Sales in major markets of drugs to treat psoriasis are set for robust growth over the next decade, increasing from $6.6 billion in 2013 to $10.7 billion in 2023, according to new forecasts.

Continued uptake of Janssen’s interleukin (IL)-12/23 inhibitor Stelara (ustekinumab) in earlier lines of therapy and the entry of treatments with novel mechanisms of action, notably the IL-17 inhibitors, will drive sales growth in the US, France, Germany, Italy, Spain, the UK and Japan, says the report, from Decision Resources.

Stelara is expected to achieve sales in these markets of some $2.4 billion in 2023, representing nearly 22% of total sales of psoriasis drug treatments, it adds.

Sales will also be driven by the launches and uptake of several emerging IL-17 inhibitors – Novartis’ secukinumab, Eli Lilly’s ixekizumab and Amgen/AstraZeneca/Kyowa Hakko Kirin’s brodalumab – plus Pfizer’s Jak inhibitor Xeljanz (tofacitinib).

Stelara and the TNF-alpha inhibitors will experience competition from emerging biologics and oral agents with novel mechanisms of action. Although concerns about their long-term safety profiles will restrict uptake initially, the emerging IL-17 inhibitors, Xeljanz, and emerging IL-23 inhibitors – Sun Pharma/Merck’s tildrakizumab and Janssen’s guselkumab – will increase competition within the TNF-alpha-refractory space, the report adds.

Oral therapies will expand treatment options, it goes on. Although the perceived lower efficacy of Xeljanz and concerns about the drug’s safety profile will restrict its market potential, Xeljanz will also compete for use in the TNF-alpha-refractory space. 

Another oral agent, Celgene’s phosphodiesterase-4 inhibitor Otezla (apremilast), has recently been approved for the treatment of psoriasis in addition to psoriatic arthritis, and will present an alternative to conventional systemic therapies as an interim step prior to biological therapy, it says.

“Thought leaders are particularly interested in the emerging IL-17 inhibitors, which have shown impressive efficacy in late-stage trials, with similar efficacy to the most potent current therapy for psoriasis, Janssen/Merck/Mitsubishi Tanabe Pharma’s Remicade (infliximab),” says Decision Resources group senior business insights analyst Kathryn Beane.

‘The efficacy and safety of emerging IL-17 inhibitors and IL-23 inhibitors are being evaluated in head-to-head clinical trials with current biologics, which will increase dermatologists’ confidence adopting these new therapies,” she adds.

These agents will initially compete in the TNF-alpha-refractory population and in patients who lose response to Stelara; however, “as their long-term safety profiles become more established, physicians will be comfortable prescribing them earlier - potentially as first-line biologics - in the treatment algorithm,” says Ms Beane.