Topoisomerase II; Daunorubicins/Doxorubicins

Aldoxorubicin (INNO-206) (0.27 to 2.16 μM) inhibits the formation of blood vessels and decreases the growth of multiple myeloma cells in a pH-dependent fashion[1].

Aldoxorubicin (INNO-206) (10.8 mg/kg, i.v.) is well tolerated; 90% of mice with the LAGκ-1A tumor survive until the study's conclusion[1]. It also exhibits significantly smaller tumor volumes and IgG levels on day 28. Phase I studies have shown that aldoxorubicin (INNO-206) can cause tumor regressions in sarcoma, small cell lung cancer, and breast cancer while maintaining a good safety profile at doses up to 260 mg/mL doxorubicin equivalents[2]. In models of breast carcinoma xenografts and murine renal cell carcinoma, aldoxorubicin (INNO-206) exhibits better efficacy than doxorubicin[3].

Cell viability assay[1]
Cells were seeded at 1 × 105 cells/100 μL/well in 96-well plates in RPMI-1640 media with FBS for 24 hours before treatment. Cells were cultured in the presence of medium, INNO-206 or doxorubicin for 48 hours. Next, cell viability was quantified using the CellTiter 96 AQueous Non-Radioactive Cell Proliferation Assay (Promega). Each well was treated with MTS for 1 to 4 hours, after which absorbance at 490 nm was recorded using a 96-well plate reader. The quantity of formazan product as measured is directly proportional to the number of living cells. Data graphed are means ± SEM using 3 replicates per data point.
The anti–multiple myeloma effect of INNO-206 at different pH levels on multiple myeloma cell proliferation using multiple myeloma cell lines with the MTS assay and antiangiogenic activity using the chorioallantoic membrane/feather bud assay were determined. The anti–multiple myeloma effects and toxicity of INNO-206 were also compared with conventional doxorubicin and PEGylated liposomal doxorubicin (PLD) alone, and in combination with bortezomib, using our multiple myeloma xenograft models[1].

INNO-206 stock solutions (5.4 mg/mL) were prepared using 50% ethanol and 50% water and further diluted in sterile water [1]. For the LAGκ-1A experiment, INNO-206 was administered to SCID mice at 10.8 mg/kg (doxorubicin equivalent dose of 8.0 mg/kg) once weekly. Mice were treated with conventional doxorubicin at 4.0 and 8.0 mg/kg once weekly. For the LAGκ-2 experiment, INNO-206 was administered once weekly (W) at doses of 2.7 and 5.4 mg/kg, or on 3 consecutive days (W-F) weekly at doses of 0.9 and 1.8 mg/kg. Bortezomib was administered twice weekly (W, F) at a dose of 0.5 mg/kg. Doxorubicin was administered to SCID mice at 2, 4, and 8 mg/kg, and PLD was administered to SCID mice at 2 mg/kg once weekly. Each drug was administered i.v. in a volume of 100 μL.[1]

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The (6-maleimidocaproyl)hydrazone derivative of doxorubicin (INNO-206) is an albumin-binding prodrug of doxorubicin with acid-sensitive properties that is being assessed clinically. The prodrug binds rapidly to circulating serum albumin and releases doxorubicin selectively at the tumor site. This novel mechanism may provide enhanced antitumor activity of doxorubicin while improving the overall toxicity profile. Preclinically, INNO-206 has shown superior activity over doxorubicin in a murine renal cell carcinoma model and in breast carcinoma xenograft models. In this work, we compared the antitumor activity of INNO-206 and doxorubicin at their respective maximum tolerated doses in three additional xenograft models (breast carcinoma 3366, ovarian carcinoma A2780, and small cell lung cancer H209) as well as in an orthotopic pancreas carcinoma model (AsPC-1). INNO-206 showed more potent antitumor efficacy than free doxorubicin in all tumor models and is thus a promising clinical candidate for treating a broad range of solid tumors[3].

[1]. Anti-Myeloma Effects of the Novel Anthracycline Derivative INNO-206. Clin Cancer Res.2012 18; 3856.

[2]. INNO-206 (DOXO-EMCH), an Albumin-Binding Prodrug of Doxorubicin Under Development for Phase II Studies. Current Bioactive Compounds, 2011, 7(1): 33-38(6).

[3]. INNO-206, the (6-maleimidocaproyl hydrazone derivative of doxorubicin), shows superior antitumor efficacy compared to doxorubicin in different tumor xenograft models and in an orthotopic pancreas carcinoma model. Invest New Drugs. 2010 Feb;28(1):14-9.

[4]. Cell penetrating peptides fused to a thermally targeted biopolymer drug carrier improve the delivery and antitumor efficacy of an acid-sensitive doxorubicin derivative. Int J Pharm. 2012 Oct 15;436(1-2):825-32.

[5]. Hydrazone, Amide, Carbamate, Macromolecular and Other Prodrugs of Doxorubicin. The Open Drug Delivery Journal, 2008, 2, 77-85.

Aldoxorubicin, an antineoplastic agents, is an albumin-binding prodrug of doxorubicin.
Aldoxorubicin is a 6-maleimidocaproyl hydrazone derivative prodrug of the anthracycline antibiotic doxorubicin (DOXO-EMCH) with antineoplastic activity. Following intravenous administration, aldoxorubicin binds selectively to the cysteine-34 position of albumin via its maleimide moiety. Doxorubicin is released from the albumin carrier after cleavage of the acid-sensitive hydrazone linker within the acidic environment of tumors and, once located intracellularly, intercalates DNA, inhibits DNA synthesis, and induces apoptosis. Albumin tends to accumulate in solid tumors as a result of high metabolic turnover, rapid angiogenesis, hypervasculature, and impaired lymphatic drainage. Because of passive accumulation within tumors, this agent may improve the therapeutic effects of doxorubicin while minimizing systemic toxicity.

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Mechanism of Action INNO-206 is the (6-Maleimidocaproyl) hydrazone of doxorubicin. INNO-206 is a prodrug of doxorubicin that binds endogenous albumin after administration. The bound doxorubicin is released in the acidic environment of the tumor cell through cleavage of an acid sensitive linker. In preclinical models, INNO-206 was superior to doxorubicin with regard to antitumor efficacy and toxicity.

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Doxorubicin has shown efficacy especially in combination treatment for the treatment of multiple myeloma; however, its side effects limit its use. INNO-206 is an albumin-binding prodrug of doxorubicin, which is released from albumin under acidic conditions. Because INNO-206 has not been previously evaluated in any hematologic malignancy, we determined its anti–multiple myeloma effects. Experimental Design: The anti–multiple myeloma effect of INNO-206 at different pH levels on multiple myeloma cell proliferation using multiple myeloma cell lines with the MTS assay and antiangiogenic activity using the chorioallantoic membrane/feather bud assay were determined. The anti–multiple myeloma effects and toxicity of INNO-206 were also compared with conventional doxorubicin and PEGylated liposomal doxorubicin (PLD) alone, and in combination with bortezomib, using our multiple myeloma xenograft models. Results: INNO-206 inhibited blood vessel formation and reduced multiple myeloma cell growth in a pH-dependent fashion. INNO-206 alone produced marked anti–multiple myeloma effects in vivo at doses that doxorubicin was toxic, and the combination of INNO-206 plus bortezomib produced increased anti–multiple myeloma effects compared with either agent alone. In contrast, all mice receiving bortezomib with doxorubicin or PLD died. Conclusions: These findings show that INNO-206 produces anti–multiple myeloma effects in vitro and in vivo. It also enhances the antitumor effects of bortezomib. These results suggest that INNO-206 may provide patients with multiple myeloma with an anthracycline that may be administered safely at higher doses compared with free doxorubicin, resulting in superior efficacy compared with the currently available anthracyclines to treat this B-cell malignancy.[1] Clin Cancer Res; 18(14); 3856–67. ©2012 AACR.

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The (6-maleimidocaproyl)hydrazone derivative of doxorubicin (INNO-206, formerly DOXO-EMCH) is a prodrug of the anticancer agent doxorubicin which is selectively bound to the cysteine-34 position of endogenous albumin within a few minutes after intravenous administration planned for 2011. Preclinically as well as clinically, the albuminbound form of INNO-206 has a large AUC, a small volume of distribution and low clearance compared to doxorubicin, uptake in solid tumors being mediated by the pathophysiology of tumor tissue, characterized by angiogenesis, hypervasculature, a defective vascular architecture, and an impaired lymphatic drainage. The prodrug contains an acid-sensitive hydrazone linker allowing doxorubicin to be released either extracellularly in the slightly acidic environment often present in tumor tissue or intracellularly in acidic endosomal or lysosomal compartments after cellular uptake of the albumin conjugate by the tumor cell. INNO-206 shows significantly superior antitumor efficacy over free doxorubicin in a spectrum of preclinical tumor models. In a phase I study, INNO-206 showed a good safety profile at doses up to 260 mg/m2 doxorubicin equivalents. Although not the primary end point of the phase I study, INNO-206 was able to induce tumor regressions in breast cancer, small cell lung cancer and sarcoma. Phase II studies against gastric cancer, pancreatic cancer and sarcoma are planned for the end of 2010.[2]

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Elastin-like polypeptide (ELP) is a macromolecular carrier with thermally responsive properties that can passively accumulate in solid tumors and additionally aggregate in tumor tissue when exposed to hyperthermia. In this study, ELP was conjugated to the anticancer drug doxorubicin (DOXO) and three different cell penetrating peptides (CPP) in order to inhibit tumor growth in mice compared to free doxorubicin. Fluorescence microscopy studies in MCF-7 breast carcinoma cells demonstrated that the three different CPP-ELP-DOXO conjugates delivered doxorubicin to the cell nucleus. All CPP-ELP-DOXO conjugates showed cytotoxicity with IC(50) values in the range of 12-30 μM at 42 °C, but the ELP carrier with SynB1 as the cell penetrating peptide had the lowest intrinsic cytotoxicity. Therefore, the antitumor efficacy of SynB1-ELP-DOXO was compared to doxorubicin under hyperthermic conditions. C57BL/6 female mice bearing syngeneic E0771 murine breast tumors were treated with either free doxorubicin or the SynB1-ELP-DOXO conjugate with or without focused hyperthermia on the tumor. Under hyperthermic conditions, tumor inhibition with SynB1-ELP-DOXO was 2-fold higher than under therapy with free doxorubicin at the equivalent dose, and is thus a promising lead candidate for optimizing thermally responsive drug polymer conjugates.[4]

C37H43CLN4O13

787.209329843521

786.251

C, 56.45; H, 5.51; Cl, 4.50; N, 7.12; O, 26.42

480998-12-7

Aldoxorubicin;1361644-26-9;MC-DOXHZN;151038-96-9

10056071

Red solid powder

8

15

12

55

1510

6

Cl.O(C1CC(C(C(C)O1)O)N)C1C2C(=C3C(C4C(=CC=CC=4C(C3=C(C=2C[C@@](C(CO)=NNC(CCCCCN2C(C=CC2=O)=O)=O)(C1)O)O)=O)OC)=O)O

NGKHWQPYPXRQTM-UKFSEGPMSA-N

InChI=1S/C37H42N4O13.ClH/c1-17-32(46)20(38)13-27(53-17)54-22-15-37(51,23(16-42)39-40-24(43)9-4-3-5-12-41-25(44)10-11-26(41)45)14-19-29(22)36(50)31-30(34(19)48)33(47)18-7-6-8-21(52-2)28(18)35(31)49;/h6-8,10-11,17,20,22,27,32,42,46,48,50-51H,3-5,9,12-16,38H2,1-2H3,(H,40,43);1H/b39-23+;/t17-,20-,22-,27-,32+,37-;/m0./s1

N-[(E)-[1-[(2S,4S)-4-[(2R,4S,5S,6S)-4-amino-5-hydroxy-6-methyloxan-2-yl]oxy-2,5,12-trihydroxy-7-methoxy-6,11-dioxo-3,4-dihydro-1H-tetracen-2-yl]-2-hydroxyethylidene]amino]-6-(2,5-dioxopyrrol-1-yl)hexanamide;hydrochloride

INNO-206 HCl; MC-DOXHZN hydrochloride; INNO206; DOXO-EMCH; EMCH-Doxo; EMCH-doxorubicin; INNO-206; INNO 206; MC-DOXHZN HCl; INNO-206 hydrochloride; Aldoxorubicin?HCl; 1361563-03-2; Aldoxorubicin (hydrochloride); Aldoxorubicin Hydrochloride [USAN];Aldoxorubicin.

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 (e.g. under nitrogen), avoid exposure to moisture and light.

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

DMSO: ~25 mg/mL (~31.8 mM)
H2O: ~12.5 mg/mL (~15.9 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (2.64 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.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (2.64 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 20.8 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.

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