About steroid-resistant or corticosteroid-dependent aGvHD
Formerly called bone marrow transplant, Hematopoietic Stem Cell Transplantation (HSCT) is the last therapeutic option for patients with certain blood cancers or severe immunodeficiency. In practice, the treatment is designed to replace the diseased blood cells of the patient with the hematopoietic stem cells of a matching donor (allograft).
Once grafted, these stem cells will produce new healthy and functional blood cells, including white blood cells that will allow patients to bridge their immune deficiency or to eliminate surviving cancer cells.
If this technique has made considerable progress in 60 years, half of transplant recipients are still victims of complications: side effects of conditioning pretreatment (that aims to prevent transplant rejection), long-term susceptibility to infections and GvHD. In the latter case, the donor’s over-active T-cells «turn against» the patient’s tissues: mucous membranes, skin, gastro-intestinal tract, liver and lungs. The acute form appears just after the transplant, the chronic form occurring several months later (preceded or not by an acute GvHD episode).
Affecting between 30 to 50% of patients, GvHD is the main complication of hematopoietic stem cell transplantation. To halt this disease, physicians use corticosteroids. The fact remains that some 30 to 50% of aGvHD patients are refractory or dependent to the steroid treatment.
To date limited therapeutic options are available for these patients with no standard treatment approved so far in Europe and only one in the US.