Preventive therapeutic intervention by L-CsA is primarily aimed to suppress T-lymphocyte suppression and inflammatory responses and secondly to prevent fibrotic effects making it more likely to be effective in early stages of BOS. Early development of BOS, which mostly will not be diagnosed, and acute organ rejections are strongly patho-physiological associated. Prevention of the very early development of chronic rejection by L-CsA post LTX may be the ideal starting point for IMP application.