Clinical Use of Extracellular Vesicles in the Management of Male and Female Pattern Hair Loss: A Preliminary Retrospective Institutional Review Board Safety and Efficacy Study.

Background: Pattern hair loss is a common disorder in female and male patients. Objectives: To assess the safety, efficacy, and satisfaction of a single extracellular vesicle (EV) treatment over 6 months. Methods: A retrospective open-label study among 22 female and 9 male patients who demonstrated early stages of alopecia or were in remission from previous medical and surgical treatments. The amount of undiluted or diluted volumes of EV solution used was determined by the extent and degree of alopecia. Global photography, Patient Global Aesthetic Improvement Scale (PGAIS) and Investigator Global Aesthetic Improvement Scale (IGAIS) questionnaires, and trichoscan measurements were compared at baseline and 6 months in 3 response categories. Results: Frequent growth responses were observed: older aged females and younger aged males, shorter history of alopecia, earlier stages of hair loss, larger and undiluted volumes of XoFlo, previous positive responses to medical and surgical treatments, and absence or control of disease factors affecting the hair. Global photography, trichoscan for density, follicle diameter, terminal: vellus ratio, and PGAIS/IGAIS satisfaction questionnaires at baseline and 6 months were useful in assessing clinical efficacy. No significant adverse reactions were observed. Conclusions: Intradermal injections with varying doses of EVs were safe and effective among indicated alopecic female and male patients. Findings suggest that the presence of positive factors, absence of conditions known to negatively affect hair growth, and administration of larger volumes of XoFlo may have a significant influence on the use of this new cell-free therapy. Level of Evidence 4: