What Is Graft Versus Host Disease, and How Is It Treated?

In treating blood and bone marrow (hematological) cancers, the aim is to administer the highest possible doses of chemotherapy and radiotherapy to kill all cancer cells. Because this also kills healthy blood-producing cells in the bone marrow, after treatment, stem cell transplantation is used to help the patient rapidly resume production of blood components.

Allogeneic, meaning stem cell transplantation from another tissue-matched donor, transfers not only stem cells but also certain white blood cells (lymphocytes) belonging to the donor's immune system . These lymphocytes, fundamental immune cells, can enter the patient, capture cancer cells remaining despite high-dose chemotherapy and radiotherapy, and kill them. This is an important advantage of allogeneic transplantation. This effect is called the graft versus tumor effect in terminology.

This situation also carries a disadvantage:

When donor defense cells enter the patient, they may recognize healthy cells as enemies as well as cancer cells and attack them. This abnormal response most often harms the patient's skin, liver and gastrointestinal system, and is called graft versus host disease . To reduce its likelihood, medicines suppressing the immune system after stem cell transplantation, called immunosuppressants , are administered long term. Ibrutinibis the first treatment to receive FDA approval for this purpose.

Immunosuppressive medicines used to reduce graft versus host disease risk increase opportunistic infection risk by weakening immunity, so patients also receive preventive (prophylactic) antibiotics.

Graft Versus Host Disease (GVHH) Is Divided into Two Types:

1. Acute GVHH: develops within the first 3 months after transplantation and is treated with high-dose corticosteroids (cortisone).
2. Chronic GVHH: develops after preventive (prophylactic) measures or therapeutic immunosuppressive treatment following treatments such as allogeneic stem cell transplantation.

Treatment Options for Graft Versus Host Disease:

• Corticosteroids: prednisolone, hydrocortisone
• Calcineurin inhibitors: cyclosporine, tacrolimus
• Antiproliferatives: mycophenolate mofetil
• mTOR inhibitors: sirolimus
• Tyrosine kinase inhibitor: ibrutinib (the only FDA-approved treatment for this disease)