Exosome Injection Versus Topical Minoxidil for Androgenetic Alopecia

A Prospective, Randomized, Comparative Study of the Efficacy and Safety of Intradermal Exosome Injections Versus Topical Minoxidil in Patients With Androgenetic Alopecia

Androgenetic alopecia (AGA) is a common form of hair loss characterized by progressive hair follicle miniaturization. This prospective randomized comparative study evaluates the efficacy and safety of intradermal exosome injections compared with 5% topical minoxidil in patients with AGA. Forty patients were randomly assigned to receive either intradermal exosome injections or topical minoxidil for three months, with clinical, trichoscopic, patient-reported, and safety outcomes assessed at baseline, after treatment, and at 3-month follow-up.

Androgenetic alopecia is the most common form of hair loss and is associated with progressive shortening of the anagen phase and miniaturization of hair follicles. Conventional treatments such as topical minoxidil have variable efficacy and require continued use to maintain results. Exosome-based therapy has emerged as a potential regenerative approach because exosomes can deliver bioactive molecules that may stimulate hair follicle activity and promote the anagen phase.

This prospective, randomized, comparative study included 40 patients with confirmed androgenetic alopecia recruited from the Dermatology and Venerology Department outpatient clinic at Tanta University Hospitals. Participants were randomly allocated using a computer-generated sequence into two equal groups of 20 patients each. Group A received intradermal injections of adipose-derived mesenchymal stem cell exosomes every four weeks for three months, while Group B applied 5% topical minoxidil twice daily for three months.

Treatment efficacy was evaluated using clinical assessment, standardized scalp photography, the Global Aesthetic Improvement Scale (GAIS), trichoscopic assessment of hair density and shaft diameter, and histopathological/immunohistochemical evaluation in biopsied patients. Patient satisfaction and adverse events were also recorded. Assessments were performed at baseline, immediately after the 3-month treatment period, and after a further 3-month follow-up period.

The study aims to provide comparative clinical evidence regarding the efficacy and safety of intradermal exosome therapy versus topical minoxidil for androgenetic alopecia. The protocol received approval from the Institutional Review Board of Tanta University (Approval Code: 36264MS541/3/24), and written informed consent was obtained from all participants.

Inclusion Criteria:

• Were male or female patients with a confirmed diagnosis of androgenetic alopecia (AGA).

Had not received any treatment for AGA for at least 6 months before study initiation.

Provided written informed consent. Agreed to attend the scheduled follow-up assessments and undergo photographic documentation.

Exclusion Criteria:

• Concurrent scalp diseases. A history of bleeding disorders. Current use of anticoagulant medications. Known keloidal tendency. History of psoriasis or lichen planus. Significant cardiac, hepatic, or renal disease. Any major systemic illness. Pregnancy or lactation.