Ruxolitinib for Bronchiolitis Obliterans Syndrome after Allogeneic Hematopoietic Stem Cell Transplantation

• Published in: Blood 2021-11, Vol.138 (Supplement 1), p.3899-3899
• Main Authors: Kulagin, Egor A., Volkova, Alisa G., Dotsenko, Anna A., Yanbukhtina, Valeria R., Rabik, Julia D., Smirnova, Anna G., Golubovskaya, Irina K., Trofimov, Vasiliy I., Moiseev, Ivan S.
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2021-153548

Introduction: Bronchiolitis obliterans syndrome (BOS) is an extremely unfavorable chronic GVHD manifestation with limited therapeutic options. Recent small retrospective series and the only prospective randomized trial have demonstrated different response rates (8.6 - 66.7%) in patients with BOS to JAK1/2 inhibitor ruxolitinib (Streiler C. et al. BMT 2020, Zhao Y. et al. Front. Pharmacol. 2021, Zeiser R. et al. NEJM 2021). Here we report a single-center study of the ruxolitinib efficacy for BOS in adults after HSCT. Methods: The study included 52 patients (median age 33 years (18-58), female 48%) diagnosed with BOS according to the NIH (2014) criteria between 2008 and 2020. The median %FEV1 at BOS diagnosis was 41.6% (20.0-74.1). Severe BOS was present in 44% patients. Due to the previous extrapulmonary cGVHD, the vast majority of patients (81%) had a history of various treatment options, including calcineurin inhibitors, systemic steroids, extracorporeal photopheresis (ECP), tyrosine kinase inhibitors (TKIs imatinib, dasatinib) and ruxolitinib. After BOS diagnosis the following treatments were administered: a FAM-like regimen (fluticasone, azithromycin and montelukast) (94%), CNIs (50%), mTOR inhibitor (35%), systemic corticosteroids (52%), ECP (25%) or low-dose rIL-2 (19%) as the first and subsequent lines of therapy. Seventeen patients (33%) received TKIs. A total of 20 BOS patients received ruxolitinib (median dose of 15 mg/day). The remaining 32 patients were included in the control group. The response was assessed by the dynamics of FEV1 according to the NIH scale (2014): partial response (PR, ≥10% increase in FEV1), stabilization (