Biomedical subjects
Publications and source records attributed to J A Snowden.
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Experimental data and early phase I/II studies suggest that high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HSCT) can arrest progression of severe autoimmune diseases. We have evaluated the toxicity and disease response in 473 patients with severe autoimmune disease treated with autologous HSCT between 1995 and 2003, from 110 centers participating in the European Group for Blood and Marrow Transplantation (EBMT) autoimmune disease working party database. Survival, transplant-related mortality, treatment response and disease progression were assessed. In all, 420 patients (89%; 86+/-4% at 3 years, median follow-up 20 months) were alive, 53 (11%) had died from transplant-related mortality (N=31; 7+/-3% at 3 years) or disease progression (N=22; 9+/-4% at 3 years). Of 370 patients, 299 evaluable for response (81%) showed a treatment response, which was sustained in 213 (71% of responders). Response was associated with disease (P<0.001), was better in patients who received cyclophosphamide during mobilization (relative risk (RR)3.28 (1.57-6.83)) and was worse with increasing age (>40 years, RR0.29 (0.11-0.82)). Disease progression was associated with disease (P<0.001) and conditioning intensity (high intensity, RR1; intermediate intensity, RR1.81 (0.96-3.42)); low intensity, RR2.34 (1.074-5.11)). These data from the collective EBMT experience support the hypothesis that autologous HSCT can alter disease progression in severe autoimmune disease.
The potential of haemopoietic stem cell transplantation (HSCT) for the treatment of autoimmune and inflammatory diseases was originally supported by almost three decades of animal experiments and by the serendipitous remissions of autoimmune disease observed in patients undergoing transplantation for haematological disorders. Improved safety of both autologous and allogeneic HSCT over the last decade has been followed by increasing acceptance of HSCT as an experimental treatment for severe autoimmune diseases that are resistant to conventional treatment. International databases have collated over 700 procedures performed specifically for a variety of autoimmune diseases. Phase III clinical trials are in progress for some diseases. This review provides a comprehensive update on the efficacy and toxicity of HSCT in severe autoimmune disease. Future directions in the context of other evolving therapies are discussed.
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Cardiac failure is a known complication of haemopoietic stem cell transplantation (HSCT) and is often difficult to diagnose as patients may have multiple medical problems. Since brain natriuretic peptide (BNP) is largely a hormone of cardiac ventricular origin and is released early in the course of ventricular dysfunction, we have examined the value of serial plasma BNP levels for detecting cardiac failure in patients undergoing cytotoxic conditioning for HSCT. Fifteen patients undergoing HSCT were evaluated (10 undergoing autologous HSCT; five undergoing allogeneic HSCT). BNP was measured by radioimmunoassay prior to therapy and weekly for 5 weeks. Seven patients had a significant rise in BNP level (above a previously established threshold of 43 pmol/l associated with cardiac failure), occurring 1-4 weeks post commencement of conditioning. In three of these patients, cardiac failure was subsequently diagnosed clinically 3, 9 and 23 days after a BNP level of 43 pmol/l had been detected. These three patients had the highest peak BNP levels for the group and in each case elevation in BNP level occurred for a period exceeding 1 week. Although numbers were relatively small, a BNP >43 pmol/l was significantly associated with the inclusion of high-dose cyclophosphamide in the preparative regimen (P = 0.02). BNP levels showed no relationship to febrile episodes. In conclusion, these results show that plasma BNP may be used as a marker for early detection of cardiac dysfunction in patients undergoing HSCT, particularly if levels are increased for periods exceeding 1 week. Measurement of BNP during HSCT may be helpful in patients at risk of cardiac failure, in complex clinical situations and in monitoring the cardiotoxicity of preparative regimens.
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Autologous stem cell transplantation (ASCT) is starting to be investigated as a potential therapy for severe refractory autoimmune disease including rheumatological, neurological and haematological diagnoses. Increasing numbers of cases are now reported in the literature. Data from all transplanted patients are being collated in a centralized register by the European Group for Blood and Marrow Transplantation (EBMT) and the European League against Rheumatism (EULAR) to enable effective evaluation of the safety and efficacy of this promising technique. Thus far, results have been encouraging; however, more treatment-related deaths were reported in multiorgan diseases such as scleroderma and less in diseases such as rheumatoid arthritis, which confirms the importance of careful patient selection. Optimization of mobilization, conditioning regimen and graft manipulation is required to maximize efficacy without increasing mortality and morbidity. The use of maintenance therapy after ASCT in order to prevent relapse needs to be explored. Following individual case reports and small cohort studies, the next step is likely to involve multicentre randomized controlled trials.
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OBJECTIVE: Based on animal studies and anecdotal case reports, high-dose therapy and autologous blood stem cell rescue have been proposed as an experimental treatment for severe, refractory rheumatoid arthritis (RA). This study aimed to establish the toxicity of this treatment and obtain preliminary efficacy data upon which to base future clinical trials. METHODS: Two cohorts of 4 patients who fulfilled criteria for severe, active, treatment-resistant RA were recruited into a dose-escalation study of cyclophosphamide (CYC) (100 mg/kg or 200 mg/kg) followed by unmanipulated peripheral blood stem cell rescue. Patient treatment was managed according to a standard supportive care protocol. Disease-modifying drugs were discontinued before treatment, but corticosteroids were maintained and later tapered where possible. Patients' conditions were assessed using World Health Organization toxicity criteria and standard parameters for rheumatic disease. RESULTS: Dose-dependent differences in hematologic toxicity were observed between cohorts 1 and 2, although toxicity was similar for other systems and was most significant in the gastrointestinal system. Patients in cohort 1 had only transient responses to therapy, lasting 2-3 months. Substantial improvements were sustained beyond 17-19 months in cohort 2, including steroid-independent disease remission for 1 patient, although the procedure did not completely abolish disease activity. CONCLUSION: High-dose CYC and unmanipulated autologous blood stem cell rescue has acceptable dose-dependent toxicity in severe, treatment-resistant RA, and 200 mg/kg of CYC induces substantial clinical responses. Refinement of this intensive approach might include further intensification of the preparation regimen, graft manipulation, and posttransplant immunomodulation.
This ongoing multicentre prospective phase I/II trial enrolled 74 consecutive patients from 22 centres worldwide with severe autoimmune disease, 35 with rheumatological disorders, 31 with neurological, five with haematological and three with vasculitides. They were treated with autologous peripheral blood or bone marrow transplants according to predetermined criteria. Two patients died after mobilisation before transplant. Seventy-two patients were given 73 transplants, seven bone marrow, and 66 mobilised peripheral blood stem cell transplants. The graft was manipulated to remove T and/or B cells in 43 cases. All 73 transplants engrafted. Five patients died of transplant-related complications: two from bleeding, three from infections. Two patients died of progressive disease. The transplant-related mortality at 1 year of 9% (1-17%; 95% CI) is comparable to the transplant-related mortality of 6% (3-9%; 95% CI) in patients transplanted during the same period in Europe for non-Hodgkin's lymphoma in sensitive relapse (P = 0.39). Sixty patients are evaluable for response, 40 patients (65%) showed some improvement in their disease. Haematopoietic stem cell transplants are feasible for patients with severe refractory autoimmune disease. Transplant-related mortality is comparable to results in patients with non-Hodgkin's lymphoma in responsive relapse. Two-thirds of the patients show at least some response. These preliminary data are promising. Although associated with considerable risk, randomised trials comparing autologous stem cell transplants to conventional therapy are warranted.
OBJECTIVES: Autologous haemopoietic stem cell transplantation (HSCT), which carries defined risks of early treatment-related mortality (TRM), has recently been proposed as an experimental therapy for severe rheumatoid arthritis (RA). The aim of this study was to establish whether the risks of this approach are acceptable to patients with RA and whether risk taking related to disease-associated or personal/social parameters. METHODS: A standard gamble questionnaire was used to determine the acceptable risk of mortality for a potentially curative procedure in patients with RA aged <70 yr. Additional data collected included age, sex, duration of RA, number of second-line agents, domestic and workforce information, and self-assessed disability. RESULTS: The 53 patients (age range 24-69 yr, 39 female, 14 male, disease duration 2-43 yr) interviewed were prepared to accept a broad range of treatment-related mortality in order to be returned to normality off all drugs (median 5%, range 0-50%). Risk taking was significantly related to degree of disability measured by the disability section of the Health Assessment Questionnaire (HAQ; P = 0.001) and negatively related to age (P = 0.04), although only HAQ score maintained significance on multivariate analysis. Using linear regression, we were able to determine that current TRM of autologous HSCT in Australia (3.3%) would be acceptable to patients with HAQ scores of >0.44 (84% of our sample), but allogeneic HSCT (with a TRM of 13.1%) would be acceptable only to severely disabled patients with HAQ scores of >2.45 (4% of our sample), assuming the procedure to be curative. CONCLUSION: Along with previous studies, these results suggest that, if long-term efficacy can be proven, then the risks of autografting may be acceptable to most patients with RA, particularly those with significant disability.
The concept of using hematopoietic stem cell transplantation to treat patients with autoimmune disease was first provided by animal studies and anecdotal case reports. Advances over recent years in autologous hematopoietic stem cell transplantation, most notably cytokine-mobilized peripheral blood stem cells, have been followed by its specific use to treat severe autoimmune and inflammatory diseases. Guidelines have been published, and, by March 1999, 150 cases were registered with the International Autoimmune Disease Stem Cell Project Database. This review summarizes the literature published with respect to inflammatory rheumatic disease over the past few years and discusses future directions aimed at refining this intensive approach.
OBJECTIVE: To investigate the long-term outcome of autoimmune disease following allogeneic bone marrow transplantation (BMT), and its relationship to hemopoietic chimerism. METHODS: Three previously described patients with rheumatoid arthritis (RA) who underwent allogeneic BMT for therapy-related severe aplastic anemia and 1 new patient with psoriasis who received BMT for chronic myeloid leukemia (CML) were followed up. Molecular studies were performed to assess hemopoietic and immune reconstitution in 3 cases. RESULTS: In 2 of the RA patients, the RA remained in remission without treatment, with nonprogressive disease, 11 and 13 years after BMT. The third patient with RA had a relapse 2 years after BMT, although the previously aggressive disease subsequently ran an attenuated course with treatment-free remission for the last 11 years. Comparison with other cases of RA suggests that graft-versus-host disease may influence the long-term outcome, perhaps through ongoing inhibition of the immune system. In the patient with psoriasis, BMT was followed by remission, but the psoriatic rash recurred and arthropathy developed 12 months later. The psoriasis and arthropathy remained active 4.5 years post-BMT, although the CML remained in remission. Molecular studies in the 2 patients whose RA remained in continued remission and in the patient with psoriasis that relapsed confirmed complete donor hemopoietic reconstitution. CONCLUSION: Long-term followup of autoimmune disease after allogeneic transplantation confirmed cure of the autoimmune disease in some, but eventual relapse in others. The occurrence of relapse despite complete donor hemopoietic reconstitution is evidence for the development of de novo, as opposed to persistent, disease, and is possibly related to intrinsic susceptibility of the transplanted stem cells or to host factors. There may be a relationship between remission of autoimmune disease and graft-versus-host reaction. These findings have relevance for the evolving application of stem cell transplantation as a therapy for autoimmune diseases.
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Autologous haemopoietic stem cell transplantation (HSCT) represents a potential therapy for severe rheumatoid arthritis (RA). As a prelude to clinical trails, the safety and efficacy of haemopoietic stem cell (HSC) mobilisation required investigation as colony-stimulating factors (CSFs) have been reported to flare RA. A double-blind, randomised placebo-controlled dose escalation study was performed. Two cohorts of eight patients fulfilling strict eligibility criteria for severe active RA (age median 40 years, range 24-60 years; median disease duration 10.5 years, range 2-18 years) received filgrastim (r-Hu-methionyl granulocyte(G)-CSF) at 5 and 10 microg/kg/day, randomised in a 5:3 ratio with placebo. Patients were unblinded on the fifth day of treatment and those randomised to filgrastim underwent cell harvesting (leukapheresis) daily until 2 x 10(6)/kg CD34+ cells (haemopoietic stem and progenitor cells) were obtained. Patients were assessed by clinical and laboratory parameters before, during and after filgrastim administration. RA flare was defined as an increase of 30% or more in two of the following parameters: tender joint count, swollen joint count or pain score. Efficacy was assessed by quantitation of CD34+ cells and CFU-GM. One patient in the 5 microg/kg/day group and two patients in the 10 microg/kg/day group fulfilled criteria for RA flare, although this did not preclude successful stem cell collection. Median changes in swollen and tender joint counts were not supportive of filgrastim consistently causing exacerbation of disease, but administration of filgrastim at 10 microg/kg/day was associated with rises in median C-reactive protein and median rheumatoid factor compared with placebo. Other adverse events were well recognised for filgrastim and included bone pain (80%) and increases in alkaline phosphatase (four-fold) and lactate dehydrogenase (two-fold). With respect to efficacy, filgrastim at 10 microg/kg/day was more efficient with all patients (n = 5) achieving target CD34+ cell counts with a single leukapheresis (median = 2.8, range = 2.3-4.8 x 10(6)/kg, median CFU-GM = 22.1, range = 4.2-102.9 x 10(4)/kg), whereas 1-3 leukaphereses were necessary to achieve the target yield using 5 microg/kg/day. We conclude that filgrastim may be administered to patients with severe active RA for effective stem cell mobilisation. Flare of RA occurs in a minority of patients and is more likely with 10 than 5 microg/kg/day. However, on balance, 10 microg/kg/day remains the dose of choice in view of more efficient CD34+ cell mobilisation.