Janssen, a subsidiary of Johnson and Johnson (J&J), recently announced that Tremfya (guselkumab) received Food and Drug Administration (FDA) approval for patients with active psoriatic arthritis (PsA). Despite being launched in a fairly mature market, if J&J is able to contract aggressively with pharmacy benefit managers, leading data and analytics company GlobalData expects that Tremfya will still be able to stake a claim in the market. By 2028, Tremfya is expected to net $361m in the US and $577m globally for the indication of PsA.

Tremfya is the first selective IL-23 inhibitor available for the disease and the second IL-23 inhibitor overall, following Janssen’s own Stelara (ustekinumab). Tremfya beat out competing IL-23s: AbbVie’s Skyrizi (risankizumab) and SunPharma’s Ilumya/Ilumetri. The selective IL-23 inhibitors represent the most promising pipeline drug class for PsA. 

Tiffany Chan, Immunology Analyst at GlobalData, explains: “Tremfya is expected to do well, based on J&J’s previous experience in the disease space marketing Stelara. Since Stelara’s patent is set to expire in 2023 in the US and Japan and in 2024 in the *5EU, it is likely that J&J will be able to preserve its position in the PsA space with Tremfya’s launch.”

Tremfya and the other selective IL-23 inhibitors is likely to also compete with the IL-17 inhibitors, Eli Lilly’s Taltz (ixekizumab) and Novartis’ Cosentyx (secukinumab), as second-line biologics for PsA patients. In head-to-head trials in plaque psoriasis, Tremfya was proven to be superior to Cosentyx but inferior to Taltz in skin clearance, from the IXORA-R and ECLIPSE trials, respectively. Tremfya appears to have a comparable safety profile to the IL-17 inhibitors but a better safety profile compared to Stelara, an IL-12 and IL-23 dual inhibitor. Notably, unlike their IL-17 counterparts, the IL-23 inhibitors are not contraindicated in patients with inflammatory bowel disease, which is a significant co-morbidity for PsA patients. Taken as a whole, Tremfya will pose a formidable challenge to the current marketed therapies. 

Chan adds: “Several key American patents are set to expire in the next five years, notably Stelara, but also the TNF-inhibitors AbbVie’s Humira and Amgen/Pfizer’s Enbrel, which have been the first line agents for many years. In the head-to head VOYAGE-2 trial in plaque psoriasis, Tremfya was superior to Humira, measured by the PASI90 criteria. If similar results were published in head-to-head PsA trials, Tremfya might be able to take patient shares that would have otherwise gone to cheaper anti-TNF biosimilars.”

*5EU: France, Germany, Italy, Spain and UK