Abstract
Approval of novel pharmacologic treatments are contingent on safety/efficacy/dosing data acquired from well-designed interventional studies. While clinical trials continue to push the frontiers of medicine, data obtained from nonrepresentative trials should not be regarded as highly generalizable evidence. 1 Alopecia areata and androgenetic alopecia are diseases of the hair follicle which often require pharmacologic interventions; therefore, clinical trials provide much needed data for safety/efficacy. The aim of this study was to evaluate the reporting and representation of sex/race/ethnicity in alopecia areata and androgenetic alopecia interventional studies.
ClinicalTrials.gov was searched using the terms “alopecia/alopecia areata/androgenic alopecia/androgenetic alopecia” in July 2021. Search criteria were defined as: interventional, with results, and completed. The following exclusion criteria were applied: incorrect condition, non-phase I/II/III, and conducted entirely outside of the United States. Trial records were inspected to acquire data on patient demographics and official trial publications were used to cross-reference ClinicalTrial.gov data. Alopecia areata trials included patients of both sexes. Androgenetic alopecia trials were either fully-female, fully-male, or both.
Data analysis was performed using SPSS Statistics (v25) with an alpha of 0.05. Distribution differences between two/three independent groups were assessed using the Mann-Whitney/Kruskal-Wallis tests. Participation-to-prevalence ratios (PPRs) were computed to determine whether or not females were adequately represented. 1,2 PPR was obtained by dividing the trial proportion of females by their population-level disease prevalence. Population-level epidemiology data were acquired from the Global Burden of Disease database. PPR of 1.0 ± .2 was interpreted as adequate female representation. 3 Values below/above this range suggested underrepresentation/overrepresentation. PPR analysis was only performed for alopecia areata trials (N = 12).
A total of 2207 patients (21 trials) were analyzed. Sex data were fully reported and female representation in alopecia areata trials was acceptable (64.8% female; PPR = .86, 95% CI [0.74, 0.98]). There was no significant PPR difference between randomization (P = .343), funding types (P = .283), or study location (P = .500). Compared to a previous study which found 87.5% of alopecia areata studies reported sex and 42.9% did not have ≥45% female representation, 4 our findings suggested a detectable improvement.
Minority representation in alopecia areata and androgenetic alopecia clinical trials were notably lacking. Overall, the proportions of Black, Asian, AI/AN, and Hispanic/Latino trial participants (Table 1) were lower than their respective stakes in the U.S. population. 5 Between alopecia areata and androgenetic alopecia, the latter enrolled significantly more NH/OPI (P = .012) patients, meanwhile the former had no representation from this race group. This analysis was based on limited studies which reported race/ethnicity data, therefore it would be incongruous to assume that demographic representation would be any better in studies which failed to report. With all things considered, alopecia clinical trials are far from achieving racial and ethnic equity.
Representation of Race and Ethnicity in Trials for Alopecia Areata (N = 12) and Androgenetic Alopecia (N = 9). Trials Which Did Not Report Such Data Were Omitted, and Percentages Were Adjusted to Reflect the Proportion Among Trials That Reported Data on the Demographic. Trial Populations With Missing Demographic Data Were Subtracted From the Corresponding Total Population.
Abbreviations: AI/AN, American Indian/Alaska Native; NA, not applicable; NH/OPI, Native Hawaiian/Other Pacific Islander; NR, not reported; US, United States.
Notes: “International” (Location) represents studies conducted in the US plus one or more other country. “US” and “Non-US” (Sponsor Type) indicate where the sponsor company’s headquarters is located. “Sex Enrollment” refer to inclusion criteria of androgenetic alopecia trials (e.g., “Female” =only enrolled female sex).
Our study unveiled key reporting and demographic characteristics of clinical trials for alopecia. Clinical trials must strive to enhance reporting transparency and engage in standardized reporting of subpopulation data such as race and ethnicity. Better recruitment, enrollment, and retention practices must be explored to combat inequitable trial representation, and if left untreated, massive public health ramifications will ensue.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
