Disease progression in patients with the restrictive and mixed phenotype of Chronic Lung Allograft dysfunction-A retrospective analysis in five European centers to assess the feasibility of a therapeutic trial.

The poor outcome of these two specific CLAD phenotypes suggests the urgent need for future therapeutic randomized trials. The number of missing values in a potential trial seems to be high and most frequently attributed to death. Survival may be used as an endpoint in clinical trials in these distinct phenotypes and imputation techniques are relevant if graft function is used as a surrogate of disease progression in future trials.