High-dose cyclophosphamide in multiple sclerosis patients undergoing autologous stem cell transplantation

Transplantation for autoimmune diseases in north and South America: a report of the Center for International Blood and Marrow Transplant Research

Hematopoietic cell transplantation (HCT) is an emerging therapy for patients with severe autoimmune diseases (AID). We report data on 368 patients with AID who underwent HCT in 64 North and South American transplantation centers reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2009. Most of the HCTs involved autologous grafts (n = 339); allogeneic HCT (n = 29) was done mostly in children. The most common indications for HCT were multiple sclerosis, systemic sclerosis, and systemic lupus erythematosus. The median age at transplantation was 38 years for autologous HCT and 25 years for allogeneic HCT. The corresponding times from diagnosis to HCT were 35 months and 24 months. Three-year overall survival after autologous HCT was 86% (95% confidence interval [CI], 81%-91%). Median follow-up of survivors was 31 months (range, 1-144 months). The most common causes of death were AID progression, infections, and organ failure. On multivariate analysis, the risk of death was higher in patients at centers that performed fewer than 5 autologous HCTs (relative risk, 3.5; 95% CI, 1.1-11.1; P = .03) and those that performed 5 to 15 autologous HCTs for AID during the study period (relative risk, 4.2; 95% CI, 1.5-11.7; P = .006) compared with patients at centers that performed more than 15 autologous HCTs for AID during the study period. AID is an emerging indication for HCT in the region. Collaboration of hematologists and other disease specialists with an outcomes database is important to promote optimal patient selection, analysis of the impact of prognostic variables and long-term outcomes, and development of clinical trials.

Cyclophosphamide induces mRNA, protein and enzyme activity of cytochrome P450 in rat

The effects of cyclophosphamide (CPA) on CYP enzymes in vivo and its auto induction in rat were investigated in Wistar/Fu male rats at a single dose (40 or 200 mg kg(-1)) or as repeated dose of 200 mg kg(-1) CPA. After a single dose of CPA, mRNAs of CYPs 2B1, 2B2, 3A2, 2C11 were significantly induced up to 220-, 6.7-, 5.0- and 5.8-fold at the low dose CPA, and 4800-, 52-, 22- and 2.5-fold at the high dose. CYP2B1/2 and CYP3A proteins were increased by 4- and 2-fold (low dose) and by 28- and 1.7-fold (high dose). CYP2C11 protein levels were not altered. Microsomal activities of CYP2B, CYP3A and 2C11 were increased by 2-, 1.8- and 1.3-fold at low dose CPA, and 3.2-, 1.7- and 1.6-fold at high dose. A significant (p<0.05) decrease in CPA concentration and a significant (p<0.05) increase in 4-OH-CPA levels were observed with repeated administration of CPA. Acute induction effect on CYP2B1, 2B2, 2C11 and 3A2 and a substantial up regulation of CYP2B1 mRNA were observed after a single dose of CPA, auto induction was observed by repeated administration.

The Effect of Repeated Administration of Cyclophosphamide on Cytochrome P450 2B in Rats

PURPOSE

The prodrug cyclophosphamide (CPA) is activated by cytochrome P450 (CYP) enzymes. CPA is one of the corner stones in all cancer treatment. We have studied the effect of repeated doses of CPA given at different time intervals on the mRNA, protein levels, and enzyme activity of CYPs in rats.

EXPERIMENTAL DESIGN

Two groups of animals (A-75 and A-150) were treated with four doses of CPA (75 and 150 mg/kg, respectively) at short time intervals (6 h). The third group of animals (B-150) was treated with 150 mg/kg at 24-h intervals. Three animals were killed 30 min after administration, and three animals immediately before the next dose.

RESULTS

CYP2B1 and CYP2B2 mRNAs were significantly induced at 6 h after each dose in group A-75 (maximum of 2100-fold and 60-fold after the third dose, respectively), whereas the mRNA levels measured at 6 h postadministration in group A-150 were 1,490-fold and 36-fold after the second dose. In group B-150, no significant induction of mRNA levels was observed. CYP2B1 and CYP2B2 protein levels also increased with increased mRNAs. Plasma levels of 4-hydroxy-CPA measured at 30 min after dose correlated well with the increase in protein levels.

CONCLUSION

Up-regulation of CYP2B mRNA, with a concomitant increase in protein expression and activity, were observed after repeated administration of low doses of CPA compared with that found using higher doses, possibly due to toxicity counteracting induction. These results may help in designing more effective dosing schedules for CPA.

Cyclophosphamide for multiple sclerosis

BACKGROUND

Multiple sclerosis is a presumed cell-mediated autoimmune disease of the central nervous system. Cyclophosphamide (CFX) is a cytotoxic and immunosuppressive agent, used in systemic autoimmune diseases. Controversial results have been reported on its efficacy in MS. We conducted a systematic review of all relevant trials, evaluating the efficacy of CFX in patients with progressive MS.

OBJECTIVES

The main objective was to determine whether CFX slows the progression of MS.

SEARCH STRATEGY

We searched the Cochrane MS Group Trials Register (searched June 2006), Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3 2006), MEDLINE (January 1966 to June 2006), EMBASE (January 1988 to June 2006) and reference lists of articles. We also contacted researchers in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating the clinical effect of CFX treatment in patients affected by clinically definite progressive MS.CFX had to be administered alone or in combination with adrenocorticotropic hormone (ACTH) or steroids. The comparison group had to be placebo or no treatment or the same co-intervention (ACTH or steroids)

DATA COLLECTION AND ANALYSIS

Two reviewers independently decided the eligibility of the study, assessed the trial quality and extracted data. We also contacted study authors for original data.

MAIN RESULTS

Of the 461 identified references, we initially selected 70: only four RCTs were included for the final analysis. Intensive immunosuppression with CFX (alone or associated with ACTH or prednisone) in patients with progressive MS compared to placebo or no treatment (152 participants) did not prevent the long-term (12, 18, 24 months) clinical disability progression as defined as evolution to a next step of Expanded Disability Status Scale (EDSS) score. However, the mean change in disability (final disability subtracted from the baseline) significantly favoured the treated group at 12 (effect size - 0.21, 95% confidence interval - 0.25 to -0.17) and 18 months (- 0.19, 95% confidence interval - 0.24 to - 0.14) but favoured the control group at 24 months (0.14, CI 0.07 to 0.21). We were unable to verify the efficacy of other schedules. Five patients died; sepsis and amenorrhea frequently occurred in treated patients (descriptive analysis).

AUTHORS' CONCLUSIONS

We were unable to achieve all of the objectives specified for the review. This review shows that the overall effect of CFX (administered as intensive schedule) in the treatment of progressive MS does not support its use in clinical practice.

High-dose therapy for autoimmune neurologic diseases

PURPOSE OF REVIEW

Autoimmune neurologic diseases are being increasingly recognized, and treated with conventional immunosuppressive agents. Patients with 'refractory' conditions have been treated with high-dose therapy, with or without autologous stem cell transplants. This paper reviews the rationale, methods, and recent results of high-dose therapy and the questions that it raises.

RECENT FINDINGS

High-dose therapy has been used in progressive multiple sclerosis and in myasthenia gravis and autoimmune neuropathies that are refractory to conventional immunotherapy. A variety of methods of immune ablation have been used; most require hematopoietic 'rescue' with stem cell transplantation. High-dose cyclophosphamide alone is immunoablative but not myeloablative, permitting the patient's endogenous stem cells to repopulate the hematopoietic/immune systems. The results have been highly encouraging in many but not all cases, with durable responses in the limited time they have been followed up. The treatments carry some risks and have been reserved for refractory cases until now.

SUMMARY

High-dose therapy, without or with stem cell transplantation, is a valuable resource for the treatment of patients with refractory autoimmune neurologic diseases. It is important to define the diseases and patient characteristics likely to lead to benefit, to optimize the methods of treatment and to establish when in the patient's course to administer it. High-dose therapy may eventually become the standard for treatment of severe progressive autoimmune neurologic disorders.

Haemopoietic stem cell transplantation in autoimmune diseases: a European perspective

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.