A PBS review has found that prescribing of dupilumab for atopic dermatitis has been higher than predicted since its listing in 2021, and some patients should be encouraged to discontinue the drug.

The analysis of PBS prescriptions (link here) conducted by the drug utilisation sub-committee (DUSC) of the Pharmaceutical Benefits Advisory Committee (PBAC) found that the number of dupilumab  treated patients and supplied prescriptions had increased every quarter since listing, and the rate of growth did not appear to be decreasing.

While the number of treated patients was within the estimate of eligible patients, it was not clear whether the higher use was due to use outside the restriction in patients with mild to moderate disease, the analysis noted.

The DUSC report found that uptake of dupilumab was not deterred by the inconvenience of subcutaneous injection compared to topical therapies. Also, the uptake of an oral therapy, upadacitinib, had been relatively low since its listing in 2022, perhaps due to a black box warning on upadacitinib.

Initiation of dupilumab was greatest in younger age groups  (20 to 24 year olds) and since most patients stayed on therapy, overall usage was likely to remain high, the report authors said.

Key findings from the report showed that:

• A total of 222,778 prescriptions of dupilumab for atopic dermatitis have been supplied to 16,995 patients since listing in 2021. In 2022, 104,967 prescriptions were supplied to 12,523 patients.
• Prescriptions supplied for the treatment of the whole body accounted for 82% of the 104,967 supplied prescriptions in 2022.
• Dermatology specialist prescribers accounted for 79% of the supplied prescriptions, and Immunology and Allergy specialist prescribers accounted for 8% of the supplied prescriptions.
• Of the 16,995 patients supplied dupilumab under a PBS item code for atopic dermatitis, 92% were previously supplied topical therapy through the PBS.

The report also noted that the proportion of use of dupilumab to treat patients with severe face and/or hand atopic dermatitis appeared to be increasing and accounted for 18% of prescriptions in 2023.

In its discussion of the findings, the DUSC commented that topical treatments for atopic dermatitis could be time consuming to apply for patients with severe disease and the injection appeared to be well tolerated by patients.

It also noted that dermatitis could be a seasonal disease, and patients may use varying amounts of topical treatment through a year.

“However, patients may choose to stay on dupilumab rather than being treated seasonally. DUSC commented that patients do not rebound when dupilumab is stopped, but considered it may have taken time for patients to access a specialist prescriber and they may be concerned about getting back into a specialist if treatment is ceased,” the authors wrote.

The Committee concluded that: “given the young age of initiating patients and the potential for treatment to become lifelong, there may need to be consideration given to discontinuing patients from dupilumab during periods of less severe disease, without restricting future access.”