Real-world experience with obinutuzumab in difficult-to-treat myositis: concise report of a case series
Authors' conclusion
Obinutuzumab was safe and provided durable improvement in difficult-to-treat myositis patients with rituximab allergy, further highlighting targeting the B-cell pathway.
Study context
- Population
- Difficult-to-treat idiopathic inflammatory myopathy (IIM) patients treated with obinutuzumab, Northwell Rheumatology database (2019–24); 2 ASyS, 1 dermatomyositis (DM), 2 overlap myositis
- Participants
- 5 case series
- Outcome
- Overall response (complete, partial or no response) based on clinical response and PGA
Methodological detailssingle-group, descriptive statistics, Total improvement score not calculated because data were collected retrospectively
- Single-group
- Descriptive statistics
- Total improvement score not calculated because data were collected retrospectively
Main finding
As reported in the abstract
Overall improvement · 3-6 months
Obinutuzumab
80%
Observational data: associations, not effects.
Further findings
Complete response at last observation
- Complete response
- 4/5 patients
Respiratory status in interstitial lung disease (ILD) patients
- Respiratory status improved/stabilized in all ILD patients
Second obinutuzumab cycle required
- Second cycle required (one for recurrence, one for persistent disease with B cell re-population)
- Two patients
- One lost to follow-up after the second cycle, deemed a non-responder
Safety
Hypogammaglobulinaemia, significant infections or hospitalisations
- None observed
Original publication
Real-world experience with obinutuzumab in difficult-to-treat myositis: concise report of a case series. Rheumatology (Oxford). Published 25 August 2026. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →