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Thymuskin: Clinical Efficacy, Biological Effects, Modes of Action …
Tags: alopecia, baldness, biological effects, both genders, catagen, clinical efficacy, exploratory study, gkl, hair cycle, hair follicles, hair hair, hair roots, hairs, hormonal hair loss, hormone testosterone, loss of hair, metabolite, sex hormone, third decade, tonsure,Pages: 6
Language: english
Created: Wed Aug 23 11:19:26 2006
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Thymuskin:
Clinical Efficacy, Biological Effects, Modes of Action
Growth Cycle of Hair
Hair shedding in healthy humans amounts up to 100 hairs a day; the same number of
hairs grow anew. The hairs are formed in the hair roots (follicles) by keratinocytes.
Each hair has a growing (anagen) phase of 2-6 years followed by a resting (catagen)
phase of about 2 months and a (telogen) end-phase, during which the hair falls out.
Does the loss of hair exceed the re-growth rate the hair becomes thin (alopecia) and
finally baldness occurs.
Figure 1: Hair Cycle
The Efficacy of Thymuskin in Clinical Trials
In the three most frequent forms of hair loss Thymuskin has been shown to be
effective in clinical trials. These forms of hair loss which differ in their appearance,
course and causes are described below:
Congenital Hormonal Hair Loss or alopecia androgenetica
In men hair loss most commonly starts in the third decade at the front and temples
progresses to the vertex of the head forming a tonsure so that finally a wreath of hair
remains. In this type of hair loss Thymuskin proved to be effective in 73% of the
afflicted men in form of a new growth of hair or of a hold of hair loss (1).
In women the congenital form of hair loss occurs less frequently, in later age and in
different pattern namely more on the crown of the head. All women treated with
Thymuskin stated an improvement (1).
In both genders the cause of the congenital hair loss is an increased sensitivity of the
hair follicles against the sex hormone testosterone and its metabolite
dihydrotestosterone, respectively.
In an exploratory study with Thymuskin GKL 02 (2) a statistical significant reduction
in daily hair loss by 45 % (p=0.01) occurred in the 18 patients treated for
9 months; by 65% in females and 36% in males, respectively, as shown in figure 2.
The ratio of anagen/telogen phases of hair as determined in the trichogram increased
in 19 patients with complete data for 6 months from 5.88 to 10.46 (p=0.10) as shown
in figure 3.
-1-
Figure 2: Reduction in Daily Hair Loss under Thymuskin GKL 02
Number Subgroups Baseline 3 months 6 months 9 months T-test,2-sided Reduction
18 All 91 69 55 50 P=0.01 45.05%
5 Females 96 68 40 34 P=0.03 65.58%
13 Males 89 70 61 57 P=0.10 35.96%
Reduction in Hair Loss
100
90
80
70
60 Baseline
3 months
50 6 months
9 months
40
30
20
10
0
All Females Males
Diffuse Hair Loss or alopecia diffusa
In this form the hairs are thinning out rather uniformly on the entire scalp. Metabolic
or hormonal disturbances, infections, stress and medications (especially anti-cancer
drugs) may be the cause. In patients with breast and colon cancer under treatment
with medium strong cancer drugs concomitant application of Thymuskin prevented in
41-81% largely or completely the expected hair loss (3). In cases with diffuse hair
loss of other causes Thymuskin was effective in 73% (4).
Figure 3
Increase in anagen/telogen ratios in the trichograms
19 patients with complete data at 6 months
Scalp Baseline 6 months T-test 2sided
Frontal 4,09 9,83 P=0,22
Occipital 7,67 10,98 P=0,26
Combined 5,88 10,46 P=0,10
11
10
9
8
7
6
5
4
3
2
1
0
Frontal Occipital Combined
-2-
Circumscribed Hair Loss or alopecia areata
Immunological disturbances are suspected as the cause since T-lymphocytes which
play a role in the defense system of the body are attacking the hair follicles. An
inflammation occurs which impairs hair growth and finally leads to the loss of hair. In
this severe form of alopecia 65% of the patients treated with Thymuskin experienced
new hair growth at the scalp and/or body whereby in 40% of the cases a complete
remission occurred (5).
Action of Thymuskin in Experimental Models and Probable
Modes of Action
Biological activity
Thymuskin (development code GKL 02) is a synthetic peptide library identical to the
former hydrolyzed extract of bovine thymus. Since Thymuskin GKL 02 consists of
several components (various tetra peptides) it is difficult to clarify the mode of action
and to attribute it to single components. Most likely several components contribute to
the action. Though the clarification of the mode of action is desirable from a scientific
point of view it is secondary for the successful treatment of hair loss. However it has
been shown that Thymuskin exerts biological effects in various human cells, cultures
and on biological substrates such as enzymes. These effects could explain the
clinical efficacy of Thymuskin in the various forms of alopecia.
Figure 4:
Proliferation of human BL
2,5
Effect of Thymuskin GKL 02 on the proliferation
2,25
of human blood lymphocytes (PBL) 2
relative to control = 1
1,75
Substance Dose Effect Diff. vs contr. 1,5
Control 0 1 1,25
PHA 0,4 2,33 P