As the lone IL-23 inhibitor approved for psoriatic arthritis, Johnson & Johnson’s Tremfya has established a niche with enticing potential among a field of formidable rivals.
Now comes evidence that could give Tremfya a boost among the competition.
A post-hoc analysis of data from two phase 3 trials shows that the drug is effective in treating patients with axial involvement, or a subset of psoriatic arthritis patients who have inflammation of the sacroiliac joints or spine, or both.
The condition occurs in more than 40% of those with psoriatic arthritis. It can appear in the earliest manifestations of the disease or long after its onset.
“The fact that we are bringing out new evidence for its efficacy, particularly for these patients with this axial manifestations, really underscores the unique benefits that Tremfya provides for PsA patients,” Andrew Greenspan, M.D., VP, Medical Affairs, Immunology at Janssen, said in an interview.
Investigators released the findings on Tuesday in The Lancet Rheumatology medical journal.
Tremfya, which scored its original FDA approval for plaque psoriasis in 2017, earned its nod for psoriatic arthritis last July based largely on the efficacy and safety results from the Discover phase 3 trials. Of the studies’ 1,120 participants, investigators identified 312 as having axial involvement.
For the work, researchers randomized those patients into three groups—118 in the placebo group, 103 in the dosed-every-four-weeks group and 91 in the dosed-every-eight-weeks group. After 24 weeks, the analysis of pooled data showed that the Tremfya patients had greater improvements than the placebo group in two key indices used to assess axial disease.
Further, those in the placebo group who transitioned at week 24 to Tremfya treatment every four weeks also showed improvement at week 52. The relatively small number of patients in the crossover group made it difficult to reach a definitive conclusion, researchers cautioned.
For those dosed with Tremfya, improvements began to show up at week eight and continued through week 52.
There was no significant difference in the response between those dosed every four and every eight weeks. The current allowed dosage for Tremfya is every eight weeks.
The post-hoc nature of the analysis, the team warns, limits the significance of the findings. A randomized, controlled trial is required to test the hypothesis more fully. To that end, Janssen is embarking on a study of 400 patients with psoriatic arthritis and imaged-confirmed axial involvement, Greenspan said. Through the six-month study, patients will undergo MRI exams to determine levels of inflammation.
With the potential to show a significant portion of psoriatic arthritis patients that Tremfya is their best option, the drug has a chance to attract a larger share of the market. It achieved blockbuster status in 2019 and registered $1.3 billion in sales last year in pursuit of PsA rivals Novartis’ Cosentyx, which earned $4 billion last year, and Eli Lilly’s Taltz, which had $1.8 billion in sales.
“What’s really notable about Tremfya, both in psoriasis and psoriatic arthritis, is that we do see very strong persistence of the effect of the drug,” Greenspan said. “That’s what’s exciting. Not only do patients improve with the drug, but they maintain that improvement.”