Background and Importance Nonbullous congenital ichthyosiform erythroderma (NBCIE) is a rare disease that predominantly affects the skin, courses with palmoplantar keratoderma anhidrosis, and nail dystrophy. In severe cases, there is alopecia in certain areas.

Aim and Objectives The objective of this report is to describe the off-label use of ustekinumab in a patient with NBCIE, and to assess the safety of the treatment and tolerability profile.

Material and Methods We ran a descriptive study of 6 year old man with NBCIE diagnosed at the time of birth. The patient presented very itchy generalised NBCIE affecting patient’s quality of life. Patient’s skin was entirely affected with visible redness of approx 90% of body surface. Patient went through several treatments with no success: emollients emulsions, topical and oral corticosteroids and H1-antihistamines.

In February 2021, a new outbreak occurred that led the Dermatology department to request the off-label use of Ustekinumab.

The Pharmacy and Therapeutics Committee approved the treatment initiation based on the published efficacy studies. NBCIE patients have a dominant profile of TH17/IL-23 and it has previously been demonstrated the successful use of ustekinumab in patients affected by ichthyosis.

Efficacy was evaluated based on IASI scheme (Ichthyosis Area Severity Index).

Results The patient started treatment with ustekinumab in May 2021 with a dose of 1.2 mg/kg. Dosing was provided by the Hospital Pharmacy Department adjusted as per patient’s weight. The first 2 months, the patient received monthly doses while hereafter the dosing was adjusted to a bi-monthly frequency.

At the 3^rd month of treatment, the patient observed a mild improvement while presenting diffused erythema with scaling and rough skin in the folds, with an impact of 60% of body surface. At month 6, a fourth dose of 27,6 mg of ustekinumab weight-adjusted was provided. Thereafter, the patient observed a significant improvement that directly affected his quality of life, achieving a 60% reduction extension according to IASI and a 66% reduction erythema according to IASI and no side effects were reported.

Nevertheless Dermatology department request the off-label use of dupilumab.

Conclusion and Relevance Results demonstrate ustekinumab provides only partial response at month 6 of NBCIE treatment, with modest but significant improvement in the patient’s quality of life with a good safety profile.

Conflict of Interest No conflict of interest