5 Headlines You Missed in August 2026

August 2026 was a landmark month for rheumatology, delivering 2 FDA approvals, a pair of consequential phase 3 readouts, and a clinically important safety dataset that will shape JAK inhibitor prescribing in high-risk rheumatoid arthritis (RA). The first and most far-reaching approval came on September 1, when the FDA approved brepocitinib (Lisraya; Priovant Therapeutics) — an oral, once-daily JAK/TYK2 inhibitor — as the first agent specifically studied and approved for dermatomyositis in adults, filling a gap in a disease historically managed with therapies developed for other conditions. The second approval, granted August 19, established garetosmab-grts (Pasatru; Regeneron) as the first treatment demonstrated to reduce new heterotopic ossification lesions and clinician-assessed flare-ups in adults with fibrodysplasia ossificans progressiva, one of the rarest and most disabling disorders in rheumatology, with approximately 900 confirmed diagnoses worldwide.

On the trial data front, August delivered both momentum and a cautionary signal. The phase 3 ALKIVIA trial showed that efgartigimod alfa and hyaluronidase-qvfc (VYVGART Hytrulo; argenx) produced a 15.4-point greater improvement in mean Total Improvement Score at week 52 vs placebo (P =.0011) in autoimmune myositis, including the first positive phase 3 result specifically in immune-mediated necrotizing myopathy — a subtype with no approved therapy. Sonelokimab, the IL-17A/F Nanobody from MoonLake Immunotherapeutics, met its primary ACR50 endpoint and all key secondary endpoints at week 16 in biologic-naïve patients with active psoriatic arthritis in the phase 3 IZAR-1 trial (ACR50, 42.1%; ACR20, 66.5%; MDA, 41.2%; PASI90, 61%), advancing a regulatory-submission-ready program. Tempering the month’s positive signals, pooled data from the FDA-mandated RA-BRIDGE and RA-BRANCH post-marketing safety trials presented at EULAR 2026 showed that baricitinib failed to demonstrate noninferiority to TNF inhibitors for VTE risk in patients with RA enriched for thromboembolic risk factors (HR, 1.61; 95% CI, 0.97–2.66), with the upper confidence bound exceeding the prespecified margin — a finding with direct prescribing implications for the significant proportion of RA patients who carry VTE risk factors.

Check out this August 2026 rheumatology month in review for full coverage of these stories and more.

1. FDA Approves First Oral Treatment of Dermatomyositis in Adult Patients

Brepocitinib (Lisraya; Priovant Therapeutics), an oral, once-daily JAK/TYK2 inhibitor, received FDA approval for the treatment of dermatomyositis in adults — the first agent specifically studied and approved for the condition, which has historically been managed with corticosteroids, IVIg, and immunosuppressants developed for other diseases. The approval was supported by a phase 3 randomized, double-blind, placebo-controlled trial of 241 adults with dermatomyositis, in which both the 30 mg and 15 mg once-daily doses were evaluated against placebo over 52 weeks using the Total Improvement Score as the primary endpoint. Lisraya received both Orphan Drug and Priority Review designations from the FDA ahead of the approval.

2. FDA Approves Garetosmab-grts for Fibrodysplasia Ossificans Progressiva

Garetosmab-grts (Pasatru; Regeneron Pharmaceuticals), a fully human monoclonal antibody that blocks Activin A — a protein Regeneron scientists identified as critical to heterotopic ossification formation in FOP — received FDA approval August 19, 2026, to reduce new HO lesions and clinician-assessed flare-ups in adults with fibrodysplasia ossificans progressiva. The approval is supported by the phase 3 OPTIMA trial, in which both the 3 mg/kg and 10 mg/kg doses were highly efficacious in reducing the total number and volume of new HO lesions at 56 weeks vs placebo; the recommended starting dosage is 10 mg/kg IV every 4 weeks, with an option to reduce to 3 mg/kg if not tolerated. A phase 3 trial in adolescents and children with FOP, OPTIMA 2, is planned to begin later in 2026, and the therapy can be administered across care settings including home infusion.

3. ALKIVIA: Efgartigimod Improves Myositis, Hits Phase 3 Primary End Point

Efgartigimod alfa and hyaluronidase-qvfc (VYVGART Hytrulo; argenx), a subcutaneous FcRn inhibitor that reduces pathogenic IgG autoantibodies, met the primary endpoint of the phase 3 ALKIVIA trial — producing a 15.4-point greater improvement in mean Total Improvement Score at week 52 vs placebo (47.95 vs 32.56; P =.0011) in 264 adults with active autoimmune myositis on background treatment, including both IMNM and DM subtypes. The IMNM subgroup alone also met the primary endpoint, with a 14.8-point greater improvement in mean TIS vs placebo — the first positive phase 3 result in immune-mediated necrotizing myopathy, a disease with no currently approved therapy. Treatment separation from placebo emerged early and was sustained through the full 52 weeks, with a consistent safety profile and no new signals identified.

4. Sonelokimab Meets All End Points in Phase 3 IZAR-1 PsA Trial

Sonelokimab, an IL-17A/F Nanobody from MoonLake Immunotherapeutics, met its primary endpoint of ACR50 at week 16 in biologic-naïve adults with active psoriatic arthritis in the phase 3 IZAR-1 trial (42.1% with induction), with all key secondary endpoints also met — including ACR20 (66.5%), minimal disease activity (41.2%), and PASI90 among patients with concomitant skin involvement (61%). Significant improvements were also observed in patient-reported outcomes and physical function, including HAQ-DI and SF-36 Physical Component Summary score, supporting a broad multidomain efficacy profile across musculoskeletal symptoms, skin disease, and function. IZAR-1 will remain blinded and continue through week 52, with a full readout expected in H1 2027; the parallel IZAR-2 trial in TNFi-inadequate responders is targeting enrollment completion in Q3 2026.

5. Baricitinib Misses VTE Noninferiority vs TNFi in High-Risk RA

Pooled long-term data from the FDA-mandated RA-BRIDGE and RA-BRANCH post-marketing safety trials, presented at EULAR 2026, showed that baricitinib did not demonstrate noninferiority to TNF inhibitors for VTE risk in patients with RA enriched for thromboembolic risk factors, with a hazard ratio of 1.61 (95% CI, 0.97–2.66) for combined baricitinib doses vs TNFi and the upper confidence bound exceeding the prespecified noninferiority margin of 1.8. Serious infections, including new-onset COVID-19, were also significantly more frequent with baricitinib in the pooled analysis. The trials were specifically designed to enrich for risk by enrolling older patients and those with obesity, prior VTE, or multiple cardiovascular risk factors — making the finding directly applicable to the subset of RA patients in whom JAK inhibitor VTE risk is most clinically relevant.

References

1. Johnson V. FDA Approves First Oral Treatment of Dermatomyositis in Adult Patients. RheumatologyLive. September 1, 2026. https://www.rheum-live.com/view/fda-approves-first-oral-treatment-of-dermatomyositis-in-adult-patients

2. Johnson V. FDA Approves Garetosmab-grts for Fibrodysplasia Ossificans Progressiva. RheumatologyLive. August 19, 2026. https://www.rheum-live.com/view/fda-approves-garetosmab-grts-for-fibrodysplasia-ossificans-progressiva

3. Johnson V. ALKIVIA: Efgartigimod Improves Myositis, Hits Phase 3 Primary End Point. RheumatologyLive. August 17, 2026. https://www.rheum-live.com/view/alkivia-efgartigimod-improves-myositis-hits-phase-3-primary-end-point

4. Johnson V. Sonelokimab Meets All End Points in Phase 3 IZAR-1 PsA Trial. RheumatologyLive. August 10, 2026. https://www.rheum-live.com/view/sonelokimab-meets-all-endpoints-phase-3-izar-1-psa-trial

5. Johnson V. Baricitinib Misses VTE Noninferiority vs TNFi in High-Risk RA. RheumatologyLive. August 6, 2026. https://www.rheum-live.com/view/baricitinib-misses-vte-noninferiority-vs-tnfi-high-risk-ra