Around 5% of patients treated with dupilumab (Dupixent) for moderate-to-severe atopic dermatitis experience musculoskeletal (MSK) symptoms, according to the results of a descriptive study.
The main MSK symptom seen in the observational cohort was enthesitis, but some patients also experienced arthritis and tenosynovitis a median of 17 weeks after starting dupilumab treatment. Together these symptoms represent a new MSK syndrome, say researchers from the United Kingdom.
“The pattern of MSK symptoms and signs is characteristic of psoriatic arthritis/peripheral spondyloarthritis,” Bruce Kirkham, MD, and collaborators report in Arthritis & Rheumatology.
“We started a few years ago and have been following the patients for quite a long time,” Dr. Kirkham, a consultant rheumatologist at Guy’s and St. Thomas’ NHS Foundation Trust, London, told this news organization.
Dr. Bruce Kirkham
“We’re still seeing patients with the same type of syndrome presenting occasionally. It’s not a very common adverse event, but we think it continues,” he observed.
“Most of them don’t have very severe problems, and a lot of them can be treated with quite simple drugs or, alternatively, reducing the frequency of the injection,” Dr. Kirkham added.
Characterizing the MSK symptoms
Of 470 patients with atopic dermatitis who started treatment with dupilumab at Guy’s and St. Thomas’ NHS Foundation Trust between October 2018 and February 2021, 36 (7.65%) developed rheumatic symptoms and were referred to the rheumatology department. These individuals had their family history assessed and thorough MSK evaluations, which included antibody and inflammatory markers, ultrasound of the peripheral small joints, and MRI of the large joints and spine.
A total of 26 (5.5%) patients – 14 of whom were male – had inflammatory enthesitis, arthritis, and/or tenosynovitis. Of the others, seven had osteoarthritis and three had degenerative spine disease.
Enthesitis was the most common finding in those with rheumatic symptoms, occurring on its own in 11 patients, with arthritis in three patients, and tenosynovitis in two patients.
These symptoms appeared 2-48 weeks after starting dupilumab treatment and were categorized as mild in 16 (61%) cases, moderate in six cases, and severe in four cases.
No specific predictors of the MSK symptoms seen were noted. Patient age, sex, duration of their atopic dermatitis, or how their skin condition had been previously treated did not help identify those who might develop rheumatic problems.
Conservative management approach
All patients had “outstanding” responses to treatment, Dr. Kirkham noted: The mean Eczema Area and Severity Index score before dupilumab treatment was 21, falling to 4.2 with treatment, indicating a mean 80% improvement.
Co-author Joseph Nathan, MBChB, of London North West Healthcare NHS Trust, who collaborated on the research while working within Dr. Kirkham’s group, said separately: “The concern that patients have is that when they start a medication and develop a side effect is that the medication is going to be stopped.”
Clinicians treating the patients took a conservative approach, prescribing NSAIDs such as cyclooxygenase-2 inhibitors or altering the frequency with which dupilumab was given.
With this approach, MSK symptoms resolved in 15 patients who remained on treatment and in seven who had to stop dupilumab. There were four patients, however, who had unresolved symptoms even once dupilumab treatment had been stopped.