16 December 2019

Biologic gets green light for children’s severe eczema

Clinical Dermatology Paediatrics

Children with moderate-to-severe atopic dermatitis can now be prescribed the interleukin-4 and interleukin-13 inhibitor dupilumab (Dupixent).

The drug was approved by the TGA for use in adults last year, and it’s indications have now expanded to include children as young as 12.

Dupilumab isn’t yet PBS listed for adults or children, and it is a pricey treatment, setting patients and parents back $1,615.38 per month. Sanofi Genzyme, the drug’s sponsor, is campaigning to get the treatment listed on the PBS.

The treatment is administered through subcutaneous injection – an initial dose of 600mg, followed by two 300mg injections per month.

Dupilumab is a human monoclonal antibody that selectively inhibits the key type 2 cytokines involved in atopic dermatitis, interleukin-4 and interleukin-13.

The drug is novel because it is the first biological therapy approved for moderate-to-severe atopic dermatitis.

“It blocks interleukins 4 and 13, which are strong drivers of atopic dermatitis,” said Dr Gayle Ross, a dermatologist and the lead clinician in atopic dermatitis at the Royal Melbourne Hospital.

“It is extremely effective, and considered much safer than traditional treatments, as it is targeted and does not suppress the immune system,” she said. “However, the main side effect to be aware of is conjunctivitis.”

A Phase 3 clinical trial involving around 250 adolescents with moderate to severe atopic dermatitis found the biologic improved symptoms and quality of life more than a placebo over 16 weeks.

In the trial, the adverse events were similar in the dupilumab group and the placebo group, except for conjunctivitis, which was higher in the dupilumab group (~10% vs 5% in the placebo group).

“I currently have nine patients on dupilumab, who were granted compassionate supply due to the severity of their condition over 12 months ago,” Dr Ross said.

“They are all doing extremely well, and feel this drug is life-changing. Unfortunately, Sanofi is not allowing any further compassionate access currently. While it is available on private script, I have not had any patients take this up yet due to the cost.”

Professor Rod Sinclair, a dermatologist at The University of Melbourne, said: “Dupilumab is the first major breakthrough for atopic dermatitis in 20 years and brings the treatment of eczema into the 21st century in line with other major skin disorders like psoriasis.”

Professor Sinclair was the principal investigator in both the phase 2 and phase 3 studies of the drug.

“I was able to see first-hand the transformational effect of this medication on people’s lives,” he said.

“Severe eczema is a dreadful condition and previous treatments like prednisolone and cyclosporin often had severe side effects. Sleep disturbance is a major factor not only for the affected children, but often the whole family. When the child wakes, often the parents to do. The severe associated itch affects school performance and all aspects of life.

“The medication is not listed on the PBS and therefore only available to people who can afford it (about $15,000 per year) or people enrolled in clinical trials who receive the medication for free,” he said.

Sanofi is also running a Phase 3 trial for dupilumab to treat severe atopic dermatitis in children aged 6 to 11.

In May, dupilumab was also approved by the TGA for the treatment of moderate to severe eosinophilic asthma in patients aged 12 and over, as well as maintenance therapy for oral corticosteroid dependent asthma.