Rheumatic Immune-related Adverse Effects with Checkpoint Inhibitor Therapy Save

A retrospective study of patients who developed rheumatic immune-related adverse events (R-irAEs) after receiving immune checkpoint inhibitors (ICIs) at two oncology centers in Spain suggests that early recognition can lead to effective management that allows continuation of cancer therapy. 

An observational found that among the 734 ICI treated patients, 227 (319%) developed any irAEs; 54 (7.35%) were R-irAEs, accounting for 248% of all irAEs. 

The most common cancers were lung cancer (44%) and melanoma (33%).  

Most R-irAEs occurred within six months of ICI initiation. Most were treated with anti-PD1 therapy (89%), with fewer taking anti-PD-L1 (9%) or anti-CTLA 4 (2%). 

The most frequent rheumatic irAE manifestations included polymyalgia rheumatica (n = 12), arthritis/arthralgia (n = 26) and fewer with myositis (5), Sjogrens (5) and psoriatic arthritis (3). Myositis is a particularly severe manifestation that presents at the first or second cycle of treatment. 

Corticosteroids were the primary treatment (n=40; 74%) for many with fewer requiring additional immunosuppressants (n=3), biologic agents (n=3), and intravenous immunoglobulins (n=4)

The five patients with ICI-myositis were treated most aggressively, with csDMARDs (mycophenolate), two with bDMARDs (Rituximab) and 4 with IVIG. Despite aggressive treatment, only one had clinical improvement. 

Awareness and standardized guidelines are needed to improve the diagnosis and care of these adverse events.