Interferon alpha for chronic myeloid leukemia relapsing after allogeneic bone marrow transplantation

Use of ropeginterferon in inducing graft versus myelofibrosis effect in post-transplant myelofibrosis relapse

Here, we describe a patient with post-transplant myelofibrosis with chronic graft-versus-host disease (GVHD), who showed successful molecular remission with ropeginterferon with 100% donor chimerism without any flare up of GVHD. He was initially diagnosed with polycythemia vera (PV) which progressed to myelofibrosis after 6 years. The MYSEC (Myelofibrosis Secondary to PV and ET-Prognostic Model) and MTSS (myelofibrosis transplant scoring system) scores were 13.1 and 4, respectively, and the patient was in intermediate risk group. He underwent an allogenic stem cell transplant; however, his disease gradually progressed and was administered two donor lymphocyte infusions with minimal response. A second allogeneic transplant was performed, which led to a persistent molecular remission for more than a decade, although he developed chronic skin graft-versus-host disease (GVHD). The JAK2 V617F levels started to increase 10 years post-transplant with ongoing chronic GVHD and a corresponding decrease in donor chimerism levels. He was administered ropeginterferon, which led to a decrease in JAK 2617F to undetectable levels. A graft versus myelofibrosis effect was attained with reversal to 100% donor chimerism, and he has since maintained a molecular remission with undetectable JAK 2617F levels. Chronic GVHD made him ineligible for donor lymphocyte infusions later. Thus, ropeginterferon was successful in inducing graft versus myelofibrosis effect, leading to a molecular response with no flare up of GVHD. The use of ropeginterferon needs to be further evaluated in larger cohorts of post-transplant myelofibrosis patients.

A phase 2 study of alpha interferon for molecularly measurable residual disease in chronic myeloid leukemia after allogeneic hematopoietic cell transplantation

CML therapy has improved dramatically with the development of tyrosine kinase inhibitors (TKIs). Prior to the TKI era, we conducted two trials of alpha-interferon (IFN) for post-transplant hematologic and cytogenetic relapse. The complete cytogenetic response rate was 33% and 57% respectively. This report describes a third trial in which 40 patients with molecular relapse between 6 and 12 months post-transplant were treated with IFN. The projected cytogenetic relapse at 4.5 years was 12.6% compared with 42% in the historical control group. Although this data may not apply to most patients with CML today due to the availability of multiple TKIs, the effectiveness of short term IFN in post-transplant molecular relapse is supported by long-term treatment-free-survival in 75% of patients after a median follow-up of 15.6 years. This report suggests that alpha-interferon is potentially useful in the rare patient who has post-transplant molecular relapse who does not tolerate, or is resistant to TKIs.

Is Imatinib Maintenance Required for Patients with Relapse Chronic Myeloid Leukemia Post-Transplantation Obtaining CMR? A Pilot Retrospective Investigation

Imatinib can induce complete molecular remission (CMR) in relapse chronic myelogenous leukemia (CML) after allogeneic hematopoietic stem cell transplantation, but it is indefinite whether imatinib is required to maintain CMR. We retrospectively reviewed 37 relapse CML post-transplants treated with imatinib (n = 20) or donor lymphocyte infusion (DLI) (n = 17). The rate of CMR was 85% and 76.47% (P = 0.509) and treatment-related mortality was 0% and 29.4% (P = 0.019), respectively, in imatinib and DLI groups. Fifteen patients obtaining CMR voluntarily ceased imatinib, and did not experience relapse. The 8-year overall survival (OS) after relapse was 85%±8% and 40.3±12.1% (P = 0.017), and disease-free survival (DFS) after relapse was 85%±8% and 40.3±12.1% (P = 0.011), respectively, in imatinib and DLI groups. Imatinib resulted in higher OS and DFS than that of DLI in relapse CML. Imatinib maintenance might not be required for patients with relapse CML post-transplants after they achieved full donor chimerism and CMR.

Activation and regulation of interferon-β in immune responses

Interferons (IFNs) were discovered more than half a century ago, and extensive research has since identified multifarious roles for type I IFN in human immune responses. Here, we review the functions of IFN-β in innate and adaptive immunity. We also discuss the activation and influence of IFN-β on myeloid cell types, including monocytes and dendritic cells, as well as address the effects of IFN-β on T cells and B cells. Findings from our own laboratory, which explores the molecular mechanisms of IFN-β activation by LPS and viruses, as well as from other groups investigating the regulation of IFN-β by viral proteins and endogenous factors are described. The effects of post-translational modifications of the interferon regulatory factor (IRF)-3 on IFN-β induction are also highlighted. Many unanswered questions remain concerning the regulation of the type I IFN response in inflammation, especially the role of transcription factors in the modulation of inflammatory gene expression, and these questions will form the basis for exciting avenues of future research.

Type I-IFNs control GVHD and GVL responses after transplantation

Although the effects of type II-IFN (IFN-γ) on GVHD and leukemia relapse are well studied, the effects of type I-interferon (type I-IFN, IFN-α/β) remain unclear. We investigated this using type I-IFN receptor-deficient mice and exogenous IFN-α administration in established models of GVHD and GVL. Type I-IFN signaling in host tissue prevented severe colon-targeted GVHD in CD4-dependent models of GVHD directed toward either major histocompatibility antigens or multiple minor histocompatibility antigens. This protection was the result of suppression of donor CD4+ T-cell proliferation and differentiation. Studies in chimeric recipients demonstrated this was due to type I-IFN signaling in hematopoietic tissue. Consistent with this finding, administration of IFN-α during conditioning inhibited donor CD4+ proliferation and differentiation. In contrast, CD8-dependent GVHD and GVL effects were enhanced when type I-IFN signaling was intact in the host or donor, respectively. This finding reflected the ability of type I-IFN to both sensitize host target tissue/leukemia to cell-mediated cytotoxicity and augment donor CTL function. These data confirm that type I-IFN plays an important role in defining the balance of GVHD and GVL responses and suggests that administration of the cytokine after BM transplantation could be studied prospectively in patients at high risk of relapse.

Targeted agents for chronic myelogenous leukemia: will that be the end of allogeneic bone marrow transplantation for that disease?

Although the drug imatinib has been accepted as the treatment of choice for chronic myelogenous leukemia (CML) in chronic phase (CP) throughout the Western world, allogeneic stem cell transplantation (allo-SCT) continues to remain a widely practiced first-line treatment in countries with limited health care budgets. The rationale is not scientific, but largely economically based. We analyzed a cohort of 46 CML patients who participated in a graft-versus-host disease (GVHD) prophylaxis clinical trial and underwent related HLA-matched allogeneic peripheral blood stem cell transplantation. The median time of follow-up in surviving patients was 43 months (range: 4-89 months). Risk stratification of the population was done by European Blood and Marrow Transplant (EBMT) criteria. The estimated probabilities of overall survival (OS) and leukemia-free survival (LFS) at 3 years in low EBMT risk score (0-2) patients were both 91%, respectively. We conclude that in countries with restricted access to imatinib, allo-SCT should be considered early on as front-line therapy. Continued research support for bone marrow transplantation will be needed to make a global impact on this disease.

Successful cell-mediated cytokine-activated immunotherapy for relapsed acute myeloid leukemia after hematopoietic stem cell transplantation

Acute myeloid leukemia (AML) is an extremely aggressive disease with a high relapse rate even after allogeneic hematopoietic stem cell transplantation (HSCT). We report the successful outcome of cell-mediated cytokine-activated immunotherapy in a high-risk pediatric AML patient who relapsed shortly after allogeneic HSCT. Donor lymphocyte infusion along with interferon induced a graft-versus-leukemia effect, presenting as a reversible episode of graft-versus-host disease, which led to stable complete donor chimerism and total eradication of AML for over 24 months, at the time of this report. The curative potential of immunotherapy in hematological malignancies is discussed.

Relapse of chronic myeloid leukemia after allogeneic stem cell transplantation: outcome and prognostic factors: the Chronic Myeloid Leukemia Subcommittee of the GETH (Grupo Español de Trasplante Hemopoyético)

In order to analyze the outcome of patients with chronic myeloid leukemia (CML) who relapse after allogeneic stem cell transplantation (SCT), we investigated data from 107 patients reported to the Spanish Registry, GETH. In all, 93 (87%) patients were treated after relapse; 36 out of 49 that failed to achieve a response received a second relapse-treatment, and seven a third one. At the last follow-up, the number of patients in molecular or cytogenetic remission was 29 and 13, respectively. Overall survival and progression-free survival after relapse were 53.6% (95% CI: 42.9--64.2) and 52% (95% CI: 41-63) at 5 years, respectively. In multivariate analysis, survival was significantly related to CML phase at relapse (cytogenetic or chronic phase vs advanced phases) and time from transplant to relapse (<1 vs >or=1 year). Patients with no adverse factors had a better survival compared with patients with one or two adverse features (65 vs 35 vs 0%, respectively). We conclude that a significant proportion of CML patients that relapse after transplantation can regain complete and long-lasting remissions with one or more salvage therapies. Disease stage at relapse and time from transplant to relapse should be taken into account when comparing results of different salvage treatments.

Successful treatment of JMML relapsed after unrelated allogeneic transplant with cytoreduction followed by DLI and interferon-alpha: evidence for a graft-versus-leukemia effect in non-monosomy-7 JMML

Relapse is the major cause of treatment failure after allogeneic transplantation of children with juvenile myelomonocytic leukemia (JMML), and the role of post-transplant immunomodulation is poorly understood. We report a 12-month-old child with JMML relapsed after unrelated marrow transplantation who received cytoreduction followed by donor lymphocyte infusion (DLI) with improvement, and after addition of interferon-alpha (IFN) achieved complete donor chimerism. He was weaned from IFN and has maintained complete remission for 19 months. This is the first published report of a patient with non-monosomy-7 JMML responding to post-transplant immunomodulation and suggests a role for DLI plus IFN in these patients.

Chronic myelogenous leukemia: elements of conventional chemotherapy and an overview of autografting in the treatment of the chronic phase

Chronic myelogenous leukemia (CML) consists of a clonal malignancy that arises from a pluripotent hematopoietic stem call. In most cases, neoplastic cells are characterized by the formation of a shortened chromosome 22 called the Philadelphia chromosome. It results from a reciprocal translocation between long arms of chromosomes 9 and 22. A rearranged gene (bcr-abl) is the consequence of this translocation, and it may be considered as the first step toward leukemic transformation. Conventional chemotherapy of CML in the chronic phase is unable to suppress the Ph+ leukemic clone. The treatment with the IFNalpha may induce an overall cytogenetic response rate of 40-50% of patients. Autografting for patients with CML in chronic phase may induce a 53% overall cytogenetic response rate with a duration of disease-free time and survival from the autograft ranging, respectively, from 4 to 24 mo and from 8 to 40 mo.

Adoptive immunotherapy as consolidation of remission in pediatric AML relapsing post-transplant

Treatment of acute leukemia relapse following an allogeneic transplantation is a challenge. We reinduced three pediatric patients with acute myeloid leukemia (AML) relapsing after a marrow transplantation from a sibling donor into remission with chemotherapy and used donor lymphocyte infusions (DLIs) as consolidation. In two of the cases, the allogeneic recognition was enhanced through the use of interferon in the absence of clinical graft vs. host disease (GVHD). Subsequently, all the three developed (acute grade III-IV or chronic extensive) GVHD and remain in remission with a good quality of life 19, 15 and 14 months post-relapse. We consider an active approach in the treatment of pediatric AML relapsing post-transplant justified.

Hematopoietic stem cells in chronic myeloid leukemia

Chronic myeloid leukemia (CML) is a malignant myeloproliferative disorder originating from a pluripotent hematopoietic stem cell that acquires a Philadelphia (Ph) chromosome encoding the BCR-ABL oncogenic fusion protein. This molecular abnormality that is thought to be causative in CML was the first acquired chromosome translocation associated with a human malignancy. This chromosomal translocation also makes it possible to precisely distinguish between residual normal (i.e., Ph-, BCR-ABL-) progenitor or stem cells and their leukemic counterpart, Ph+ or BCR-ABL+ progenitor/stem cells in every given sample of a patient with CML. This has provided seminal insights into the molecular and cellular biology of leukemia and also of the process of normal hematopoiesis. CML has become a fascinating model disease for malignancy in general.

Molecular monitoring of responses to DLI and DLI + IFN treatment of post-SCT relapses in patients with CML

We monitored DLI treatment of 13 post-SCT relapses using quantitative competitive (QC) RT-PCR for BCR-ABL (sensitivity 10(-5)) and compared responses to DLI alone and DLI in combination with interferon-alpha (IFN). Ten relapses (one blast crisis, five cytogenetic and four molecular) were treated with DLI+IFN, three relapses (one cytogenetic, two molecular) were treated with DLI alone. Except the patient treated in blast crisis, who died, all the patients treated with DLI+IFN achieved complete molecular remission, with the median time interval of 3.9 months (range 0.25-10.5 months). None of the three patients treated with DLI alone have achieved complete molecular remission up to now, i.e. 32, 45, and 50 months after DLI. However, in all of them some decrease of BCR-ABL transcript level was detected. Although the retrospective analyses did not confirm that IFN improved the response to DLI, our results based on sensitive molecular monitoring suggest that DLI effect, at least in some patients, is supported by IFN administration.

Imatinib mesylate therapy for relapse after allogeneic stem cell transplantation for chronic myelogenous leukemia

Twenty-eight adults with chronic myelogenous leukemia (CML) that had relapsed after allogeneic stem cell transplantation (SCT) received imatinib mesylate (400-1000 mg/d). Disease was in chronic phase in 5 patients, accelerated in 15, and blastic in 8 (7 medullary, 1 extramedullary); median time from transplantation to relapse was 9 months (range, 1-137 months). Thirteen patients had undergone salvage donor lymphocyte infusion (DLI) (median time from DLI to imatinib mesylate therapy, 4 months [range, 2-39 months]). The overall response rate was 79% (22 of 28 patients); the complete hematologic response (CHR) rate was 74% (17 of 23 patients), and the cytogenetic response rate was 58% (15 of 26 patients; complete response in 9 [35%] patients). CHR rates were 100% for chronic phase, 83% for accelerated phase, and 43% for blastic phase. The patient with extramedullary blastic disease achieved complete response. Cytogenetic response rates were 63% (12 of 19 patients) for chronic or accelerated phases (complete cytogenetic response in 8) and 43% for blastic phase (3 of 7 patients). At median follow-up of 15 months, 19 patients were alive, 9 with no evidence of disease. The 1-year estimated survival rate was 74%. Five patients had recurrence of grade 3 (3 patients) or grades 1 to 2 (2 patients) graft-versus-host disease (GVHD). Severe granulocytopenia developed in 43% of patients and thrombocytopenia in 27%; both conditions reversed with dose adjustments of imatinib mesylate. We conclude that imatinib mesylate effectively controlled CML that recurred after allogeneic SCT, but it was associated with side effects including myelosuppression and recurrence of severe GVHD.

Efficacy of thalidomide therapy for extramedullary relapse of myeloma following allogeneic transplantation

Treatment options for patients with myeloma who relapse after allogeneic stem cell transplantation are limited. Thalidomide, an antineoplastic agent, has been shown to be effective in multiple myeloma through proposed mechanisms that may include angiogenesis inhibition. Herein we report successful thalidomide treatment of four patients who relapsed following allogeneic transplantation, three of whom had predominantly extramedullary relapse. Thalidomide was well tolerated in all patients; in two patients interferon-alpha was subsequently added to thalidomide as maintenance therapy without worsening graft-versus-host disease. We suggest that extramedullary myeloma is particularly sensitive to thalidomide, speculating that growth biology may in part be dependent on angiogenesis.

Donor lymphocyte infusion followed by interferon-alpha plus low dose cyclosporine A for modulation of donor CD3 cells activity with monitoring of minimal residual disease and cellular chimerism in a patient with first hematologic relapse of chronic myelogenous leukemia after allogeneic bone marrow transplantation

A 15-year-old girl with Ph-positive chronic myelogenous leukemia in first chronic phase received bone marrow from her human leukocyte antigen matched brother. Twenty three months after bone marrow transplantation hematological relapse occured which was treated with two infusions of donor lymphocytes (DLI) (0.5x10(8) CD3/kg b.w./infusion). To enforce the graft-versus-leukemia effect (GvL), the first DLI was followed by administration of interferon-alpha (INF-alpha) 6x10(6) U/day for 30 days, whereas, after the second infusion INF-alpha was given at the same dose until hematological remission was achieved (80 doses). Minimal residual disease (MRD) was detected by conventional cytogenetics (Ph chromosome), fluorescence in situ hybridization (FISH) cytogenetics (BCR/ABL translocation) and reverse transcriptase-polymerase chain reaction (RT-PCR) Ecotropic virus integration site-1 (EVI-1 gene expression), whereas cellular chimerism was monitored by assessment of microsatellite markers PCR and Y-chromosomal DNA content FISH. When hematological remission was achieved the pancytopenia was observed and the cytogenetic and molecular investigations revealed only partial remission and mixed chimerism, however, with predominance of donor origin hematopoiesis. To diminish the myelosupressive effect of donor CD3 cells without switching-off the GvL effect, a low dose of cyclosporine A was given. Further observation revealed significant improvement of hematopoiesis with parallel gradual decline of MRD and increase of donor hematopoiesis up to complete chimerism. Graft-versus-host disease was not observed at any stage of the treatment.

Atypical chronic graft-versus-host disease following interferon therapy for chronic myeloid leukaemia relapsing after allogeneic BMT

We report a 54-year-old woman who received interferon alpha for haematological relapse of Ph-positive CML, 7 years after allogeneic BMT from an HLA-identical brother. Eighteen months after relapse, cytogenetic and molecular remission was achieved. She received interferon therapy for 25 months and it was discontinued when she developed skin lesions on her face and trunk, dysphagia and fever with respiratory failure and bilateral patchy airspace consolidation of the lung without microbiologic findings. Histologic features showed discoid lupus erythematosis, oesophagitis with pseudomembranes and a mixed pattern of lymphocytic bronchiolitis involving the alveoli and interstitial spaces all compatible with chronic GVHD. The patient was commenced on immunosuppressive therapy with complete clinical and radiological resolution. The available evidence supports an atypical presentation of chronic GVHD and suggests a role for interferon alpha in the pathogenesis of GVHD. To the best of our knowledge, this is the first case reported of severe chronic GVHD occurring during the course of interferon therapy for relapsed CML.

Chronic myelogenous leukaemia

In the last decade, improvements in both non-transplant and transplant therapy have extended the lives of patients with CML, particularly those in chronic phase. The future will probably bring a greater understanding of molecular leukaemogenesis and options for treating CML. Non-transplant therapies in development include novel agents and combination therapy. Transplant strategies seek to decrease regimen-related toxicity and directly manipulate the immune system to eradicate disease. Clinical and laboratory science seems poised to add novel therapies to the armamentarium against CML. It is exciting to contemplate what reviews of CML written 10 years from now will discuss.

Juvenile myelomonocytic leukemia relapsing after allogeneic bone marrow transplantation successfully treated with interferon-alpha

We report a 5-year-old boy with juvenile myelomonocytic leukemia (JMML) which relapsed after an allogeneic bone marrow transplant who was successfully treated with interferon-alpha (IFN-alpha). One year after starting the therapy, he remains clinically well and in complete remission while continuing treatment with IFN-alpha and bestatin. Although the precise mechanism by which remission was induced is uncertain, a GVL effect combined with a direct antileukemia effect of IFN-alpha may be responsible. Further assessment of the role of IFN-alpha in relapsed JMLL patients is warranted.