elemental Analysis	C, 57.06; H, 3.51; Cl, 11.23; F, 6.02; N, 22.18
CAS #	1321514-06-0
Related CAS #	1321514-06-0
PubChem CID	86676119
Appearance	Solid powder
LogP	3.864
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	2
Heavy Atom Count	22
Complexity	366
Defined Atom Stereocenter Count	0
SMILES	ClC1=CC(=CC(C)=N1)C1C(C2C=CC(=CC=2)F)=NC(N)=NN=1
InChi Key	NCWQLHHDGDXIJN-UHFFFAOYSA-N
InChi Code	InChI=1S/C15H11ClFN5/c1-8-6-10(7-12(16)19-8)14-13(20-15(18)22-21-14)9-2-4-11(17)5-3-9/h2-7H,1H3,(H2,18,20,22)
Chemical Name	6-(2-chloro-6-methylpyridin-4-yl)-5-(4-fluorophenyl)-1,2,4-triazin-3-amine
Synonyms	Imaradenant; HTL-1071; AZD-4635; HTL 1071; AZD 4635; HTL1071; AZD4635
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	A2AR ( Ki = 1.7 nM )
ln Vitro	In vitro activity: In CHO cells stably expressing human A2AR, the IC50s of AZD4635 for inhibition of cAMP production are 0.79, 10.0 and 142.9 nM in the presense of 0.1, 1 and 10 μM adenosine, respectively[1].
ln Vivo	AZD4635's blockade of A2AR signaling may lessen tumor burden and improve antitumor immunity[1].
Enzyme Assay	It exhibits >30-fold selectivity over other adenosine receptors and binds to human A2AR with a Ki of 1.7 nM.
Cell Assay	Adenosine at concentrations ranging from 0.1 to 10 μM was incubated with CHO cells that were stably expressing human A2AR. The IC50 of AZD4635 for the inhibition of cAMP production was 0.79, 10.0, and 142.9 nM, respectively, in the presence of 0.1, 1, and 10 μM adenosine. AZD4635 was found to reverse suppression and restore IFNγ secretion in cells incubated with 5’-N-ethylcarboxamidoadenosine (NECA), a stable analogue of adenosine, in an ex vivo CD8+ T cell assay.
Animal Protocol	N/A Syngeneic mouse tumor models
References	[1]. Cancer Res (2017) 77 (13_Supplement): 5580.
Additional Infomation	Imaradenant is under investigation in clinical trial NCT03381274 (Oleclumab (MEDI9447) Egfrm NSCLC Novel Combination Study). Imaradenant is an orally bioavailable antagonist of the adenosine A2A receptor (A2AR; ADORA2A), with potential immunomodulating and antineoplastic activities. Upon administration, imaradenant selectively binds to and inhibits A2AR expressed on T-lymphocytes. This blocks tumor-released adenosine from interacting with A2AR and prevents the adenosine/A2AR-mediated inhibition of T-lymphocytes. This results in the proliferation and activation of T-lymphocytes, and stimulates a T-cell-mediated immune response against tumor cells. A2AR, a G protein-coupled receptor, is highly expressed on the cell surfaces of T-cells and, upon activation by adenosine, inhibits T-cell proliferation and activation. Adenosine is often overproduced by cancer cells and plays a key role in immunosuppression.

Solubility Data

Solubility (In Vitro)

DMSO: >10mM Water: N/A Ethanol: N/A

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (6.59 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. Solubility in Formulation 2: ≥ 2.08 mg/mL (6.59 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. Solubility in Formulation 3: 5% DMSO + 95% Corn oil: 1.1mg/ml (3.48mM)  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.1673 mL	15.8363 mL	31.6726 mL
	5 mM	0.6335 mL	3.1673 mL	6.3345 mL
	10 mM	0.3167 mL	1.5836 mL	3.1673 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.