Cyclophosphamide is associated with long‐term treatment‐free remission in patients with pemphigus

BACKGROUND AND OBJECTIVE: Pemphigus treatment has seen significant advancements, yet long-term remission remains a challenge. Comparative data on the long-term effectiveness of available therapies are limited. We compared 10-year relapse rates in pemphigus patients treated with azathioprine or cyclophosphamide plus high-dose IV corticosteroids PATIENTS AND METHODS: In this retrospective single-center cohort study, we analyzed 91 patients with pemphigus vulgaris/foliaceus treated between 1985 and 2022. 43 patients received oral azathioprine, 48 received intermittent intravenous and oral cyclophosphamide. All patients also received intermittent high-dose IV corticosteroids for ≥ 1 year. As rituximab became widely available only after 2019, follow-up was insufficient to include it in this analysis. RESULTS: Remission occurred equally quickly in both groups, but patients treated with cyclophosphamide suffered from significantly fewer relapses: 27% of cyclophosphamide patients had ≥ 1 relapse vs. 80.6% with azathioprine (p < 0.001). 70% of cyclophosphamide patients remained relapse-free and were off therapy for an average of 7 years. CONCLUSIONS: Aggressive initial immunosuppressive therapy with cyclophosphamide is associated with a significantly lower long-term relapse rate in pemphigus. While routine use is limited by its toxicity, these findings underscore the potential for durable remission and the importance of long-term disease control as a treatment goal.