|Year : 1994 | Volume
| Issue : 1 | Page : 5-7
Influence of liposomal drug entrapment on the performance of corticosteroid creams
GU Rao, RSR Murthy, YS Marfatia, Rajesh Shankar
G U Rao
Source of Support: None, Conflict of Interest: None
Skin blanching and clinical efficacy of a liposomally entrapped Triamcinolone acetonide (TRMA) cream was compared with that of the conventional TRMA cream in healthy human volunteers and eczema patients respectively. Both the creams showed equal efficacy in eczema patients. A significant reduction in the skin blanching response with the liposomal TRMA cream as compared to the conventional TRMA cream suggests a decrease in the systemic absorption of the corticosteroid with the former.
Keywords: Liposomes, TRMA, Skin blanching, Clinical profile
|How to cite this article:|
Rao G U, Murthy R, Marfatia Y S, Shankar R. Influence of liposomal drug entrapment on the performance of corticosteroid creams. Indian J Dermatol Venereol Leprol 1994;60:5-7
|How to cite this URL:|
Rao G U, Murthy R, Marfatia Y S, Shankar R. Influence of liposomal drug entrapment on the performance of corticosteroid creams. Indian J Dermatol Venereol Leprol [serial online] 1994 [cited 2021 Jan 20];60:5-7. Available from: https://www.ijdvl.com/text.asp?1994/60/1/5/3971
| Introduction|| |
Prolonged topical application of corticosteroids in dermatitis, psoriasis and other dermatosis is known to cause unintended systemic side effects due to the percutaneous absorption of the drug. A new approach to achieve selective drug delivery to the skin is the use of liposomes as drug localizers.  Liposomes are microscopic vesicles composed of phospholipid bilayers which form spontaneously when appropriate composition of phospholipids are hydrated in aqueous media . 
Encapsulation of TRMA into liposomes favourably alters the drug disposition in rabbits with lower TRMA levels in the blood stream as compared to conventional TRMA cream. 
In the present study, the liposomal TRMA cream was compared with the conventional TRMA cream with respect to its skin blanching potential in healthy human volunteers and its efficacy in eczema patients.
| Materials and Methods|| |
TRMA liposomes were prepared by Bangham's lipid film rehydration method  using TRMA : lecithin : cholesterol in the ratio of 69ÁM : 190ÁM VI: 93ÁM. A 0.1% w/ w liposoinal TRMA cream was prepared by incorporating the drug loaded liposomes into aqueous cream base BPC. A conventional 0.1% w/w TRMA cream was prepared in the same base.
A double blind, occluded, skin blanching assay was conducted on forearms of 13 healthy human volunteers of either sex, using 10▒ 1 mg of the prepared creams. Skin blanching score was assigned after six.hours of application by an unbiased observor using a 0-4 scale rating based on the Barry Woodford's method .  The blanching scores for the two creams were subjected to a two tailed t-test to study the level of significance.
A double blind clinical trial was conducted at the Skin and VD Department of Shri Sayaji General Hospital, Baroda, on 10 patients with dry bilateral eczema for 1 month, with weekly assessments by clinical experts.
| Results|| |
The blanching scores for all the volunteers, for each formulation, were summed up and expressed as the percentage of the total possible score (%TPS). The histogram [Figure - 1] shows a statistically significant (p<0.001) decrease in the %TPS with the liposomal TRMA cream as compared to the conventional TRIVIA cream suggesting a decrease in the skin blanching response elicited by the former.
The [Table - 1] shows the results of the clinical trials. No statistically significant difference was observed in the clinical efficacy of the two creams in eczema patients.
| Comments|| |
The human skin blanching assay is an excellent model in evaluating the efficacy of topical corticosteroids prior to clinical trials.  When corticosteroids from topically applied dosage forms penetrate to the blood vessels of the skin, they cause vasoconstriction of the same and hence the skin gets blanched.
Reduction in skin blanching without adverse effects on the efficacy by the liposomal TRMA cream suggests the following
(i) incorporation of drug into liposomes limits the drug from reaching the blood stream. The lecithin of the liposomes probably increases the total lipid content of the stratum corneum which leads to formation of a steroid depot in this region from where a controlled delivery of the steroid to the lower skin layers, where blanching takes place, occurs. Hence the use of liposomal cream may reduce the systemic side effects.
(ii) Liposomally entrapped drug, localizes in the epidermis-dermis. Hence the dose of the drug can be reduced making the therapy cost effective.
| References|| |
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|2.||Tyrrell DA, Heath JD, Colley CM, et al. New aspects of Liposomes. Biochim Biophys Acta 1976 ; 457: 259-302. |
|3.||Mezei M, Gulosekharan V. Liposomes- A selective drug delivery system for the topical route of administration. Life Sci 1980; 26: 1473-7. |
|4.||Bangham AD, Hill M W, Miller NGA. Methods in Membrane Biol ( Korn D, ed ), New York : Plenum Press, 1974; 1-68. |
|5.||Barry B W, Woodford R. Comparative bioavailability of proprietar; topical corticosteroid preparations. Br J Dermatol 1974; 91 : 323-38. |
|6.||Haigh JM, Kanfer I. Assessment of topical corticosteroid preparations : the human skin blanching assay. Int J Pharm 1984; 19: 245-62. |
[Figure - 1]
[Table - 1]