EGPA
Just as there is excitement about these studies with respect to GPA and MPA, the use of interleukin (IL) 5 inhibitors in eosinophilic granulomatosis with polyangiitis (EGPA) sparks interest as well. Dr. Merkel stated that IL-5 inhibitors are the first class of drugs other than glucocorticoids with solid data from randomized controlled trials to show efficacy in the treatment of EGPA. These medications tend to be well tolerated, and the uptake in the U.S. has been high.
It is important to point out that data on efficacy are currently restricted to treatment of upper and lower respiratory airway disease. These treatments may be useful to treat other, more severe manifestations of disease, but additional studies are needed to prove this.
Emerging Illnesses
Dr. Merkel concluded his talk by pointing out two relatively new conditions in the field of rheumatology. The first is deficiency of adenosine deaminase 2 (DADA2), a monogenic disease with loss of function mutations in the CECR1 gene. The condition can present with early-onset strokes, and signs and symptoms that may mimic those of polyarteritis nodosa.
The other, even newer, condition is VEXAS syndrome, which stands for vacuoles, E1 enzyme, X-linked, autoinflammatory and somatic. This disease involves somatic mutations in the UBA1 gene, affects mostly men over the age of 60 and has consistent features that include elevated mean corpuscular volume (MCV) and high C-reactive protein (CRP). Given a recent study showed that as many as 1 in 14,000 patients in a healthcare system cohort harbored a UBA1 disease-causing variant and showed hematologic, autoimmune, pulmonary and dermatologic clinical manifestations seen in VEXAS syndrome, the condition may be more common than was previously known.5
In Sum
Dr. Merkel’s presentation was well received by an audience that understands all too well the significant morbidity and mortality that can occur in the setting of vasculitis. To best help our patients, we will rely on more groundbreaking research studies and evidence-based guidelines in the years ahead to serve as a North Star in our management of patients with vasculitis.
Jason Liebowitz, MD, is an assistant professor of medicine in the Division of Rheumatology at Columbia University Vagelos College of Physicians and Surgeons, New York.
References
- Guillevin L, Pagnoux C, Karras A, et al. Rituximab versus azathioprine for maintenance in ANCA-associated vasculitis. N Engl J Med. 2014 Nov 6;371(19):1771–1780.
- Smith RM, Jones RB, Specks U, et al. Rituximab versus azathioprine for maintenance of remission for patients with ANCA-associated vasculitis and relapsing disease: an international randomised controlled trial. Ann Rheum Dis. 2023 Jul;82(7):937–944.
- Walsh M, Merkel PA, Peh CA, et al. Plasma exchange and glucocorticoids in severe ANCA-associated vasculitis. N Engl J Med. 2020 Feb 13;382(7):622–631.
- Jayne DRW, Merkel PA, Schall TJ, et al. Avacopan for the treatment of ANCA-associated vasculitis. N Engl J Med. 2021 Feb 18;384(7):599–609.
- Beck DB, Bodian DL, Shah V, et al. Estimated prevalence and clinical manifestations of UBA1 variants associated with VEXAS syndrome in a clinical population. JAMA. 2023 Jan 24;329(4):318–324.
