Platelet-rich plasma shows limited efficacy in hair growth restoration in alopecia areata

While platelet-rich plasma failed to yield improvements over placebo in alopecia areata as assessed by Severity of Alopecia Tool score, some parameters of immune response did improve with treatment, according to a study.

“Platelet-rich plasma has shown some promise in the treatment of alopecia areata,” Vishal Gupta, MD, of the department of dermatology and venereology at the All India Institute of Medical Sciences, New Delhi, and colleagues wrote.

The aim of the randomized, placebo-controlled, split-head study was to assess the impact of this treatment approach on hair regrowth and lesional T-cell cytokine expression in a cohort of 27 patients.

Eligibility criteria included Severity of Alopecia Tool (SALT) score of 25% or greater.

Treatment protocols called for three intradermal injections of either platelet-rich plasma or saline at monthly intervals on alopecia patches on either side of the scalp of the patients.

Final follow-up occurred at 3 months after the last session.

The researchers then compared lesional T-cell cytokine messenger RNA expression before and after treatment with the study intervention.

Results showed no significant change in mean SALT score in either the platelet-rich plasma or placebo-treated sites at any visit. However, the researchers noted that the mean percentage reduction in this score in the treatment arm was 9.05% ± 36.48% compared with 4.99% ± 33.88% in the placebo arm (P = .049) at the final evaluation.

A 50% reduction in SALT score occurred in 14.8% of patients in the treatment group and 7.4% of those in the placebo group.

Significant decreases were observed in the mean interferon gamma (P = .001) and IL-17 cytokine (P = .009) messenger RNA expression in the treatment arm, while significant increases were reported for the mean IL-10 (P = .049) and FOXP3 (P = .011) messenger RNA expression after platelet-rich plasma treatment, according to the findings.

Further results showed that 22.2% of the cohort had comparable hair regrowth on both sides of the scalp, regardless of treatment with plasma or placebo, while 33.3% showed improvement on the plasma-treated side and 11.1% showed improvement on the placebo-treated side.

No hair growth on either side was observed in 14.8% of the cohort, while 18.5% reported worsening of hair growth on both sides.

The researchers noted that the study was limited by a small sample size and short follow-up duration.

“Platelet-rich plasma was found to have limited efficacy in alopecia areata,” the researchers wrote. “However, it may play a role in restoring immune balance in the alopecic patches.”