This study is a prospective, open-label, multi-center, non-comparative, observational study to assess safety and effectiveness of Jakavi® (ruxolitinib) in the real-world clinical setting in Korean Graft-versus-Host disease (GvHD) patients

The dosage and duration of treatment may be considered and decided by the investigator in accordance with prescribing information of Jakavi®. All participants who receive at least one dose of the drug and are in the follow-up assessment or early discontinuation (withdrawal) will be the safety population. This study will enroll patients who are newly starting Jakavi® and patients who have been taking Jakavi® prior to study participation. Considering the current clinical practice, a 24 weeks follow-up period of ruxolitinib treatment is needed to assess the safety and the durable effectiveness of the treatment. Mandatory additional safety monitoring will be conducted following the last dose of the treatment for further AE assessments.

Inclusion Criteria:

1. Patients who diagnosed with GvHD and currently receiving or going to receive Jakavi® treatment according to locally approved label
2. Patients who are willing to provide written informed consent prior to study enrollment

Exclusion Criteria:

1. Patients under 12 years old
2. Patients with contraindication according to locally approved label of Jakavi®
3. Patients who receive or are going to receive any investigational medicine during the observation period.

Patients who are going to receive Jakavi® for the first time or those who are currently taking Jakavi® per clinical judgment