VEGF receptors

Researchers have evaluated a small cyclic retro-inverted peptidomimetic, D(Cys-Leu-Pro-Arg-Cys) [D(CLPRC)], and hereafter named Vasotide, that inhibits retinal angiogenesis by binding selectively to the VEGF receptors VEGFR-1 and neuropilin-1 (NRP-1). [1]

Vasotide reduces vascular tuft formation in ROP mice.
Vasotide reduced angiogenesis in a laser-induced monkey model of AMD.
Vasotide administered i.p. reduced angiogenesis in the mouse vldlr model of RAP.
The VEGF receptor-targeted prototype peptidomimetic Vasotide can reduce pathological angiogenesis in two preclinical murine models and one non-human primate model of human retinal diseases: the mouse ROP model, the vldlr knockout mouse model of retinal angiogenesis proliferation (RAP), and the laser-induced monkey model of wet AMD. Each disease type displays both common and unique angiogenic features. This suggests that, like the currently FDA-approved anti-VEGF therapeutics, Vasotide may be valuable for a range of human retinal diseases involving angiogenesis. Indeed, our results with Vasotide are roughly similar to the therapeutic response to bevacizumab previously reported in eyes of animals of the same primate colony comparably lesioned by laser-induced photocoagulation. More elaborate pharmacokinetic/therapeutic analysis of Vasotide is required to identify additional characteristics such as duration of efficacy, safety, convenience and cost. [1]

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Delivery of Vasotide via either eye drops or intraperitoneal injection in a laser-induced monkey model of human wet AMD, a mouse genetic knockout model of the AMD subtype called retinal angiomatous proliferation (RAP), and a mouse oxygen-induced model of ROP decreased retinal angiogenesis in all three animal models. This prototype drug candidate is a promising new dual receptor inhibitor of the VEGF ligand with potential for translation into safer, less-invasive applications to combat pathological angiogenesis in retinal disorders. [1]

Eye drop administration of drugs to monkeys [1]
A topical formulation of the Vasotide peptide was administered at a concentration of 120 mg/ml. Following laser photocoagulation on day 1, the test article, Blink Gel Tears, referred to in this text as GelTears, was administered topically by pipette onto both right and left eyes (50 µl) twice daily for 5 days, then once daily for 16 days. The vehicle alone (50 µl) was delivered in an identical fashion. Treatment regimen was as defined in Table S1. Monkeys were dosed while in a supine position.

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Mouse vldlr-null (knockout) model of the human Retinal Angiomatous Proliferation (RAP) disorder [1]
Breeding pairs of mutant mice with targeted deletion of the vldlr gene (B6;129S7-Vldlrtm1Her/J; vldlr KO) were maintained and bred in standardized conditions. Age-matched C57BL/6J mice were used as normal wildtype controls. Vldlr KO mice were randomly divided into three groups: vldlr KO without treatment, vldlr KO given control peptide D(CAPAC), and vldlr KO given the therapeutic peptide Vasotide. We injected intraperitoneally (i.p.) 20 µg peptide/µl PBS, 40 µg/g body weight, daily at P12-P18, P48-P54, P108-P114 and P208-P214. Mice were maintained according to the Association for Research in Vision and Ophthalmology statement on animal usage in ophthalmic research.

[1]. The peptidomimetic Vasotide targets two retinal VEGF receptors and reduces pathological angiogenesis in murine and nonhuman primate models of retinal disease. Sci Transl Med . 2015 Oct 14;7(309):309ra165.
[2]. The potential of anti-VEGF (Vasotide) by eye drops to treat proliferative retinopathies. Ann Transl Med . 2016 Oct;4(Suppl 1):S41. d

A suggested new treatment for blinding retinal diseases This paper describes a novel small drug candidate named Vasotide™, made of engineered amino acids, that blocks abnormal overgrowth of blood vessels in the eye’s retina, leading to loss of vision. A distinctive feature of this drug is its delivery in simple eye drops. Vasotide uniquely prevents a blood vessel growth-promoting molecule called VEGF from attaching to two different receptor molecule types on endothelial cells, which line the inside of blood vessels, thereby inhibiting the pathology in animal models of major retinal diseases called aged macular degeneration, retinopathy of prematurity, and possibly the untested but similarly caused diabetic retinopathy. [1]

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Blood vessel growth from preexisting vessels (angiogenesis) underlies many severe diseases including major blinding retinal diseases such as retinopathy of prematurity (ROP) and aged macular degeneration (AMD). This observation has driven development of antibody inhibitors that block a central factor in AMD, vascular endothelial growth factor (VEGF), from binding to its receptors VEGFR-1 and mainly VEGFR-2. However, some patients are insensitive to current anti-VEGF drugs or develop resistance, and the required repeated intravitreal injection of these large molecules is costly and clinically problematic.[1]

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Collectively, the findings presented by Sidman and colleagues, indicate the potential of agents such as Vasotide, which inhibit VEGFR-1 and NRP-1 for the treatment of a variety of ocular diseases featuring neovascularization. Vasotide was not directly compared to current United States Food and Drug Administration (FDA)-approved agents such as aflibercept, ranibizumab and bevacizumab, which target VEGF-A and VEGFR-2. This assessment is important for not only understanding the relative efficacy of Vasotide, but also which components of the VEGF pathway are most critical for attenuating ocular neovascularization, findings that may be particularly relevant to patients resistant to current anti-VEGF agents. Perhaps one of the most promising aspects for the future treatment of ocular neovascularization and vascular permeability is topical administration. If penetrance to the retina and choroid can be confirmed and then optimized, and robust pharmacokinetic and safety data obtained, eye drops would be preferable to currently monthly intravitreal injections and may result in significant economic savings.[2]

C₂₇H₂₉CL₂N₇O₂S

586.54

Typically exists as solid at room temperature

O=C(NCC1=CC=C(S(C2=CC(F)=CC(F)=C2)(=O)=O)C=C1)C3=CN4C(C=C3)=NC=C4.Cl

Vasotide; D(Cys-Leu-Pro-Arg-Cys); D(CLPRC)

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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