Delgocitinib

JAK inhibitors (there are four different types: JAK1, JAK2, JAK3 and TYK2) are named after the messaging pathways they block within cells. In eczema, there is excessive inflammation in the skin, which causes redness — or darkening in skin of colour — and soreness or pain.

Multiple small cellular signals, called cytokines, drive that inflammation. Cytokines attach to receptors on cells, like a key fitting into a lock. Once attached, they trigger the production of even more cytokines, resulting in worsening eczema symptoms. Delgocitinib targets all four JAK pathways and works by blocking the specific messaging pathways causing the eczema inflammation.

Clinical research studies for delgocitinib involved 1,200 adults with moderate to severe chronic hand eczema who had not seen an improvement in their symptoms when using topical steroids for the previous 16 weeks. In the studies, 40–45% of patients using delgocitinib saw their hands become clear or nearly clear of CHE, compared with 15–20% of those using the placebo only. CHE improved with less itching, skin cracking and pain, and delgocitinib was well tolerated with patients experiencing only mild side effects.

Other clinical trials compared delgocitinib with alitretinoin (tablets) for adults with severe CHE over 24 weeks. The results showed delgocitinib worked as well as, and in some cases better than, alitretinoin — and with fewer side effects. A long-term extension study found CHE and skin improvements were maintained after a year, with no new side effects or safety concerns identified.

The research studies for delgocitinib do not assess its use alongside other topical drug treatments (for example, topical steroids, topical calcineurin inhibitors or topical antibiotics). Using other topical drug treatments in the same area at the same time as delgocitinib is not recommended. You are usually advised to continue using emollients, although you should leave a two-hour gap between applying delgocitinib and your emollient.

There is limited clinical research on the use of delgocitinib in pregnancy, so as a precaution avoid using it if you are considering pregnancy or are pregnant. Delgocitinib can be used when breastfeeding, as it is highly unlikely to pass through breast milk — however, ensure no cream is applied to the nipple area from the hands or wrists. There is no known effect on fertility.

The most common side effects include itching, 'pins and needles', redness and pain in areas where delgocitinib is applied. Only a small number of patients in the research trials experienced these reactions, all within the first week of treatment, and side effects for most people stopped during the first few days. Let your doctor or nurse know if you experience any side effects.

Some patients who use topical JAK inhibitor treatments have reported developing basal skin lesions (non-melanoma skin cancer) on their hands and wrists, particularly if they have additional risk factors for skin cancer. Occasionally, some people may develop a contact allergy to some of the preservatives in the cream (for example, benzyl alcohol and cetostearyl alcohol). Any allergic reactions or continued skin irritation should be discussed with your dermatologist.

Delgocitinib cream contains paraffin and is not flammable when in the tube or on the skin. However, clothing, dressings and bedding containing dried delgocitinib residue can catch fire more easily and burn more quickly. Take extra care and avoid naked flames or other potentially flammable heat sources when using the treatment. Wash gloves and affected clothing frequently to avoid residue build-up and reduce risk.