Research & Evidence

A 24-week, multicentre, randomised, double-blind, double-dummy, parallel-group phase III non-inferiority trial of 0.25% topical finasteride spray solution versus oral finasteride 1 mg/day in men with mild-to-moderate androgenetic alopecia. The primary endpoint was change in target-area hair count.

Topical finasteride met non-inferiority compared with oral finasteride for the primary endpoint, with a smaller maximum reduction in serum DHT and a comparable safety profile relative to placebo over the treatment period. The trial is the principal phase III evidence cited in support of topical finasteride as a treatment option for male AGA.

A pharmacokinetic and pharmacodynamic evaluation of the 0.25% topical finasteride spray (development code P-3074, the formulation underlying subsequent Finjuve / topical finasteride products). The study examined plasma finasteride levels, scalp DHT suppression and serum DHT after multiple-dose topical application in healthy male volunteers.

Topical administration produced meaningful suppression of scalp DHT with substantially lower systemic finasteride exposure than oral 1 mg dosing — the central pharmacological rationale for a cutaneous route.

An open-label, single- and multiple-dose pharmacokinetic study describing absorption of 0.25% topical finasteride, time to steady state, and the corresponding effect on plasma testosterone and DHT in healthy male volunteers.

Useful as primary-source PK data for the topical formulation. Confirms that the topical route produces lower plasma finasteride concentrations and a smaller percentage reduction in serum DHT than the oral 1 mg dose.

The pivotal 12-month, randomised, double-blind, placebo-controlled multicentre trial that established oral finasteride 1 mg/day as effective for male androgenetic alopecia. Although the trial concerned the oral form, it is the foundational efficacy reference for all subsequent finasteride research, including topical formulations.

A systematic review of clinical trials of topical finasteride. The authors conclude that topical finasteride significantly improved hair count and density compared with placebo across the included studies, with a favourable adverse-event profile relative to oral therapy. Limitations include heterogeneity of formulations, concentrations and outcome measures across trials.

A narrative review of the topical finasteride literature in male AGA, summarising vehicle considerations, dosing and the comparative safety case versus oral finasteride. Useful as a clinician-friendly orientation to the topical evidence base.

Network meta-analysis comparing licensed and off-label therapies for AGA, including topical and oral finasteride and topical and oral minoxidil. Provides one of the more rigorous indirect comparisons of relative efficacy across the commonly used interventions.

Randomised comparative trial of oral finasteride alone, topical minoxidil alone, and the combination in men with AGA. Combination therapy produced greater improvement than either monotherapy, supporting the routine combination prescribed by hair-loss clinics in the UK and Ireland.

Twelve-month observational study reporting that topical minoxidil 5% solution stabilised or improved hair loss in the majority of treated men. Frequently cited alongside finasteride trials to anchor expectations of monotherapy efficacy.

A survey-based description of symptoms reported by men who attribute persistent effects to prior oral finasteride use. Cited in the wider regulatory debate around post-finasteride syndrome (PFS), and useful context when discussing the comparative safety case for topical delivery.

UK regulator's communication strengthening the warning about psychiatric and sexual side effects with finasteride, asking prescribers to advise patients on symptoms to watch for. Required reading for anyone prescribing or dispensing finasteride in the UK; the same considerations are reflected in patient information for topical formulations.

The European regulatory review that led to updated product information for finasteride products across the EU, including stronger labelling on potential psychiatric and sexual side effects and on persistence of symptoms after discontinuation in some users.

A concise reference for the androgen biology of pattern hair loss: the role of testosterone and DHT, the 5-alpha reductase isoforms, and the rationale for inhibiting type II 5-alpha reductase as a therapeutic target.

A broad, frequently cited overview of the genetics, hormonal biology and treatment landscape of androgenetic alopecia. Useful as a general background reference rather than as evidence for a specific therapy.

UK reference material on finasteride dosing, contraindications, interactions and monitoring, intended for prescribers and pharmacists. Note that as of publication of this page, BNF and NICE CKS coverage focuses on the oral 1 mg and 5 mg products; topical preparations are dispensed under their own product information.