Halcinonide acts as a glucocorticoid receptor agonist. By binding to and activating the glucocorticoid receptor, it modulates gene expression, leading to the suppression of cytokine production and immune responses in the skin. It also binds to Smoothened (Smo) and promotes its internalization and expression, thereby activating the Hedgehog signaling pathway and Gli transcription factors. The precise anti-inflammatory mechanism of topical corticosteroids is not fully understood.

In vitro, halcinonide demonstrates potent glucocorticoid receptor agonistic activity. It has been shown to bind with significant affinity to glucocorticoid receptors. The compound's vasoconstrictive potency can be assessed using skin blanching assays. Halcinonide also activates the Hedgehog signaling pathway by binding to Smo and promoting its internalization, which stimulates cell proliferation.

In vivo, halcinonide (0.1% w/w) inhibits croton oil-induced ear edema by 70.1% and homologous passive cutaneous anaphylaxis (PCA) by 88.0% in rats when dosed three hours. It interacts with hormone receptors in the cytoplasm, eliciting anti-inflammatory effects. The compound is employed in the treatment of certain skin disorders. Various laboratory methods, including vasoconstrictor assays, are used to compare and predict the potencies and clinical efficacies of topical corticosteroids.

Cell-free receptor binding assays for halcinonide involve assessing its affinity for the glucocorticoid receptor. These assays typically use radiolabeled ligands (e.g., [³H]-dexamethasone) and membrane preparations from cells expressing the glucocorticoid receptor. Halcinonide is incubated with the receptor and radioligand, and competition binding is measured. The binding affinity (Kᵢ or IC₅₀) is calculated from displacement curves. Additionally, binding to Smo can be assessed using similar approaches.

In vitro cellular assays for halcinonide typically use cell lines expressing the glucocorticoid receptor. Cells are treated with halcinonide at various concentrations, and the activation of glucocorticoid-responsive reporter genes is measured. The compound's ability to suppress cytokine production can be assessed by stimulating cells with inflammatory agents (e.g., LPS) in the presence of halcinonide and measuring cytokine levels by ELISA. Cell proliferation assays can be used to evaluate the effects of Hedgehog pathway activation.

In vivo animal studies for halcinonide commonly use the croton oil-induced ear edema model in rats to assess anti-inflammatory activity. The compound is applied topically, and ear swelling is measured after a specified time. The passive cutaneous anaphylaxis (PCA) model is used to evaluate anti-allergic effects. Skin blanching assays in human volunteers are used to quantify corticosteroid-induced vasoconstriction. Different halcinonide concentrations (0.005% to 0.200%) are tested in these assays.

Halcinonide is a topical corticosteroid with potent anti-inflammatory activity. It has a molecular formula of C₂₄H₃₂ClFO₅ and a molecular weight of 454.96. The compound is typically formulated as a topical solution or ointment at 0.1% concentration for dermatological use. It is absorbed through the skin, and its systemic absorption can lead to corticosteroid-related side effects with prolonged use.

Halcinonide is an organic molecular entity whose mechanism of action is as an SMO receptor agonist. Halcinonide is a corticosteroid used to relieve inflammatory and itchy symptoms of corticosteroid-sensitive dermatitis, available in both cream and ointment formulations. Halcinonide is marketed by Ranbaxy Laboratories under the brand name Halog®. Studies have shown that clobetasol propionate has superior pharmacological efficacy in treating psoriasis compared to halcinonide. Halcinonide is a corticosteroid. Its mechanism of action is as a corticosteroid hormone receptor agonist. Halcinonide is a topical synthetic glucocorticoid with anti-inflammatory and anti-allergic properties. Halcinonide exerts its effects by interacting with specific intracellular receptors, and the ligand-receptor complex subsequently regulates gene expression through the typical glucocorticoid signaling pathway. This leads to the inhibition of the synthesis of certain anti-inflammatory proteins and certain inflammatory mediators. Therefore, chronic inflammation and autoimmune responses are reduced overall. (NCI05)
A topical corticosteroid used to treat dermatitis, eczema, or psoriasis. It may cause skin irritation.
Indications

For the relief of inflammatory and itchy symptoms in skin conditions sensitive to corticosteroids.
FDA Label
Mechanism of Action

The exact mechanism of action of topical corticosteroids is not fully understood. However, they have anti-inflammatory, antipruritic, and vasoconstrictive effects. Recent research suggests that halcinonide can promote the expression of myelin basic protein (MBP) by activating the Smoothened receptor. This finding suggests that halcinonide may be a promising alternative to dexamethasone or methylprednisolone in the treatment of multiple sclerosis.
Halcinonide was developed as SQ-18566. It is a high-potency corticosteroid, and its strength necessitates careful medical supervision and limited treatment duration. The compound is used as a reference standard in analytical methods for the identification of corticosteroids, and it can be detected in real samples using HPLC and LC/MS. It is for research use only and not for therapeutic use.

C24H32CLFO5

454.9634

454.192

3093-35-4

443943

Typically exists as solid at room temperature

1.3±0.1 g/cm3

564.3±50.0 °C at 760 mmHg

276-277

295.1±30.1 °C

0.0±3.5 mmHg at 25°C

1.567

3.31

1

6

2

31

887

8

C[C@@]12[C@@]3(C(CCl)=O)[C@@](OC(C)(O3)C)([H])C[C@@]1([H])[C@]4([H])CCC5=CC(CC[C@]5(C)[C@@]4(F)[C@@H](O)C2)=O

MUQNGPZZQDCDFT-JNQJZLCISA-N

InChI=1S/C24H32ClFO5/c1-20(2)30-19-10-16-15-6-5-13-9-14(27)7-8-21(13,3)23(15,26)17(28)11-22(16,4)24(19,31-20)18(29)12-25/h9,15-17,19,28H,5-8,10-12H2,1-4H3/t15-,16-,17-,19+,21-,22-,23-,24+/m0/s1

(1S,2S,4R,8S,9S,11S,12R,13S)-8-(2-chloroacetyl)-12-fluoro-11-hydroxy-6,6,9,13-tetramethyl-5,7-dioxapentacyclo[10.8.0.02,9.04,8.013,18]icos-17-en-16-one

SQ-18566; Halog; Halcinonide

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)

DMSO : ≥ 48 mg/mL (~105.50 mM)

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.)