This post-marketing surveillance study is to investigate the efficacy and safety of azathioprine tablets in subjects whom lung transplantation is performed.

Inclusion Criteria:

• Subjects who undergo lung transplantation and azathioprine tablets were administered

Exclusion Criteria:

• Subjects with hypersensitivity to the ingredients of azathioprine tablet
• Subjects who is pregnant or might be pregnant
• Subjects whose white count is lower than 3000/cubic millimeter

The following subjects to whom azathioprine tablet is administered for "the suppression of lung transplant rejection";

1. Subjects on whom lung transplantation is performed after approval and to whom azathioprine tablet is administered from transplant surgery to May 2010.
2. Subjects on whom lung transplantation is performed before approval and who have already completed the drug administeration as well as during the drug administration at the time of the contract terminiation.