To evaluate, under usual clinical practice conditions and with a 12-month follow-up , the most relevant pharmacokinetic parameters of tacrolimus metabolism and safety, in patients with recent lung transplant (unilateral or bilateral) treated with LCPT.

Inclusion Criteria:

• Patients ≥18 years old.
• Patients who have received a first unilateral or bilateral lung transplant.
• Patients who have started oral treatment with tacrolimus using the LCPT formulation, with a once-daily dosage within the first 3 months post-transplant.
• Patients with a treatment duration expected to be ≥12 months.
• The patient (or their representative) can sign the informed consent to participate in the study.

Exclusion Criteria:

• Patients who have received a multi-organ transplant or have a history of any organ transplant, including lung.
• Patients with an estimated survival of <12 months
• Patients diagnosed with cystic fibrosis
• Patients diagnosed with scleroderma.
• Patients diagnosed with a systemic disease affecting the digestive system.
• Patients in any situation or condition that, in the investigator's opinion, makes participation inadvisable, such as any treatment that may interfere with the study.
• Patients who are participating or have participated in an interventional research study within 30 days prior to inclusion.
• Pregnant women, those planning to become pregnant, or those who are breastfeeding.
• Patients who are unable to complete the study.
• Patients who have not signed the informed consent.

Patients after a first unilateral or bilateral lung transplant start treatment with rapid-release tacrolimus every 12 hours (IR-Tac formulation) and, after achieving a stable dose and before 3 months, switch to once-daily LCPT tacrolimus. These treatments will have been prescribed by the investigator following usual clinical practice, with no relation to inclusion in this study.