Reversible azoospermia associated with the selective JAK1 inhibitor abrocitinib: a case report

To describe a case of reversible azoospermia temporally associated with abrocitinib treatment in a man with severe atopic dermatitis (AD) and discuss its potential implications for male reproductive safety.

Case report.

A 38-year-old normal-weight man with highly refractory AD, a history of neonatal orchidopexy, and primary infertility.

Clinical, hormonal, and semen evaluation before and after discontinuation of abrocitinib therapy (200mg/day).

Semen parameters and reproductive hormone profile.

Two consecutive semen analyses performed during abrocitinib treatment demonstrated azoospermia. Baseline endocrine evaluation showed elevated follicle-stimulating hormone (FSH; 12.3 mIU/mL), suggestive of seminiferous tubule dysfunction. Abrocitinib was discontinued, and reassessment after 3 months revealed complete recovery of spermatogenesis, with a sperm concentration of 50 million/mL. Although isolated teratozoospermia persisted, FSH levels normalized (8.6 mIU/mL) and inhibin B increased markedly (from 58 to 135 pg/mL), consistent with improved Sertoli cell function. The temporal association between drug withdrawal and recovery supports a potential reversible effect on spermatogenesis.

This is, to our knowledge, the first report describing reversible azoospermia temporally associated with abrocitinib therapy. Although causality cannot be established from a single observation, this case raises a potential safety signal regarding the effects of selective JAK1 inhibition on male reproductive function. Further preclinical studies, pharmacovigilance analyses, and prospective clinical investigations are warranted to determine whether prolonged or high-dose abrocitinib exposure may adversely affect spermatogenesis in susceptible individuals.