The invention relates to cyclosporine formulations for use in the prevention or treatment of pulmonary chronic graft rejection. In particular, the invention provides a cyclosporine liquid formulation for use as an aerosol for inhalation in a method of preventing or treating pulmonary chronic graft rejection in single lung transplanted patients. The formulation is preferably administered once or twice daily. The formulation may be aerosolized with a nebulizer that comprises features for monitoring the time, date and duration of inhalation by the patient, in order to monitor patient adherence. The formulation according to the invention may be combined with standard immunosuppressants and corticosteroids.