DNA-PK (IC50 <3 nM)

M3814 sensitized multiple tumor cell lines to radiation therapy in vitro [2].

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M3814 targets tumor cell growth and survival by inhibiting a critical DSB DNA damage repair mechanism. The antitumor effect of M3814 is dependent on the functionality of DNA repair and checkpoint signaling in cancer cells, which have a lowered ability to cope with DSBs, leading to cell death. Hence, the rationale of DNA-PK inhibition is to increase the amount of DSB DNA damage generated by IR. The objective of the series of nonclinical experiments was to demonstrate that IR together with M3814 was more efficacious than IR alone [1].

In combination with IR, M3814 showed efficacy in all of the 6 mouse models of human cancer as demonstrated by a strong potentiation of the effect of IR. In all models, a dose of 2 Gy administered daily for 1 week in combination with M3814 induced statically significant tumor growth inhibition compared to IR alone. In 2 models, FaDu and NCIH460, M3814 induced tumor regression. In the FaDu model, no tumor regrowth (duration of the experiment >100 days) was observed in the combination arm with IR (2 Gy per fractions, 6 weeks, 5 days per week: total dose 60 Gy) at the doses of 25 and 50 mg/Kg. In the IR only arm, no tumor responses were observed. These effects were a likely consequence of inhibiting DNA-PK activity, as shown by measuring the autophosphorylation of DNA-PK in FaDu tumor tissue. M3814, alone or in combination with IR, did not induce significant weight loss or visual signs of toxicity in the mice in any study.[1]

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M3814 strongly enhanced the antitumor activity of ionizing radiation in vivo with complete tumor regression applying a clinically relevant fractionated radiation regimen. These effects are due to inhibition of DNA-PK protein kinase activity as demonstrated by the levels of DNA-PK autophosphorylation in human tumor cell lines, and xenograft tumors M3814 is currently investigated in PhI clinical trials [2].

The efficacy of M3814 in combination with IR was evaluated in 6 human xenograft models (HCT116, FaDu, NCI-H460, A549, Capan-1, BxPC3) in mice representing 4 different cancer types (colon, head and neck, lung, and pancreas). Tumor cells were injected s.c. into nude mice, and treatment started when palpable tumors were established (w100-200 mm3 ). M3814 was given orally at different doses (25-300 mg/kg) 10 min prior to IR. IR was applied using a radiation therapy device for small rodents calibrated to deliver 2 Gy. Autophosphorylation of DNA-PK (serine2056 ) in FaDu tumor lysates was measured by immunoassay to assess pharmacological inhibition by M3814.[1]

[1]. M3814, a DNA-dependent Protein Kinase Inhibitor"n(DNA-PKi), Potentiates the Effect of Ionizing Radiation (IR) in"nXenotransplanted Tumors in Nude Mice. IJROBP. 2016; 94, 940-941.

[2]. Abstract 1658: M3814, a novel investigational DNA-PK"ninhibitor: enhancing the effect of fractionated radiotherapy leading to"ncomplete regression of tumors in mice. AACR; Cancer Res 2016;76(14"nSuppl):Abstract nr 1658.

[3]. Arylchinazoline. WO2014183850A1.

Nedisertib is being investigated in the clinical trial NCT03770689 (M3814 in combination with capecitabine and radiotherapy for rectal cancer). Peposertib is an orally bioavailable DNA-dependent protein kinase (DNA-PK) inhibitor with potential antitumor activity and the potential to enhance the efficacy of chemotherapy and radiotherapy. After administration, Peposertib binds to and inhibits the activity of DNA-PK, thereby interfering with the non-homologous end joining (NHEJ) process and preventing the repair of DNA double-strand breaks (DSBs) induced by ionizing radiation or chemotherapy. This enhances the cytotoxicity of chemotherapy and radiotherapy and leads to increased tumor cell death. The enhanced ability of tumor cells to repair DSBs is a major cause of tumor cell resistance to chemotherapy and radiotherapy; DNA-PK plays a key role in the NHEJ pathway and DSB repair. M3814 has shown activity in combination with ionizing radiation in non-clinical trials. Strong antitumor activity was observed in several xenograft models. In the FaDu model (squamous cell carcinoma of the head and neck), the tumor completely regressed after an established clinical ionizing radiation regimen (2 Gy/session for 6 weeks). Clinical evaluation of M3814 is underway. [1] Physical or chemical factors such as ionizing radiation are among the most widely used cancer treatments. Radiation-induced double-strand breaks (DSBs) in DNA can induce a variety of cellular responses, including DNA repair, cell cycle arrest, or cell death if the damage is not repaired. DNA repair involves a series of complex molecular events, which are mainly carried out through two mechanisms: homologous recombination (HR) or non-homologous end joining (NHEJ). DNA-PKcs and their regulatory protein subunits Ku70 and Ku80 are important components of NHEJ and are considered ideal targets for inhibiting DNA repair. We have developed an orally bioavailable, highly effective and selective DNA-PK inhibitor, M3814, for cancer treatment, which can be used in combination with DNA damage therapies such as radiotherapy and chemoradiotherapy. This article describes our preclinical characterization of M3814 using biochemical, cytological, and human tumor xenograft models. [2]

C24H21CLFN5O3

481.9066

481.131

C, 59.82; H, 4.39; Cl, 7.36; F, 3.94; N, 14.53; O, 9.96

1637542-33-6

1637542-33-6 (S-isomer); 1637542-34-7 (racemate); 1637542-32-5 (R-isomer)

86292849

Light yellow to yellow solid powder

2.8

1

9

5

34

662

1

ClC1C=C(C(=CC=1[C@@H](C1C=CC(=NN=1)OC)O)C1C2C=CC(=CC=2N=CN=1)N1CCOCC1)F

MOWXJLUYGFNTAL-DEOSSOPVSA-N

InChI=1S/C24H21ClFN5O3/c1-33-22-5-4-20(29-30-22)24(32)16-11-17(19(26)12-18(16)25)23-15-3-2-14(10-21(15)27-13-28-23)31-6-8-34-9-7-31/h2-5,10-13,24,32H,6-9H2,1H3/t24-/m0/s1

(S)-(2-chloro-4-fluoro-5-(7-morpholinoquinazolin-4-yl)phenyl)(6-methoxypyridazin-3-yl)methanol

MSC2490484A; MSC-2490484A; nedisertib; peposertib; 1637542-33-6; M3814; M-3814; MSC-2490484-A; Nedisertib [INN]; M-3814(nedisertib); MSC 2490484A; M3814; M-3814; M 3814

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: (1). This product requires protection from light (avoid light exposure) during transportation and storage.  (2). Please store this product in a sealed and protected environment (e.g. under nitrogen), 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: ~50 mg/mL (~103.8 mM; with ultrasonication)

Solubility in Formulation 1: 5.56 mg/mL (11.54 mM) in 1% CMC-Na/5% Tween-80 in Saline water (add these co-solvents sequentially from left to right, and one by one), Suspended solution; with ultrasonication.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (5.19 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween-80 + 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 DMSO stock solution (25.0 mg/mL) to 400 μL of PEG300 and mix well; then add 50 μL of Tween-80 and mix well; finally add 450 μL of physiological saline and 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.

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