High Dose Chemotheraphy and Stem Cell Transplantation for Rheumatoid Arthritis
Recently, three articles were published in Arthritis and Rheumatism (Nov. 1999) that reported on results of high dose chemotherapy and autologous stem cell transplantation for the treatment of severe, refractory rheumatoid arthritis. In each study, the number of patients treated was extremely small, and the procedures for treatment varied widely among the three studies.
In the first study, Breban et al (Arthritis and Rheumatism 42:2275, 1999) treated 4 patients with a single dose of cyclophosphamide (CYC) (4 gm/m2 or approximately 100 mg/kg), followed by granulocyte colony-stimulating factor (G-CSF). In the second study by Burt et al, (Arthritis and Rheumatism 42:2281, 1999) 4 patients were treated with CYC 200 mg/kg, antithymocyte globulin (90 mg/kl), and total body irradiation (in one patient). And, lastly, Snowden et al (Arthritis and Rheumatism 42:2286, 1999) treated 4 patients each with either CYC 100 mg/kg or 200 mg/kg,followed by unmanipulated peripheral blood stem cell rescue.
Despite the variable CYC doses and stem cell mobilization procedures, the results were fairly consistentthat is, although initial positive responses were observed, recurrence of disease was noted for all patients, usually within the first 12 months after treatment. Encouragingly, however, the disease seemed to be attenuated in some patients (that is, more responsive to conventional therapies).
Editorial Note: These results are discouraging in that disease recurred in all subjects despite the intensive therapy. One has to question then whether the potential risks of such therapies are justified for only temporary clinical responses such as these. Allogeneic stem cell transplantation may be preferable to autologous since allogeneic cells could conceivably play a role in eradicating abnormal immune cell populations. These issues need to be addressed. A nice editorial on these three articles in present is the same issue of Arthritis and Rheumatism by McSweeney PA, Furst DE, and West SG (Arthritis and Rheumatism 42:2269, 1999).