Phase 1/2 Study of Treatment of Refractory Acute Graft-Versus-Host Disease After First Line Therapy by Sequential Infusion of Expanded In-Vitro Allogenic Mesenchymal Stem Cell

1. Ethical considerations:

• The study will be conducted in accordance with the requirements expressed in the Declaration of Helsinki (Hong Kong revision, September 1989) and following the recommendations of the Good Clinical Practice of the Clinical Trials (document 111/3976/88, July 1990 ) and Spanish legislation (Royal Decree 561/1993, published in April 16th Official State Bulletin "BOE"; May 13th, 1993) laying down the requirements for conducting clinical drug trials.
• Every subject will receive a written document called "Patient Information Sheet" that contains information about the following aspects of clinical trial: a) Aim of the study, methodology, study treatment and alternative therapies, expected benefits for himself or society, risks of the study and possible adverse events, number of visits and additional tests.

b) Voluntary nature of their participation and ability to withdraw at any time, without thereby altering the doctor-patient relationship.

c) People who have access to the data of the volunteer and how they maintain the confidentiality of the data.

d) How to contact with the investigator if necessary.

• The investigator will obtain the informed consent of the subject or, failing that, from a legal representative. The subject is preferably expressed written consent or, alternatively, orally to the research team independent witnesses who declare in writing under its responsibility.
• The person participating in the clinical trial or his representative may revoke the consent at any time.

2. Data Access: