DNA-PK (IC50 = 13 nM); mTOR (IC50 = 21 nM); mTORC1; mTORC2; PI3Kα (IC50 = 852 nM)
CC-115 inhibits PC-3 cells proliferation with an IC50 of 138 nM. Only one kinase other than mTOR kinase is identified with more than 50% inhibition in a kinase selectivity assessment against a panel of 250 protein kinases at 3 μM (cFMS 57%, IC50=2.0 μM). The remaining PI3K related kinases (PIKKs) tested include PI3K-alpha (IC50=0.85 μM), ATR (50% inhibition at 30 μM), and ATM (IC50>30 μM). Of the PI3K related kinases (PIKKs) tested, CC-115 exhibits 40 to >1000 fold selectivity against the remaining PIKKs. The inhibitory concentrations (IC50) of CC-115 for a panel of CYP enzymes are >10 μM and >33 μM, respectively, for the hERG (human ether-a-go-go-related gene) ion channel[1].
mTOR kinase (IC50 = 0.021 µM)
DNA-PK (IC50 = 0.015 µM)
PI3K-alpha (IC50 = 0.85 µM)
cFMS (CSF1R) (57% inhibition at 3 µM; IC50 = 2.0 µM)

CC-115 inhibits PC-3 cells proliferation with an IC50 of 138 nM. Only one kinase other than mTOR kinase is identified with more than 50% inhibition in a kinase selectivity assessment against a panel of 250 protein kinases at 3 μM (cFMS 57%, IC50=2.0 μM). The remaining PI3K related kinases (PIKKs) tested include PI3K-alpha (IC50=0.85 μM), ATR (50% inhibition at 30 μM), and ATM (IC50>30 μM). Of the PI3K related kinases (PIKKs) tested, CC-115 exhibits 40 to >1000 fold selectivity against the remaining PIKKs. The inhibitory concentrations (IC50) of CC-115 for a panel of CYP enzymes are >10 μM and >33 μM, respectively, for the hERG (human ether-a-go-go-related gene) ion channel[1].

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CC-115 inhibited phosphorylation of Akt at Ser473 (pAkt(S473)) in PC-3 cancer cells with an IC50 of 0.022 µM.
[1]
CC-115 inhibited PC-3 cell proliferation with an IC50 of 0.138 µM.
[1]
In a kinase selectivity panel of 250 protein kinases tested at 3 µM, only one kinase other than mTOR showed >50% inhibition (cFMS, 57%). Among the PIKK family kinases, CC-115 was equipotent against DNA-PK (IC50 = 0.015 µM) and showed 40 to >1000-fold selectivity against PI3K-alpha (IC50 = 0.85 µM), ATR (50% inhibition at 30 µM), and ATM (IC50 > 30 µM).
[1]

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CC-115 inhibited phosphorylation of Akt at Ser473 (pAkt(S473)) in PC-3 cancer cells with an IC50 of 0.022 µM.[1]
CC-115 inhibited PC-3 cell proliferation with an IC50 of 0.138 µM.[1]
In a kinase selectivity panel of 250 protein kinases tested at 3 µM, only one kinase other than mTOR showed >50% inhibition (cFMS, 57%). Among the PIKK family kinases, CC-115 was equipotent against DNA-PK (IC50 = 0.015 µM) and showed 40 to >1000-fold selectivity against PI3K-alpha (IC50 = 0.85 µM), ATR (50% inhibition at 30 µM), and ATM (IC50 > 30 µM).[1]

CC-115 hydrochloride shows good in vivo PK profiles across multiple species with 53%, 76% and ~100% oral bioavailability in mouse, rat and dog, respectively. Lower doses of CC-115, such as 0.25, 0.5, and 1 mg/kg bid or 1 mg/kg qd, are tested, and tumor volume reductions of 46%, 57%, 66%, and 57%, respectively, are seen. The inhibition of CC-115 lasts for 24 hours. At a dose of 1 mg/kg, CC-115 exhibits significant inhibition at 1 and 3 hours, continuing to exhibit inhibition at 10 hours. Both a once-daily (qd) and twice-daily (bid) dosing schedule is used to evaluate CC-115[1].

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In a single-dose pharmacokinetic/pharmacodynamic (PK/PD) study in PC-3 tumor-bearing mice, oral administration of CC-115 at 10 mg/kg or 1 mg/kg led to significant and sustained inhibition of both mTORC1 (pS6) and mTORC2 (pAkt S473) biomarkers in tumors for up to 24 hours (10 mg/kg) and 10 hours (1 mg/kg), correlating with plasma drug levels.[1]
In a PC-3 prostate cancer xenograft model, oral administration of CC-115 demonstrated dose-dependent tumor growth inhibition. Tumor volume reductions (TVR) of 66%, 5 7%, and 46% were observed at doses of 1 mg/kg twice daily (bid), 0.5 mg/kg bid, and 0.25 mg/kg bid, respectively. A once-daily (qd) dose of 1 mg/kg also resulted in a 57% TVR. The minimal efficacious dose was determined to be 1 mg/kg bid.[1]

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In a single-dose pharmacokinetic/pharmacodynamic (PK/PD) study in PC-3 tumor-bearing mice, oral administration of CC-115 at 10 mg/kg or 1 mg/kg led to significant and sustained inhibition of both mTORC1 (pS6) and mTORC2 (pAkt S473) biomarkers in tumors for up to 24 hours (10 mg/kg) and 10 hours (1 mg/kg), correlating with plasma drug levels.[1]
In a PC-3 prostate cancer xenograft model, oral administration of CC-115 demonstrated dose-dependent tumor growth inhibition. Tumor volume reductions (TVR) of 66%, 5 7%, and 46% were observed at doses of 1 mg/kg twice daily (bid), 0.5 mg/kg bid, and 0.25 mg/kg bid, respectively. A once-daily (qd) dose of 1 mg/kg also resulted in a 57% TVR. The minimal efficacious dose was determined to be 1 mg/kg bid.[1]

An HTR-FRET substrate phosphorylation assay is employed for mTOR kinase. The mobility shift assay format is used to outsource the determination of PI3K'sIC50. Compounds (such as CC-115) are evaluated in comparison to ATP concentrations at approximately the Km for the assay, with average ATP Km values of 15 M and 50 M for the mTOR and PI3K assays, respectively[1].

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An HTR-FRET (Homogeneous Time-Resolved Fluorescence Resonance Energy Transfer) substrate phosphorylation assay was employed to determine the inhibitory activity of compounds against mTOR kinase. The assay measures the phosphorylation of a specific substrate by mTOR kinase using FRET detection. Compounds were assessed against ATP concentrations near the Km for the assay (average Km ~15 µM).[1]
The IC50 values for PI3K-alpha were determined using a mobility shift assay format. This assay separates phosphorylated and non-phosphorylated substrates based on their electrophoretic mobility. Compounds were assessed against ATP concentrations near the Km for the assay (average Km ~50 µM).[1]

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An HTR-FRET (Homogeneous Time-Resolved Fluorescence Resonance Energy Transfer) substrate phosphorylation assay was employed to determine the inhibitory activity of compounds against mTOR kinase. The assay measures the phosphorylation of a specific substrate by mTOR kinase using FRET detection. Compounds were assessed against ATP concentrations near the Km for the assay (average Km ~15 µM).[1]
The IC50 values for PI3K-alpha were determined using a mobility shift assay format. This assay separates phosphorylated and non-phosphorylated substrates based on their electrophoretic mobility. Compounds were assessed against ATP concentrations near the Km for the assay (average Km ~50 µM).[1]

In growth media, PC-3 cells are cultured. In order to measure the levels of pS6 and pAkt, cells are treated for 1 hour for biomarker studies. For experiments on cell proliferation, cells are given a substance (like CC-115) and then allowed to grow for 72 hours. All data are normalized and shown as a percentage of the cells that received DMSO treatment. The IC50 values of the results are then presented[1].

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For biomarker inhibition studies, PC-3 cells were treated with compounds for 1 hour. Following treatment, cells were lysed and the levels of phosphorylated S6 (pS6) and phosphorylated Akt at Ser473 (pAkt S473) were quantified using an electrochemiluminescence detection platform. Results were normalized to DMSO-treated control cells and expressed as IC50 values.[1]
For cell proliferation assays, PC-3 cells were seeded and treated with compounds. The cells were then allowed to grow for 72 hours. Cell viability/proliferation was assessed at the end of the incubation period. Data were normalized to DMSO-treated controls and expressed as IC50 values.[1]

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For biomarker inhibition studies, PC-3 cells were treated with compounds for 1 hour. Following treatment, cells were lysed and the levels of phosphorylated S6 (pS6) and phosphorylated Akt at Ser473 (pAkt S473) were quantified using an electrochemiluminescence detection platform. Results were normalized to DMSO-treated control cells and expressed as IC50 values.[1]
For cell proliferation assays, PC-3 cells were seeded and treated with compounds. The cells were then allowed to grow for 72 hours. Cell viability/proliferation was assessed at the end of the incubation period. Data were normalized to DMSO-treated controls and expressed as IC50 values.[1]

Mice: Encouraged by the exposures seen, CC-115 has advanced into single dose PK/PD studies evaluating the inhibition of the mTOR pathway biomarker in tumor-bearing mice. Plasma and tumor samples are taken at various time points for analysis after PC-3 tumor-bearing mice are given a single dose of CC-115, dosed orally at either 1 or 10 mg/kg. The level of biomarker inhibition is correlated with plasma compound levels, and significant inhibition of both mTORC1 (pS6) and mTORC2 (pAktS473) is seen for all compounds.

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For single-dose PK/PD biomarker studies, mice bearing PC-3 tumor xenografts were administered a single oral dose of the test compound (1 or 10 mg/kg) formulated as a suspension in 0.5% carboxymethyl cellulose and 0.25% Tween-80. Plasma and tumor samples were collected at various time points (1, 3, 6, 10, 24 hours) post-dose for analysis of compound concentration and biomarker (pS6, pAkt) inhibition.[1]
For multi-day efficacy studies, mice bearing established PC-3 tumors (~125 mm³) were treated orally with the test compound, formulated as a suspension in 0.5% carboxymethyl cellulose and 0.25% Tween-80. Dosing regimens included once daily (qd) or twice daily (bid, with doses separated by 10 hours). Treatment continued for 21 days, and tumor volumes were measured periodically. Tumor volume reduction was calculated relative to vehicle-treated controls.[1]

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For single-dose PK/PD biomarker studies, mice bearing PC-3 tumor xenografts were administered a single oral dose of the test compound (1 or 10 mg/kg) formulated as a suspension in 0.5% carboxymethyl cellulose and 0.25% Tween-80. Plasma and tumor samples were collected at various time points (1, 3, 6, 10, 24 hours) post-dose for analysis of compound concentration and biomarker (pS6, pAkt) inhibition.[1]
For multi-day efficacy studies, mice bearing established PC-3 tumors (~125 mm³) were treated orally with the test compound, formulated as a suspension in 0.5% carboxymethyl cellulose and 0.25% Tween-80. Dosing regimens included once daily (qd) or twice daily (bid, with doses separated by 10 hours). Treatment continued for 21 days, and tumor volumes were measured periodically. Tumor volume reduction was calculated relative to vehicle-treated controls.[1]

Following a single oral administration (5 mg/kg, suspension) to rats, the Cmax of CC-115 was 1.67 ± 0.42 µM, the AUC(0-∞) was 27.46 ± 1.44 µM·hr, and the oral bioavailability (F%) was 78 ± 20%. [1] Following intravenous administration (2 mg/kg) to rats, the clearance (CL) was 7.35 ± 2.13 mL/min/kg, and the mean residence time (MRT) was 4.3 ± 0.4 h. [1] In vitro metabolic stability assessed in rat and human liver S9 fractions showed 100% compound residue in both species after 60 min. [1] In vitro permeability assessed in Caco-2 cells showed an apparent permeability (Papp AB) of 30.4 x 10⁻⁶ cm/s. The efflux ratio (BA/AB) was 1.3, indicating good permeability and low efflux potential. [1]
It has been reported that the cross-species oral bioavailability in mice, rats and dogs was 53%, 76% and about 100%, respectively. [1]
In rats, after a single oral administration (5 mg/kg, suspension), the Cmax of CC-115 was 1.67 ± 0.42 µM, the AUC(0-∞) was 27.46 ± 1.44 µM·hr, and the oral bioavailability (F%) was 78 ± 20%. [1]
In rats, after intravenous injection (2 mg/kg), the clearance (CL) was 7.35 ± 2.13 mL/min/kg and the mean residence time (MRT) was 4.3 ± 0.4 h. [1]
In vitro metabolic stability assessment in rat and human livers showed 100% compound residue in the S9 fraction after 60 minutes. [1]
In vitro permeability assessment in Caco-2 cells showed an apparent permeability (Papp AB) of 30.4 x 10⁻⁶ cm/s and an efflux ratio (BA/AB) of 1.3, indicating good permeability and low efflux potential. [1]
The cross-species oral bioavailability of this compound in mice, rats, and dogs was reported to be 53%, 76%, and approximately 100%, respectively. [1]

CC-115 exhibits IC50 values greater than 10 µM against a range of cytochrome P450 (CYP) enzymes. [1]
It also shows an IC50 value greater than 33 µM for inhibition of the hERG (human ether-a-go-go related gene) ion channel. [1]
In a single-point screening at 10 µM, only phosphodiesterase 3 (PDE3) showed greater than 50% inhibition (IC50 = 0.63 µM) against a range of receptors and enzymes. [1]
CC-115 was negative in the Ames bacterial reverse mutation assay, regardless of whether metabolic activation (S9 fraction) was performed. [1]
CC-115 exhibits IC50 values greater than 10 µM against a range of cytochrome P450 (CYP) enzymes. [1]
It also shows an IC50 value greater than 33 µM for inhibition of the hERG (human ether-a-go-go related gene) ion channel. [1] The IC50 of the hERG (human ether-a-go-go related gene) ion channel is > 33 µM. [1]
In a 10 µM single-point screening against a range of receptors and enzymes, only phosphodiesterase 3 (PDE3) showed > 50% inhibition (IC50 = 0.63 µM). [1]
CC-115 was negative in the Ames bacterial reverse mutation assay, regardless of whether metabolic activation (S9 fraction) was performed. [1]

[1]. Optimization of a Series of Triazole Containing Mammalian Target of Rapamycin (mTOR) Kinase Inhibitors and the Discovery of CC-115. J Med Chem. 2015 Jul 23;58(14):5599-5608.

CC-115 is a highly potent, selective, and orally bioavailable dual inhibitor of mTOR kinase and DNA-dependent protein kinase (DNA-PK). It was discovered through structure-activity relationship (SAR) optimization of a triazole-containing 3,4-dihydropyrazino[2,3-b]pyrazin-2(1H)-one series of compounds. [1] CC-115 blocks downstream signaling pathways involved in cell growth and survival by inhibiting the mTORC1 and mTORC2 complex. The additional inhibition of DNA-PK, a key enzyme in the DNA damage response, by CC-115 may provide a unique mechanism compared to other selective mTOR inhibitors. [1] Based on its favorable preclinical profile, including strong in vivo efficacy, good pharmacokinetics, and good in vitro safety, CC-115 was selected for clinical development and is in Phase I clinical trials at the time of publication. [1]

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CC-115 is a potent, selective, and orally bioavailable dual inhibitor of mTOR kinase and DNA-dependent protein kinase (DNA-PK). CC-115 was discovered through structure-activity relationship (SAR) optimization of a triazole-containing 3,4-dihydropyrazino[2,3-b]pyrazin-2(1H)-one series of compounds. [1]
CC-115 blocks downstream signaling pathways involved in cell growth and survival by inhibiting the mTORC1 and mTORC2 complex. In addition, CC-115 also inhibits DNA-PK, a key enzyme in the DNA damage response, which may make its mechanism of action different from other selective mTOR inhibitors. [1]
Based on its promising preclinical results, including potent in vivo efficacy, good pharmacokinetics, and good in vitro safety, CC-115 was selected for clinical development and is currently in Phase I clinical trials at the time of publication. [1]

C₁₆H₁₇CLN₈O

372.81

372.121

1300118-55-1

CC-115;1228013-15-7

67153895

Light yellow to yellow solid

3

7

3

26

491

0

[H]Cl.O=C1CN=C2C(N1CC)=NC(C3=C(C)N=C(C4=NN=CN4)C=C3)=CN2

RDIPJCOMBMBHJF-UHFFFAOYSA-N

InChI=1S/C16H16N8O.ClH/c1-3-24-13(25)7-18-15-16(24)22-12(6-17-15)10-4-5-11(21-9(10)2)14-19-8-20-23-14;/h4-6,8H,3,7H2,1-2H3,(H,17,18)(H,19,20,23);1H

5-ethyl-3-[2-methyl-6-(1H-1,2,4-triazol-5-yl)pyridin-3-yl]-7,8-dihydropyrazino[2,3-b]pyrazin-6-one;hydrochloride

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: >67 mg/mL (199.2 mM)
Water: N/A
Ethanol: N/A

Solubility in Formulation 1: 100 mg/mL (268.23 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)