The study is an interventional, multicentre, prospective, randomized, controlled, single-blind, comparative trial of two processes for adjusting the inhibitor of calcineurin (CNI) dosage in lung transplant recipients. Recipients will be stratified by transplant center and according to the underlying lung disease (affected with cystic fibrosis or not) and will be randomized to either evaluation of calcineurin activity (CN-a) in combination with CNI blood levels versus CNI blood levels alone in a 1:1 ratio. The objective is to compare the proportion of acute rejection that has required a specific curative treatment at 6 months after transplantation between patients in the two groups.

Inclusion Criteria:

• Patient placed on the national waiting list for lung transplantation
• First de novo lung transplantation (single or double LTx)
• Prevention of allograft rejection by a usual immunosuppressive regimen including CNI (cyclosporine or tacrolimus)

Exclusion Criteria:

• Previous lung transplantation or other solid organ transplantation
• Combined lung transplantation with either liver or renal transplantation