Efficacy of a cosmetic product mimicking PRP in androgenetic alopecia

Abstract

Introduction: Androgenetic alopecia (AGA) is the most common hair loss disorder. Recently, platelet-rich plasma (PRP) injections have emerged as alternative
cell-based therapies for the treatment of AGA. Its efficacy is strictly linked to the release of growth factors (GFs) via alpha-granules degranulation. Among their
well-known activity, more recently, GFs are acquiring importance as regards their involvement in the regulation of hair growth cycle. Thanks to the advent of
modern biotechnology synthetic polypeptides mimicking growth factors have been developed opening to new therapeutic approaches also in the dermatological field,
including hair growth disorder.
Objective: The aim of the present study was to evaluate the efficacy of a cosmetic product (TR-M-PRP plus) mimicking PRP composition by means of biomimetic
peptides in subjects affected by AGA.
Materials and methods: 60 AGA subjects were treated for three months end evaluated, at the end of the study and after one month of follow-up, as regards hair
growth by evaluating total and anagen hair count, anagen/telogen ratio, % of miniaturization, Hair Mass Index (HMI), and hair shaft diameter.
Results: TR-M-PRP plus treatment produced a statistically significant (p < 0.001) clinical improvement compared with PLACEBO in total and anagen hair counts.
The treatment with TR-M-PRP plus resulted in a time- increased improvement in the anagen/telogen ratio, reduction of 5 of miniaturization and increasing of HMI
and Hair shaft diameter.
Conclusions: Our study confirms, for the first time, the clinical efficacy of a cosmetic product containing biomimetics peptides (TR-M-PRP plus) mimicking
autologous PRP for the treatment of AGA.

Full text

Journal of Cosmetic Dermatology ORIGINAL CONTRIBUTION
Efficacy of a cosmetic product mimicking PRP in Androgenetic Alopecia
Rinaldi Fabio
1*
,Marzani Barbara
1
, Pinto Daniela
1
, Sorbellini Elisabetta
1
1
International Hair Research Foundation, Milan, Italy
* Correspondence: fabio.rinaldi@studiorinaldi.com; Tel.: +39-2-76006089
Summary:
Introduction: Androgenetic alopecia (AGA) is the most common hair loss disorder. Recently,
platelet-rich plasma (PRP) injections have emerged as alternative cell-based therapies for the
treatment of AGA. Its efficacy is strictly linked to the release of growth factors (GFs) via
alpha-granules degranulation. Among their well-known activity, more recently, GFs are
acquiring importance as regards their involvement in the regulation of hair growth cycle.
Thanks to the advent of modern biotechnology synthetic polypeptides mimicking growth
factors have been developed opening to new therapeutic approaches also in the dermatological
field, including hair growth disorder.
Objective:
The aim of the present study was to evaluate the efficacy of
a cosmetic product
(TR-M-PRP plus) mimicking PRP composition by means of biomimetic peptides in subjects
affected by AGA.
Materials and Methods: 60 AGA subjects were treated for three months end evaluated, at the
end of the study and after one month of follow-up, as regards hair growth by evaluating total
and anagen hair count, anagen/telogen ratio, % of miniaturization, Hair Mass Index (HMI), and
hair shaft diameter.
Results: TR-M-PRP plus treatment produced a statistically significant (p < 0.001) clinical
improvement compared with PLACEBO in total and anagen hair counts. The treatment with
TR-M-PRP plus resulted in a time- increased improvement in the anagen/telogen ratio,
reduction of 5 of miniaturization and increasing of HMI and Hair shaft diameter.
Conclusions: Our study confirms, for the first time, the clinical efficacy of a cosmetic product
containing biomimetics peptides (
TR-M-PRP plus)
mimicking autologous PRP for the
treatment of AGA.

2
Keywords: PRP- Biomimetic Peptides – hair loss – AGA
1. Introduction
Hair loss disorders show high rates of occurrence in men and women. Androgenetic alopecia
(AGA) is the most common hair loss disorder, affecting up to 80% of men and 50% of women
in the course of their life
1-3
.AGA is characterized by a progressive reduction in the hair shaft
diameter, length, and pigmentation (miniaturization process). The pathogenesis of AGA is
complex with genetic, hormonal, inflammatory, and vascular factors thought to contribute to
the onset and progression
1,4-7
.
The prevalence of hair loss in the population and its impact on self-esteem and depression
8,9
,
therapies target to reduce the appearance of thinning by delaying, arresting, or reversing the
underlying pathology are highly desirable. Nowadays, the currently approved
pharmacotherapies are limited to oral Finasteride, a selective 5-α-reductase inhibitor, and 2%
or 5% topical Minoxidil solutions or foams
10
neither of which without side effects and
inevitably relapse in hair loss when the treatment is halted.
Alternative cell-based therapies for the treatment of AGA have emerged, of which,
platelet-rich plasma (PRP) injections appear particularly effective
11,12
.
PRP is an autologous product obtained by centrifugation from patients own venous blood with
no risk of disease transmission and with a concentration of platelets 4-7 time more than
baseline values
13
.
The autologous PRP was first used in 1987 by Ferrari et al.
14
to avoid excessive transfusion of
homologous blood products after open heart surgery. Since that time, the application of
autologous PRP has been safely used and documented in many application fields, such as
orthopedics and sports medicine, dentistry, neurosurgery, ophthalmology, urology, and wound
healing
15,16
.
The rationale of PRP therapy is that an injection of concentrated PRP at sites of injury may
affect tissue healing via growth factors released after platelets degranulation
17
. Most abundant
growth factors (GFs) are platelet-derived growth factor (PDGF), vascular endothelial growth

3
factor (VEGF), transforming growth factor-β (TGF-β), basic fibroblast growth factor (BFGF),
epidermal growth factor (EGF), and insulin-like growth factor (IGF). GFs have an important
role in cell proliferation, migration, and differentiation
17
.
The meta-analysis by Giordano et al.
18
encompassing a total of 194 patients (6 studies)
provides compelling evidence about PRP treatment for hair restoration in investigated for
AA
11,19,20
even if the majority of research targeted AGA
21,22
.
A significantly increased number of hairs per cm
2
was observed after treatment with PRP.
Furthermore, although the limited number of patients, they found interesting results also in hair
cross-section thickness and other secondary outcomes which showed a trend toward benefit.
Anyway, because there is no standardized method for PRP preparation, some differences in
product composition might be present. This fact may lead to an altered PRP function, which
might explain the controversy found in the literature. Furthermore, differences in PRP
composition result from differences in the samples retrieved from person to person. The used
end product may vary also by the used volume and the number of injections administered, as
well as platelet count, the number or absence of leukocytes, and its protein content
18
.
Lately, the use of cosmetic formulation containing biological active ingredients, such as
biomimetic peptides, has started to spread not only in consumer skin care but also in the
dermatological field.
The aim of this double-blind clinical study was to evaluate the efficacy of a cosmetic product
(TR-M-PRP plus)
23
mimicking PRP composition and GFs concentration by means of
biomimetic peptides in subjects affected by AGA.
2. Materials and methods
2.1 Subjects
A total of 60 subjects were enrolled in this a monocentric randomized study 2 arms of 2 parallel
groups (1:1 / 1:1 each) double-blinded placebo-controlled study. The study was conducted
under the approval of the Ethical Independent Committee for Clinical, not pharmacological
investigation in Genoa (Italy) and in accordance with the ethical standards of the 1964
Declaration of Helsinki.

4
2.2 Inclusion and exclusion criteria
Before inclusion, subjects were asked to sign an informed consent form indicating that they are
aware of the investigational nature of the study.
Participants to the study were healthy male and female subjects aged 18–60 years suffering
from AGA (II-IV Hamilton scale for men and I-II Ludwig scale for women) accepting to not
receive any drugs/cosmetics treatment able to interfere with the study results, no participation
in a similar study actually or during the previous 6 months.
Exclusion criteria included: known sensitivity to any compound of the Investigational product,
pregnant or breastfeeding females or planning a pregnancy, serious intercurrent infection or
other active disease up to three months prior to study entry, history of concurrent malignancy,
significant concurrent medical disorders that may impair the subject’s ability to participate
over the whole one year of the study.
2.3 Test product
Subjects were randomized to receive the study product (TR-M-PRP plus, Giuliani SpA, Milan)
containing biomimetic peptides - octapeptide-2, copper tripeptide-1, Oligopeptide-20, acetyl
decapeptide-3 -; lactoferrin; lactoglobulin; melatonin; humectant; preservative; viscosity
control) or PLACEBO (same formulation without biomimetic peptides, lactoferrin,
lactoglobulin, and melatonin).
Subjects were asked to apply 15 ml of TR-M-PRP plus /week (application time at least 5 h) or
PLACEBO for 3 months.
2.4 Evaluations
Evaluations were performed at the Baseline Visit (T0) and at the End of Treatment Visit (T1),
and at the Follow Up Visit (T2). The TrichoScan software (Trichology GmbH, Freiburg,
Germany) was employed for the analysis of following hair measurements: total hair count (in a
1cm2 area), anagen hair count and anagen/telogen ratio and miniaturization. Hair Mass Index

5
(HMI) was assessed by HairCheck® measuring system (Divi International Co., Miami, FL,
USA)
24,25
.
The Hair check cartridge was first calibrated and then placed in the J-slot and HMI measured.
Epiluminescence microscopy (Molemax HD, DermaInstrument, Vienna, Austria) was used for
determination of hair shaft diameter (mm). At the end of the study (T1) and at the Follow Up
Visit (T2), each subject was asked to fill a questionnaire regarding the efficacy of the study
treatment on daily hair loss, volume, on hair general aspect (hair thicker and stronger), on hair
growth speed and the product tolerance (score: negative, medium, good, excellent).
2.5 Statistical analysis
Comparisons between two individual visits were performed by means of two-sample-t-test.
P-values less than 0.05 were considered clinically significant.
3. Results
A total of 60 subjects (32 men and 28 women; women) were enrolled and received treatment
(Table 1).
Table 1 Baseline characteristics of subjects randomized
TR-M-PRP plus (n=30) PLACEBO (n=30)
Age (mean±SE) 39.42±3.96 31.84±1.80
Baseline hair count (mean±SD)
a
Total hair count 194.27±4.0 199.25±3.00
Anagen 129.2±5.0 120.85±2.95
% Anagen 66.51±4.0 60.65±4.75
Anagen/telogen ratio 1.98±0.2 1.54±0.15
Miniaturization (%) 48.34±3.0 50.97±3.13
Hair Mass Index (HMI) 1.98±0.2 1.54±0.15
Hair shaft diameter (mm) 0.51±0.1 0.57±0.06
a
Measured in a 1-
cm2
circle.

6
The two groups were generally similar in terms of baseline characteristics.
As determined by Trichoscan digital image analysis, after 3 months of treatment (T1)
TR-M-PRP plus produced a mean increase of 15.3 hairs (T0 TR-M-PRP plus vs T1 TR-M-PRP
plus: p<0,0001), while PLACEBO produced a decrease of 11.1 hairs (Table 2).
Table 2 Hair count data (mean±SD)
a
Telogen hair count= (Total hair count)-(Anagen hair count).
b
Anagen/telogen ratio=mean (anagen hair
count/telogen hair count).
TR-M-PRP plus efficacy was more evident at follow-up examination (+25.2; T0 TR-M-PRP
plus vs T2 TR-M-PRP plus: p<0,0001); no significative changes between T1 and T2 were
reported in the PLACEBO group.
TR-M-PRP plus treatment also led to a progressive increase in mean anagen hair count over 3
months (p<0,0001, Table 2). A further significative increase was also reported at the follow-up
examination (p<0,0001, Table 2). On the contrary treatment with PLACEBO led to a decrease
in mean anagen hair count (p<0,0001, Table 2).
TR-M-PRP plus treatment led to a statistically significant improvement of anagen/telogen ratio
after 3 months of treatment which resulted in further incremented at follow-up examination
(p<0,0001, Table 2). Also in this evaluation, a decrease was reported in the PLACEBO group
(p<0,00)
TR-M-PRP plus (n=30) PLACEBO (n=30)
Baseline
(T0)
T1 T2 Baseline
(T0)
T1
T2
Total hair count
194.3±4.0
204.2±3.2
219.5±3.3
199.3±3.0
188.3±3.3
187.30±3.4
Anagen hair
count
129.2±5.0
142.5±2.8
162.6±2.9
120.8±2.9
110.3±3.9
116.5±3.55
Telogen hair
count
a
65.1±4.45
61.6±2.6 56.8±2.5 78.4±3.8 77.9±3.9 70.80±3.45
Anagen/telogen
ratio
b
1.9±0.2 2.3±0.24 2.9±0.2 1.5±0.1 1.4±0.3 1.64±0.16

7
FIGURE 1 % of hair miniaturization as measured by TrichoScan software. Data
(miniaturization %) are expressed as mean ± SD of 30 subjects for the group, at baseline (T0),
after 3 months of treatment (T1) and at follow-up (T2). **= p<0.01; ****= p<0.001.
Figure 1 reported data on the percentage of miniaturization for TR-M-PRP plus and
PLACEBO group, respectively. We noticed a significative decrease in hair miniaturization %
in TR-M-PRP plus after 3 months of treatment compared to the PLACEBO group (40.40±1.85
vs 49.58±2.74) (p<0,0001). The effect derived from TR-M-PRP plus treatment is more evident
at follow-up examination (23.61±1.85 vs 49.27±2.72) (p<0,0001).

8
FIGURE 2 Hair Mass Index (HMI) as measured by HairCheck® measuring system. Data
(density score) are expressed as mean ± SD of 30 subjects for the group, at baseline (T0), after
3 months of treatment (T1) and at follow-up (T2). ****= p<0.001.
Following treatment with TR-M-PRP plus (Figure 2) HMI was significantly increased (162.27
± 4.57 to 187.90 ± 6.07; p<0.0001) and the effect maintained at follow up (198.17 ± 6.05; T2 vs
T1: p<0.0001) (Figure 2). This increase was statistically significant when compared with
PLACEBO group (T1 TR-M-PRP plus vs T1 PLACEBO: p<0,0001; T2 TR-M-PRP plus vs T2
PLACEBO: p<0,0001). In PLACEBO group no significative change was reported.
4. Discussion
AGA is the most reported form of hair loss
26
which main symptoms include miniaturization of
the hair follicle
27,28
. Also, hair growth cycle is altered in AGA subjects
29
. Current research is
highlighting the regulatory role of many substances, especially growth factors, on the hair
follicle cycle
30
.
Growing interest is focused on polypeptide growth factors. They can target many physiological
processes such as cell proliferation, protein synthesis, inflammation and pigmentation
31
.
More recently, polypeptide growth factors involved in the regulation of hair growth cycle have
been established
32,33
. Thanks to the advent of modern biotechnology polypeptides mimicking
growth factors have been developed
34
, opening to new therapeutic approaches also in the
dermatological field, including hair growth disorder.
The aim of the present work was to show the efficacy of TR-M-PRP plus, a cosmetic product
mimicking autologous PRP composition in term of growth factors on subjects affected by
AGA.
Efficacy of treatment with autologous PRP has largely been demonstrated both in AA
11,19
(and
AGA
21,22
subjects. More recently we published a work on the efficacy of TR-M-PRP plus in
the treatment of AA
23
.

9
In the present work, we tested the same cosmetic formulation on AGA subjects. The results
show significant changes in the objective parameters which were tested to evaluate the
effectiveness of the treatment.
TR-M-PRP plus treatment increased the amount and percentage of anagen hair progressively
from baseline over 3 months of treatments and at follow-up examination. Also, a progressive
increase of anagen/telogen ratio has been reported. On the opposite, in PLACEBO-treated
group anagen hair diminished during the study, consistent with follicular miniaturization.
The efficacy of the treatment on the promotion of anagen phase was further validated by a
significant decrease of follicular miniaturization and the increase both of HMI and Hair shaft
diameter. Therefore, all investigated subjects reported a good tolerance of the treatment and no
side effects. This is in line with recent evidence on the stability and safety of biomimetic
polypeptides
38
.
The above-reported efficacy of TR-M-PRP plus could be ascribed to the effect of biomimetic
peptides used (octapeptide-2, copper tripeptide-1, Oligopeptide-20, acetyl decapeptide-3) on
cell proliferation stimulation. Treatment efficacy is further enhanced by the anti-inflammatory
effect exerted by lactoferrin
35
, enhancing of cellular energy by lactoglobulin
36
and
clock-regulatory activity of melatonin
37
.
Taking together, our data strongly suggest that the treatment with a cosmetic product
mimicking autologous PRP, via biomimetic polypeptides, actively increases growing anagen
hair.
Conclusion
In conclusion, our study confirms, for the first time, the clinical efficacy of a cosmetic product
containing biomimetics peptides (TR-M-PRP plus) mimicking autologous PRP for the
treatment of AGA. Treatment result has well tolerated and no adverse events were reported.
Disclosure statement

10
R.F. and S.E. serve as a consultant for Giuliani S.p.A. P.D. and M.B. are employed by Giuliani
S.p.A.
Funding
This study was supported by the Giuliani SpA.
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