Data from two Phase III trials show that brodalumab provides a significant improvement in disease control among patients with psoriatic arthritis who had an inadequate response to conventional therapy.
The term psoriatic arthritis (PsA), refers to a chronic inflammatory disorder that affects the joints, tendon sheaths, entheses and axial skeleton which can lead to severe joint damage and functional impairment. Conventionally, patients receive a range of therapies including non-steroidal anti-inflammatories, corticosteroids and synthetic disease-modifying anti-rheumatic drugs. When these treatments are unable to provide sufficient relief of symptoms, the next step involves the use of a biologic drug.
In an analysis of two randomised, double-blind placebo-controlled trials that included patients with an inadequate response to conventional treatment, a team from the Swedish Medical Research Centre, Washington, US, has examined whether brodalumab, which is not currently licensed for PsA, was an effective alternative treatment. All patients had at least 3 tender and swollen joints as well as active psoriatic skin lesions. In both of the trials, patients were randomised 1:1:1 to subcutaneous brodalumab 140 mg, 210 mg or placebo on day 1 and in the first two weeks and then once every two weeks through to the study end (week 24). The primary endpoint for both trials was ACR20 response, i.e., a 20% improvement in both tender and swollen joint count, assessed at week 16. Secondary endpoints, also measured at week 16, included a PASI75, i.e., 75% reduction in PASI score (which assesses disease severity) and a ACR50.
The combined population of the trials was 962 patients with a mean age of 49 years and an equal proportion of each sex. The pooled analysis from the two trials at week 16 showed that the ACR20 response rate was 45.8%, 47.9% and 20.9% for brodalumab 140mg, 210mg and placebo respectively (p<0.0001 in both cases vs placebo) and that this was maintained at week 24 (51% vs 53.6% vs 23.8%). The highest ACR50 response was achieved was early as week 2 for brodalumab 210mg and a PASI75 was achieved by 52.4%, 75.5% and 10.4% of participants given brodalumab 140mg, 210mg and placebo respectively.
Neither of the studies generated any new safety signals and the authors concluded that brodalumab represented an effective additional treatment for patients with PsA for whom conventional therapy was ineffective.
Citation Mease PJ et al. Brodalumab in psoriatic arthritis: results from the randomised phase III AMIVISION-1 and AMIVISION-2 trials. Rheum Dis 2020 doi:10.1136/ annrheumdis-2019-216835