Safety of Topical Minoxidil Solution: A One-Year, Prospective, Observational Study

Efficacy and safety of a new 5% minoxidil formulation in male androgenetic alopecia: A randomized, placebo-controlled, double-blind, noninferiority study

BACKGROUND

Androgenetic alopecia (AGA) is the most common cause of hair loss in men. Topical minoxidil solutions can help to treat AGA but have to be applied continuously to be effective.

OBJECTIVES

A new minoxidil formulation with improved cosmetic characteristics (DC0120, Pierre-Fabre Dermatologie) was tested for noninferiority vs a comparator minoxidil product (ALOSTIL^® , Johnson & Johnson) in stimulating hair growth in men with AGA.

METHODS

Two 10 cm² areas on the scalp of each subject were randomized to receive DC0120, the comparator, or one of their corresponding vehicles, applied twice per day for 16 weeks. Nonvellus target area hair count (TAHC) was measured within treatment areas at baseline (day 1) and after 8 and 16 weeks by digital phototrichogram.

RESULTS

Two hundred and twenty subjects were included and randomized, of which 210 completed the study. The mean change in nonvellus TAHC between baseline and week 16 was +22.0 hairs/cm² (95% CI: 18.1; 25.9) in the DC0120 group and +20.5 hairs/cm² (95% CI: 16.6; 24.4) in the comparator group. The adjusted mean difference in TAHC changes between the two treatments was +1.5 hairs/cm² (95% CI -2.3; 5.2), with the lower 95% confidence interval above the noninferiority threshold of -7 hairs/cm² . This indicated that DC0120 was noninferior to the comparator. Both minoxidil treatments also increased nonvellus TAHC compared to vehicle groups at 8 and 16 weeks. No new safety signals were observed.

CONCLUSIONS

DC0120 was as safe and effective as a similar marketed minoxidil product for stimulating hair growth in men with AGA.

Establishment of an evaluation method to detect drug distribution in hair follicles

Development of an appropriate method to evaluate drug disposition or targeting ability in hair follicles (HFs) is urgently needed in order to develop useful pharmaceutical products with pharmacological effects in HFs. In the present study, a cyanoacrylate biopsy (CB) method was used to measure drug disposition in HFs using a model hydrophilic drug, caffeine (CAF), and a lipophilic drug, 4-butylresorcinol (BR), in excised porcine skin. As a result, the height of HF replicas and the recovery ratio decreased with an increase in the application times of the CB method. HF replicas with a length of approximately 175 µm were obtained using a single application of the CB method. Drug distribution in the HF was detected even 5 min after topical application regardless of the lipophilicity of the drugs, although no drug disposition was observed in the deeper layers of the stratum corneum at the same time (5 min). Furthermore, significantly higher amounts of BR were observed in the stratum corneum and HF, compared with those of CAF. These results suggested that the CB method could be useful to evaluate the safety and efficacy as well as the disposition of topically applied chemicals, especially for HF-targeting drugs.

Iontophoresis-targeted, follicular delivery of minoxidil sulfate for the treatment of alopecia

Although minoxidil (MX) is a drug known to stimulate hair growth, the treatment of androgenic alopecia could be improved by delivery strategies that would favor drug accumulation into the hair follicles. This work investigated in vitro the potential of iontophoresis to achieve this objective using MX sulfate (MXS), a more water-soluble derivative of MX. Passive delivery of MXS was first determined from an ethanol-water solution and from a thermosensitive gel. The latter formulation resulted in greater accumulation of MXS in the stratum corneum (skin's outermost layer) and hair follicles and an overall decrease in absorption through the skin. Anodal iontophoresis of MXS from the same gel formulation was then investigated at pH 3.5 and pH 5.5. Compared with passive delivery, iontophoresis increased the amount of drug reaching the follicular infundibula from 120 to 600 ng per follicle. In addition, drug recovery from follicular casts was threefold higher following iontophoresis at pH 5.5 compared with that at pH 3.5. Preliminary in vivo experiments in rats confirmed that iontophoretic delivery of MXS facilitated drug accumulation in hair follicles. Overall, therefore, iontophoresis successfully and significantly enhanced follicular delivery of MX suggesting a useful opportunity for the improved treatment of alopecia.

Androgenetic alopecia in the paediatric population: a retrospective review of 57 patients

BACKGROUND

Hair loss is an unwelcome event at any age, but it can be particularly distressing for adolescents and their families. While androgenetic alopecia (AGA) is the most common form of hair loss in adults, little is known about its prevalence, clinical features and response to treatments in the paediatric population.

OBJECTIVES

To better characterize the causes of alopecia in a paediatric population.

METHODS

We performed a retrospective chart review to identify all patients with hair loss seen in an academic paediatric dermatology practice at New York University over a 12-year period to better characterize the causes of alopecia in this population. We review the clinical and histological features, natural progression and associated laboratory abnormalities of AGA in 57 paediatric patients.

RESULTS

AGA was identified as the most frequent cause of hair loss in adolescents and the second most common diagnosis overall. The male to female ratio was 2 : 1 and the average age at initial presentation with AGA was 14.8 years. Adolescent girls had diffuse thinning or thinning at the crown, and boys frequently presented with female pattern hair loss. When biopsies were performed, perifollicular inflammation was a common finding. A family history of AGA was reported in 83% of patients. Laboratory evaluation for androgens revealed polycystic ovarian syndrome in three girls and late-onset congenital adrenal hyperplasia in one boy.

CONCLUSIONS

AGA is the most common form of hair loss in adolescents, and can be the presenting sign of an underlying endocrine disorder. An accurate and timely diagnosis is essential for appropriate medical and psychosocial intervention when warranted.

Medical treatments for male and female pattern hair loss

Male and female pattern hair loss affects a large percentage of the population, and patients frequently present for treatment of this to their dermatologist. Here we review the many treatments available for hair loss. We review the evidence for each, and outline the most effective treatment strategies for both men and women.

LEARNING OBJECTIVE

At the conclusion of this article, the reader should be able to describe the most effective treatments for hair loss, understand their mechanism(s) of action, and explain which treatments are the best in different settings.

Management of hair loss

The management of patients with hair loss requires a customized plan. Diagnosis, prognosis, psychosocial impact, treatment options, and patient preference are key determinants. This article discusses current agents for the treatment of three commonly encountered nonscarring alopecias: male- and female-pattern hair loss, telogen effluvium, and alopecia areata. Algorithmic approaches to management are provided.