AFFINITY Study - Combination Biologic Therapy in Psoriatic Arthritis Save

A pilot trial assessed the efficacy and safety of the guselkumab+golimumab (COMBO) combination versus guselkumab (GUS) monotherapy in active PsA (failing a prior tumor necrosis factor inhibitor (TNFi-IR) and showed superiority in ACR 50 responses but not minimal disease activity (MDA; the primary endpoint). PsA patients with an elevated CRP benefitted most from COMBO treatment.

A total of 91 patients with active -IR PsA (≥3 tender/swollen joints) were randomized (2:1) to COMBO vs GUS every-4-weeks (Q4W) for 20 weeks. The primary endpoint was Wk 24 minimal disease activity (MDA) achievement. 

At baseline, participants had a median of 13/8 tender/swollen joints and psoriatic body surface area of 3%; 23% had dactylitis. 

At Wk 24 MDA was achieved in: 29% COMBO vs 22% GUS monotherapy, (OR 1.4 [0.6, 3.3]; P=0.557). But the ACR50 responses favored the COMBO (44%) over GUS (22%) (nominal P=0.034). 

MDA response was greater in those with an elevated CRP ≥0.3mg/dL (OR: 12.3; P=0.025.

ACR50 repsonses were also better (32% vs. 5%; P=0.003) with and elevated CRP. 

Other secondary outcomes were greater w/ COMBO therapy - ACR20 (66% vs. 44%)/ACR70 (27% vs. 16%) responses and physical function improvements.Yet, COMBO therapy was not better at psoriasis, dactylitis, or enthesitis outcomes. No new safety signals were seen, including no tuberculosis or opportunistic infections.

MDA, the primary endpoint was not achieved, but many would agree that is a high bar for any novel therapy in PsA (requires TJC <1, SJC <1, and PASI <1).  Nonetheless, all secondary endpoints favored the efficacy and safety of COMBO therapy over GUS monotherapy in TNFi-IR PsA patiens. Further studies are warranted.