Abstract
<title>Abstract</title> <p>Background Androgenetic alopecia (AGA) affects up to 80% of men by age 80 and significantly impacts quality of life. Whilst finasteride and topical minoxidil remain first-line treatments, dutasteride offers more potent 5-alpha-reductase inhibition, and oral minoxidil provides systemic delivery that may enhance efficacy. Data on this combination in routine clinical practice remain limited. Objectives To evaluate the efficacy and safety of oral dutasteride 0.5 mg combined with oral minoxidil 2.5 mg and biotin 10 mg for male AGA in a large retrospective cohort. Methods We conducted a retrospective analysis of 621 male patients treated in the UK between January 2025 and December 2025. Treatment response was assessed using a validated 7-point Global Photographic Assessment (GPA) scale, scored independently by two blinded assessors. Primary outcomes included responder rates (GPA > 0) and least-squares mean (LS mean) score changes analysed using mixed-effects models for repeated measures (MMRM) with unstructured covariance and Kenward–Roger degrees of freedom. Secondary outcomes included predictors of response via Cox proportional hazards regression and adverse event rates from patient questionnaires and clinician consultations within 12 months. Results At 6 months, 61.5% of patients showed improvement (GPA > 0) and 98.5% remained stable or improved (GPA ≥ 0). MMRM analysis demonstrated progressive improvement, with LS mean scores of 0.44 (95% CI: 0.41–0.48) at months 1–2, increasing to 0.90 (95% CI: 0.80–1.01) at months 7+ (all p < 0.001 vs months 1–2). Effect sizes were large across all timepoints (Cohen's d = 0.87–1.78). Patients with severe baseline AGA showed significantly greater improvement than those with mild disease (LS mean difference 0.17, p = 0.017), and Cox regression confirmed that severe baseline severity predicted faster time to improvement (HR = 2.27, 95% CI: 1.39–3.72, p = 0.001). Adverse effects were uncommon: 2.9% of patients reported any adverse effect on systematic questionnaires, with treatment-related shedding (4.5%), low mood (1.0%), and decreased libido (1.0%) the most frequently reported. No serious adverse events occurred. Conclusions Oral dutasteride 0.5 mg combined with oral minoxidil 2.5 mg demonstrates high efficacy for male AGA, with over 60% improvement and 98% stabilisation at 6 months. The combination is well tolerated, with low adverse event rates. Patients with more severe baseline disease paradoxically show greater and faster treatment response, suggesting this combination may be particularly beneficial for advanced AGA.</p>