The psoriatic arthritis (PsA) market was valued at $4.7bn in 2018 across the seven major markets (7MM*), and it is expected to grow to $9.3bn by 2028 at a compound annual growth rate (CAGR) of 7.0% according to GlobalData, a leading data and analytics company.

According to the company’s latest report, ‘Psoriatic Arthritis: Global Drug Forecast and Market Analysis to 2028’, growth will mainly be driven by the launch  of five new pipeline agents (which include injectable anti-interleukins and oral Janus Kinase [JAK] inhibitors) as well as increasing prevalence, diagnostic, and treatment rates.

SunPharma’s Ilumya/Ilumetri (tildrakizumab) and UCB’s bimekizumab join a large roster of injectable anti-interleukins, which includes such members as J&J’s Stelara (ustekinumab), Novartis’ Cosentyx (secukinumab), and Eli Lilly’s Taltz (ixekizumab). This growing class is set to challenge the branded TNF-inhibitors, the current standard of care. Combined with existing therapies, anti-interleukins are expected to earn $4.1bn in 2028 and capture 60.9% of global PsA sales.

Oral JAK inhibitors also represent a rapidly growing drug treatment class; AbbVie’s Rinvoq (upadacitinib), Gilead/Galapagos’ filgotinib, and Pfizer’s brepocitinib tosylate will join Pfizer’s Xeljanz (tofacitinib), the only JAK inhibitor currently available for PsA. The JAK inhibitor class is expected to grow to $261.0m by 2028.

Tiffany Chan, Immunology Analyst at GlobalData, explains: “Physicians are optimistic about the safety and efficacy profiles of the late-stage pipeline therapies. However, between the amount of experience physicians have with TNF inhibitors and the impact of biosimilar erosion throughout the forecast period, it is unlikely that this class will be unseated as the first-line biologic choice.

“A major barrier for growth in the psoriatic arthritis market will be the emerging use of biosimilars and generics for some of the key marketed products, namely AbbVie’s Humira (adalimumab) and Xeljanz. Due to price differentials, biosimilars and generics are expected to take a portion of their branded counterparts’ market share and to temper the growth of the PsA market overall.

“As PsA is a chronic condition, treatment costs are a significant factor in patient access to care. The annual costs of therapy (ACOTs) for the vast majority of agents used in PsA are expensive and continue to rise each year. The high cost is a major burden for both patients and insurance providers alike. The market entry of biosimilars and the launch of additional pipeline agents are expected to partially fulfil this unmet need, drive competition within the PsA market, and thus improve patient access.”

*7MM = US, France, Germany, Italy, Spain, UK and Japan.