Long-Term Safety and Efficacy of Lenabasum, a Cannabinoid Receptor Type 2 Agonist, in Patients with Dermatomyositis with Refractory Skin Disease: Follow-Up Data from a 3-Year Open-Label Extension Study.

UNLABELLED: Dermatomyositis (DM) is a rare autoimmune condition involving skin manifestations often resistant to standard treatments such as immunosuppressants and antimalarials. Biopsies show elevated inflammatory cells such as CD4+ T cells, dendritic cells, and cytokines. Lenabasum, a selective cannabinoid receptor 2 agonist, has demonstrated significant benefits in treating autoimmune skin diseases.

OBJECTIVES

This study utilizes data from the open-label extension (OLE) phase of the lenabasum phase 2 trial and additional post-OLE follow-up data. Key aims include evaluating the drug's long-term effectiveness and assessing disease manifestation recurrence.

METHODS

The phase 2 lenabasum trial enrolled patients with treatment-resistant, skin-predominant DM. The OLE consisted of a 3-year period during which 20 patients were on the drug for the entire duration, with assessments every 8 weeks to evaluate drug safety and efficacy. Subsequently, a follow-up retrospective chart review was performed on patients who completed the OLE as well as on control subjects with DM who did not participate in the lenabasum trial.

RESULTS

By week 68, patients exhibited reductions in Cutaneous Dermatomyositis Disease Area and Severity Index activity score (-21.8), Patient Skin Activity Visual Analog Scale (-3.0), and Skindex-29 (-28.0) from OLE baseline. After OLE, 58.3% maintained stable disease, significantly higher than controls (P = .035), with 41.7% not experiencing flares compared with 91.6% of controls. In addition, 50% of patients reported sustained pruritus improvement.

CONCLUSIONS

Data from OLE and subsequent follow-up periods demonstrate lenabasum's efficacy in maintaining disease stability, reducing flares, and improving DM symptoms, suggesting that it is a promising option for patients with treatment-resistant skin-predominant DM.

TRIAL REGISTRATION: This study was registered at clinicaltrials.gov, with NCT02466243. Study registration was first submitted on June 2, 2015.