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Retinova / Renova
: Product Information
TRADE NAME:
Retinova (sold under trade name Renova in the US)
Licensed
Indications:
Retinova is licensed for: ‘the
topical treatment of mottled hyperpigmentation, roughness and
fine wrinkling of photodamaged skin due to chronic sun
exposure.’
Background Information
Cumulative damage to the skin,
due to Ultraviolet (UV) radiation from chronic sun exposure,
may result in visible clinical changes characterised as
photo-ageing (dermatoheliosis) or photodamage. These include
both fine and coarse wrinkling and a yellow, lax, rough,
telangiectatic and mottled hyperpigmentation of the skin.
These clinical changes are accompanied by characteristic
histologic changes such as epidermal dysplasia with cytologic
atypia, dermal damage with marked elastosis, loss of collagen,
increased melanocytic activity, loss of polarity of
keratinocytes, an increase in glycosaminoglycans and a modest
inflammatory infiltrate.1
Dosage and
administration
In adults and elderly patients,
tretinoin should be applied once daily, at night, in
sufficient quantities to lightly cover the affected areas.
Once the maximum beneficial effect has been achieved (3-6
months) it can be maintained by continuing to apply tretinoin
cream one to three times a week.
Clinical
Efficacy
The two largest trials,2,3
involved a total of over 600 healthy Caucasian subjects with
mild or moderate facial photodamage. In one study2 299 such
subjects were randomised to treatment with an emollient cream
formulation of tretinoin (TEC) 0.05% (n = 100), 0.01% (n =
100) or control vehicle (n = 99) applied once daily to the
face for 24 weeks. Thirty-six subjects withdrew from the study
including 12 subjects who withdrew due to an adverse skin
reaction. 86% and 61% of subjects showed a statistically
significant global improvement (graded by the investigator)
with 0.05% TEC (p < 0.001) and 0.01% TEC (p < 0.05)
respectively, compared with 44% of control subjects. Fine
wrinkling (p < 0.001); mottled hyperpigmentation (p <
0.001); roughness (p = 0.012) and laxity (p = 0.001) showed
significant improvement with 0.05% TEC compared with vehicle.
Eighty-seven percent of patients using 0.05% TEC judged their
skin to be improved relative to baseline compared with 43% of
the vehicle group.2
In the second study3 320 subjects
were randomised to treatment with TEC 0.05%, 0.01%, 0.001% or
control vehicle, with 80 patients in each treatment arm. The
treatment cream was applied to the entire face once each
evening for 24 weeks. A total of 24 patients withdrew from the
study including 4 subjects who withdrew due to an adverse skin
reaction. At 24 weeks, subjects receiving TEC 0.05% showed
significantly greater global improvement (p < 0.001) and
reduction in overall severity (p = 0.002) than those receiving
vehicle. Mottled hyperpigmentation, fine wrinkling and
roughness were decreased to a significantly greater extent
following treatment with TEC 0.05% compared with vehicle (p
< 0.05). Seventy-eight percent of patients using 0.05% TEC
judged the appearance and feel of their skin to be improved
relative to baseline compared with 70% of the 0.01% TEC group;
60% of the 0.001% TEC group and 61% of the vehicle
group.3
The histologic data from these
two studies2,3 were reported separately.4 A significantly
greater increase from baseline in epidermal thickness was seen
with 0.05% TEC (p < 0.001) and 0.01% TEC (£ 0.002) than
with vehicle-treated patients. A similar dose-dependent
increase in granular thickness was also found after therapy.
This increase was statistically significant between 0.05% TEC
and vehicle groups (p < 0.001) and 0.01% TEC and vehicle
groups (p £ 0.004).
The percentage of patients who
exhibited a compaction of the stratum corneum was
significantly greater with 0.05% TEC (p £ 0.002) and 0.01% TEC
(p £ 0.02) than with vehicle-treated patients. Melanin content
decreased significantly from baseline after 24 weeks of
therapy, declining to a significantly greater extent in the
0.05% TEC groups compared with the vehicle group (p =
0.017).4
The effect of longer term
treatment on hyperpigmentation was investigated in 60 healthy
white patients5 who were randomly assigned to receive either
tretinoin 0.1% (n = 30) or vehicle (n = 30) applied once
nightly to face, arms, forearms and backs of hands for ten
months. After ten months, a statistically significant
lightening of hyperpigmented facial and upper-extremity
lesions was demonstrated in 83% to 88% of patients in the
tretinoin group compared to 29% of patients in the vehicle
group (p < 0.002). Fifteen patients who had received
tretinoin went on to receive a further six months of either
continued tretinoin treatment (n = 8) or vehicle (n = 7). The
group re-assigned to tretinoin treatment had a further overall
improvement of lightening of lesions. In contrast there was no
further improvement in patients who received vehicle during
the six month follow-up. However, lightening and resolution of
lesions seen during the first ten months of treatment were not
visibly reversed during this period of
discontinuation.
The efficacy of topical
tretinoin has been assessed in the treatment of photo-ageing
in racial groups other than Caucasians.6,7,8 In these trials,
topical tretinoin has been shown to significantly lighten
post-inflammatory hyperpigmented lesions (p < 0.001)6 and
melasma7 in black patients and to significantly lighten the
hyperpigmentation of photo-aging in Chinese and Japanese
patients (p < 0.05).8
Adverse
Effects
In clinical trials with topical
tretinoin, the only adverse reaction seen was cutaneous
irritation. Mild to moderate skin reactions (eg dryness,
peeling, erythema, burning, stinging, pruritis) were seen in
up to 92% of patients treated with tretinoin, with higher
incidence being seen with higher concentrations.3 Adverse
effects were responsible for about 3% of patients being
withdrawn from the studies.1,2,3
Topical tretinoin should not be
used during pregnancy as there have been reports of congenital
defects associated with maternal use.9
Summary
There is evidence from controlled
clinical trials in large numbers of patients that tretinoin
0.05% cream can improve some of the clinical signs of
photo-aging. The only adverse drug effects associated with
this treatment are cutaneous irritation and dermatitis.
However, the use of measures to prevent photodamage should not
be undermined and avoidance of sun exposure and use of high
protection sunblock are undoubtedly still the most rational
approaches to preventing photodamage.
Medicine Classification
Prescription Medicine.
Package Quantity
20g per tube.
Further Information
RETINOVA also contains: Paraffin
light liquid, Sorbital Solution, Edetate Disodium,
Methylparahydroxybenzoate, Dimethicone, Quaternium-15,
Hydroxyoctacosanyl Hydroxystearate, Methoxy PEG-22/Dodecyl
Glycol Copolymer, PEG-45/Dodecyl Glycol Copolymer,
Stearoxytrimethylsaline and Stearyl Alcohol, Citric Acid
Monohydrate, Butylated Hydroxytoluene, Fragrance and Purified
water.
Store below 25°C. Do not
freeze.
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