Characteristics and clinical course of lymphangioleiomyomatosis (LAM) in patients treated with sirolimus in France

LAM is a rare multi-cystic lung disease for which treatment with sirolimus is indicated in cases of moderate or severe lung disease or declining lung function. The aim of this study was to describe patients treated with sirolimus for LAM and their outcome. This retrospective observational study was based on data from the French national health data system (SNDS). All adult women receiving sirolimus were identified in France between 2014 and 2021. In the absence of a specific LAM code in the system, an algorithm was developed to identify patients treated for possible LAM (exclusion of other sirolimus indications (transplantation, graft-versus-host disease), or probable LAM (among LAM patients hospitalized for pneumothorax, pleural drainage, pleurisy, ascites, chronic respiratory failure, lung transplantation or angiomyolipoma). 1,800 adult women had at least one delivery of sirolimus during the defined period. 1,162 patients treated for another indication for sirolimus were excluded (transplantation, graft-versus-host disease) (table). Lung transplant was performed in 17 patients post-initiation of sirolimus, including 16 with probable LAM. This study based on real-life data shows a death rate of 12-23% at 5 years following initiation of sirolimus therapy for LAM patients. <table-wrap><object-id>erj;64/suppl_68/OA1062/TB1</object-id><object-id>T1</object-id><object-id>TB1</object-id><table><colgroup><col></col><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td>Possible LAM</td><td>Probable LAM</td><td>Patients with TSC</td></tr><tr><td>Population</td><td>638</td><td>208</td><td>33</td></tr><tr><td>Mean (±SD) age, years</td><td>49.3±17.4</td><td>46.4±16.7</td><td>41.1±15.4</td></tr><tr><td>Mean (±SD) follow-up, years</td><td>3.6±2.5</td><td>3.7±2.8</td><td>4.6±2.7</td></tr><tr><td>Referral to a center of reference</td><td>44.8%</td><td>54.8%</td><td>48.5%</td></tr><tr><td>Mean (±SD) duration of sirolimus treatment</td><td>2.0±2.4</td><td>2.9±2.8</td><td>3.7±2.7</td></tr><tr><td>Death rate at 5 years after sirolimus initiation</td><td>12%</td><td>16%</td><td>23%</td></tr></tbody></table></table-wrap>