New cancer therapies. Are haematopoietic cell transplants a dead duck?

Recent therapy advances for haematological cancers including new drugs and targeted and immune therapies raise the question whether there is a future for haematopoietic cell transplants. Although encouraging, the survival improvements achieved with these new modalities in persons who might otherwise receive a transplant are modest. Furthermore, these modalities are likely to be complementary, not competitive. For example, randomised trials in multiple myeloma, the most common transplants, indicate an ongoing role for transplant despite new anti-myeloma drugs. Targeted therapies in myeloid cancers are estimated to be effective in only about 10 percent of persons with these cancers. The potential impact of current immune therapies on transplant activity is also limited because: (1) they predominately target B-cell rather than myeloid cancers; (2) many successful immune therapy recipients subsequently receive a transplant; (3) considerable data indicate much of the efficacy of allotransplants results from allogeneic rather than cancer-specific immunity not expected to operate with current immune therapies; and (4) they are at an early development stage with unknown long-term safety and efficacy. These data suggest an ongoing role for haematopoietic cell transplants in diverse haematological and genetic disorders.

Final outcomes of escalated melphalan 280 mg/m2 with amifostine cytoprotection followed autologous hematopoietic stem cell transplantation for multiple myeloma: high CR and VGPR rates do not translate into improved survival.

The most common preparative regimen for autologous transplantation (ASCT) in myeloma (MM) consists of melphalan 200 mg/m2 (MEL 200). Higher doses of melphalan 220-260 mg/m2, although relatively well tolerated, have not shown significant improvement in clinical outcomes. Several approaches have been pursued in the past to improve CR rates, including poly-chemotherapy preparative regimens, tandem ASCT, consolidation, and/or maintenance therapy. Since there is a steep dose-response effect for intravenous melphalan, we evaluated an alternative single ASCT strategy using higher-dose melphalan at 280 mg/m2 (MEL 280) with amifostine as a cytoprotectant as the maximum tolerated dose determined in an earlier phase I dose escalation trial. We report the final long-term outcomes of MM patients who underwent conditioning with MEL 280 with amifostine cytoprotection followed by ASCT. Although the complete response rate was quite high in the era pre-dating the routine use of novel therapies (proteasome inhibitors, immunomodulatory agents) (49%), the progression-free survival was a disappointing 22 months. The implications of this dichotomy between the excellent depth of ASCT response and progression-free survival are discussed.

Outpatient administration of BEAM conditioning prior to autologous stem cell transplantation for lymphoma is safe, feasible, and cost-effective.

High-dose BEAM chemotherapy (BCNU, etoposide, Ara-C, and melphalan) followed by autologous hematopoietic stem cell transplantation is frequently used as consolidative therapy for patients with recurrent or refractory Hodgkin or non-Hodgkin lymphoma. The BEAM regimen has traditionally been administered over 6 days in the hospital, with patients remaining hospitalized until hematologic recovery and clinical stability. In an effort to reduce the length of hospitalization for these patients, our institution has transitioned from inpatient (IP) to outpatient (OP) administration of BEAM conditioning. Here, we report the results of an analysis of the feasibility, cost, complications, and outcomes for the initial group of patients who received OP BEAM compared to a prior cohort of patients who received IP BEAM. Patient and disease characteristics were comparable for the two cohorts, as were engraftment kinetics. Length of hospital stay was reduced by 6 days for the OP cohort (P < 0.001), resulting in a cost savings of more than $17,000 per patient. Fewer complications occurred in the OP cohort, including severe enteritis (P = 0.01), organ toxicities (P = 0.01), and infections (P = 0.04). Overall survival rate up to 3 years posttransplant was better for the OP cohort (P = 0.02), likely due to differences in posttransplant therapies. We conclude that OP administration of BEAM conditioning is safe and may offer significant advantages, including decreased length of hospitalization, reduced costs, decreased risks for severe toxicities and infectious complications, and likely improvement in patient satisfaction and quality of life.

The Incidence and Severity of Oral Mucositis among Allogeneic Hematopoietic Stem Cell Transplantation Patients: A Systematic Review.

Oral mucositis (OM) is a debilitating early adverse effect of allogeneic hematopoietic stem cell transplantation (HSCT). The intensity of the conditioning regimen correlates with the incidence and severity of OM, but no studies have analyzed this relationship among various conditioning regimens. We performed a systematic review on the incidence and outcomes of OM in allogeneic HSCT patients and analyzed this association. A comprehensive search of several databases (Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Cochrane CRCT, Cochrane DSR, Scopus) from 1990 to 2014 for studies of OM in allogeneic HSCT patients was conducted. Professional societies' meeting abstracts were also searched. Grade of OM was analyzed based on the World Health Organization (WHO) or National Cancer Institutes (NCI) Common Terminology Criteria for Adverse Events scales. Severe mucositis was defined as either grades 2 to 4 or grades 3 and 4, depending on the studies' definition of severity. Cohorts were analyzed based on regimen intensity; ie, reduced-intensity conditioning (RIC) (including nonmyeloablative) and myeloablative (MA). Random effect (RE) and standard logistic models weighted by the number of patients in each cohort were used for comparisons. A total of 624 studies were generated from the search. Of the 395 patients in 8 eligible MA regimen studies, 73.2% experienced any OM, whereas in 245 patients in the 6 eligible RIC regimen studies, 86.5% experienced any OM (chi-square P < .0001; RE, P = .05). Severe (grades 2 to 4) OM occurred among 79.7% of the WHO/NCI-graded MA patients and 71.5% of RIC patients (chi-square, P = .0421; RE, P < .01). In comparing graft-versus-host disease (GVHD) prophylaxis, only 55.4% of patients receiving nonmethotrexate regimens experienced OM; this was lower (chi-square, P < .0001; RE, P = .06) than that found among patients who received methotrexate (83.4%), either standard or reduced dose. Besides NCI and WHO grading scales, other scales included in the studies were Oral Mucositis Index, the Southwest Oncology Group Criteria, and Eastern Cooperative Oncology Group scale. To our knowledge, this is the first analysis on OM in allogeneic HSCT patients with respect to conditioning regimens, and we observed that RIC regimens led to a high incidence of OM similar to that of MA regimens. Clinical trials on treatment of OM are lacking, emphasizing the essential need for prospective studies in this arena. A significant variance in the criteria for grading OM underscores the importance of establishing a standard grading system for OM measurement in future allogeneic HSCT clinical trials.

A phase I study using bortezomib with weekly idarubicin for treatment of elderly patients with acute myeloid leukemia.

We report the results of a phase I study with four dose levels of bortezomib in combination with idarubicin. Eligible patients were newly diagnosed with acute myeloid leukemia (AML) age ≥60 years, or any adult with relapsed AML. Bortezomib was given twice weekly at 0.8, 1.0, or 1.2 mg/m(2) with once weekly idarubicin 10 mg/m(2) for four weeks. Twenty patients were treated: 13 newly diagnosed (median age 68, range 61-83) and 7 relapsed (median age 58, range 40-77). Prior myelodysplastic syndrome (MDS) was documented in 10/13 (77%) newly diagnosed and 1/7 (14%) relapsed patients; the three newly diagnosed patients without prior MDS had dyspoietic morphology. Two dose-limiting toxicities occurred at the initial dose level (bortezomib 0.8 mg/m(2) and idarubicin 10 mg/m(2)); idarubicin was reduced to 8 mg/m(2) without observing subsequent dose-limiting toxicities. The maximum tolerated dose in this study was bortezomib 1.2 mg/m(2) and idarubicin 8 mg/m(2). Common adverse events included: neutropenic fever, infections, constitutional symptoms, and gastrointestinal symptoms. No subjects experienced neurotoxicity. Most patients demonstrated hematologic response as evidenced by decreased circulating blasts. Four patients (20%) achieved complete remission. There was one treatment-related death. The combination of bortezomib and idarubicin in this mostly poor-risk, older AML group was well tolerated and did not result in high mortality. This trial was registered at www.clinicaltrials.gov as #NCT00382954.

A phase I study of decitabine and rapamycin in relapsed/refractory AML.

A phase I study utilizing decitabine (DAC) followed by the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, in patients with relapsed/refractory adult AML was undertaken to assess safety and feasibility. Patients received DAC 20mg/m(2) intravenously daily for 5 days followed by rapamycin from day 6 to day 25 at doses of 2 mg, 4 mg, and 6 mg/day in a standard 3+3 dose escalation design. Twelve patients completed treatment for safety evaluation. Maximum tolerated dose (MTD) was not reached, and except for grade 3 mucositis in 4 patients, no other significant unexpected non-hematologic toxicities have occurred indicating safety of this regimen. This trial is registered at clinical trials.gov as NCT00861874.

A phase 1 trial of eltrombopag in patients undergoing stem cell transplantation after total body irradiation.

Stem cell transplantation can be associated with significant periods of thrombocytopenia, necessitating platelet transfusions and contributing to the risk of bleeding. Thrombopoietin receptor agonists have been shown to enhance platelet counts in other clinical settings, and so a phase 1 clinical trial was conducted to assess the safety, pharmacokinetics, and maximum tolerated dose of once-daily eltrombopag in patients undergoing stem cell transplantation with conditioning regimens containing total body irradiation ≥400 cGy. Eltrombopag was examined at dosage levels of 75, 150, 225, and 300 mg given orally once daily for 27 days, starting at 24 to 48 hours post-transplantation. Pharmacokinetic sampling was performed over a 24-hour period after the first dose of eltrombopag, as well as during the second week of treatment (steady-state). Nineteen patients were enrolled, 15 of whom completed protocol treatments. Three patients completed each dose level up to 225 mg, and 6 completed treatment at the highest dose of 300 mg. Four patients were replaced because drug compliance was <75% of planned doses. No dose-limiting toxicities were observed in this heterogeneous post-transplantation patient population. Common adverse events were related to standard stem cell transplantation. One episode of pulmonary embolus occurred 9 days after discontinuation of eltrombopag, and the only other thromboembolic episode was a grade 2 catheter-related clot. We conclude that up to 27 days of once-daily dosing of eltrombopag after stem cell transplantation is well tolerated.

Autologous haematopoietic cell transplantation for non-Hodgkin lymphoma with secondary CNS involvement.

Pre-existing central nervous system (CNS) involvement may influence referral for autologous haematopoietic cell transplantation (AHCT) for patients with non-Hodgkin lymphoma (NHL). The outcomes of 151 adult patients with NHL with prior secondary CNS involvement (CNS(+) ) receiving an AHCT were compared to 4688 patients without prior CNS lymphoma (CNS(-) ). There were significant baseline differences between the cohorts. CNS(+) patients were more likely to be younger, have lower performance scores, higher age-adjusted international prognostic index scores, more advanced disease stage at diagnosis, more aggressive histology, more sites of extranodal disease, and a shorter interval between diagnosis and AHCT. However, no statistically significant differences were identified between the two groups by analysis of progression-free survival (PFS) and overall survival (OS) at 5 years. A matched pair comparison of the CNS(+) group with a subset of CNS(-) patients matched on propensity score also showed no differences in outcomes. Patients with active CNS lymphoma at the time of AHCT (n = 55) had a higher relapse rate and diminished PFS and OS compared with patients whose CNS lymphoma was in remission (n = 96) at the time of AHCT. CNS(+) patients can achieve excellent long-term outcomes with AHCT. Active CNS lymphoma at transplant confers a worse prognosis.

The hematopoietic cell transplantation specific comorbidity index and survival after extracorporeal photopheresis, pentostatin, and reduced dose total body irradiation conditioning prior to allogeneic stem cell transplantation.

Hematopoietic-cell-transplantation-specific-comorbidity-index (HCT-CI) has been reported as a predictor of survival in allogeneic-transplant recipients; however its validity has recently been challenged. We evaluated the association of HCT-CI with survival of transplant recipients who underwent reduced-intensity-conditioning (RIC) with photopheresis, pentostatin, and total-body-irradiation. Median age of 103 patients selected was 55 years. Most patients (58.3%) had high (≥ 3) HCT-CI. Median OS was 298 days. Age, disease-type, disease-status, HCT-CI correlated with survival on bivariate analysis. On multivariate analysis, only HCT-CI was significantly associated with OS (low HCT-CI HR=0.29, CI 0.091-0.886; intermediate HCT-CI HR=0.41, CI 0.226-0.752). Our findings suggest HCT-CI as an independent predictor of survival in the setting of RIC transplants.

Allogeneic hematopoietic stem cell transplantation (HSCT) for high-risk acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS): how can we improve outcomes in the near future?

Substantive advances in the past decade or so have allowed for a wider spectrum of patients to undergo allo-HSCT and have increased its safety, thus broadening the application of this therapy[36]. That said, disease persistence or (more commonly) recurrence remains as primary problems. A combination of "extrinsic" and "intrinsic" methods is now available and ready for additional clinical testing and/or utilization. Fortunately, one can be somewhat optimistic that better results will be achieved, perhaps very soon. However, and as these strategies and techniques are evaluated, it should be realized that some may be too complex and/or expensive for widespread use as the need to reduce costs becomes more pressing.

Use of eltrombopag, a thrombopoietin receptor agonist, in post-transplantation thrombocytopenia.

Persistent thrombocytopenia after stem cell transplantation can lead to increased morbidity and mortality [1,2]. The underlying causes are often multifactorial in this patient population [3,4]. In autologous transplantation, thrombocytopenia is usually a result of poor engraftment or a sign of impending disease relapse. In allogeneic stem cell transplantation, the etiology is often more complex with engraftment deficits, medication effects, graft versus host disease (GVHD), and other immunologic processes potentially contributing. Eltrombopag is an orally available nonpeptide thrombopoietin (TPO) receptor agonist which interacts with the transmembrane domain of the receptor on bone marrow megakaryocytes and upstream progenitor/stem cells. It has been studied in patients with chronic idiopathic thrombocytopenic purpura [5] and in patients with thrombocytopenia secondary to hepatitis C infection [6]. Unlike the case with recombinant human TPO, its use has not been associated with anti-platelet antibody production [7]. We report two cases of post-transplantation thrombocytopenia, one allogeneic and one autologous, where eltrombopag was given to treat prolonged thrombocytopenia. The use of eltrombopag in these two cases was effective in elevating platelet counts to levels that eliminated the need for platelet transfusions.

Involved field radiation therapy following high dose chemotherapy and autologous stem cell transplant benefits local control and survival in refractory or recurrent Hodgkin lymphoma.

BACKGROUND AND PURPOSE: Patients with recurrent or primary refractory Hodgkin lymphoma (HL) treated with high dose chemotherapy (HDT) and autologous stem cell transplant (ASCT) commonly relapse post-ASCT in previous disease sites. We sought to evaluate involved field radiation therapy (IFRT) following ASCT and patterns of recurrence, overall survival (OS), and disease specific survival (DSS). METHODS AND MATERIALS: Between May 1993 and October 2003, 62 (n=66) evaluable patients with refractory/relapsed HL underwent HDT followed by ASCT. Thirty-two (52%) patients received IFRT following transplant. Survival was calculated from the day of hematopoietic stem cell infusion. RESULTS: Median follow-up was 2.3 years (range 0.03-11.56). Estimated 3-year OS (p=0.05) and DSS (p=0.08) were 69.6% and 82.1% with IFRT and 40% and 57.6% without IFRT on univariate analysis. B-symptoms were adverse on univariate (p=0.007) and multivariate (p=0.01) analysis. HL patients who received IFRT following ASCT had improved local control in areas of previously recurrent disease (p=0.03). CONCLUSION: OS and DSS showed marginal benefit at 3 years. Given the retrospective nature of our study and attendant selection bias that can be both positive and negative, a future prospective study is warranted to better understand the value of IFRT in the transplant setting.

A Phase I trial: dose escalation of melphalan in the "BEAM" regimen using amifostine cytoprotection.

With the eventual goal of reducing relapse and thus improving overall survival in selected lymphoma patients, a Phase I study was performed using the cytoprotectant amifostine to permit safe dose-augmentation of melphalan in the carmustine (BCNU), etoposide, cytarabine (arabinosylcytosine), and melphalan (BEAM) regimen before autologous hematopoietic stem cell transplantation. Between 30 July 2003 and 25 November 2008, a total of 32 lymphoma patients were entered, of which 28 were evaluable. We found the melphalan dose in BEAM could be safely escalated to at least 260 mg/m², a substantial increase from the usual dose of 140 mg/m² in BEAM while the trial was terminated early due to poor accrual, no maximal tolerated dose or dose-limiting toxicity was found. A Phase II trial is planned.

Platelet transfusions: trigger, dose, benefits, and risks.

Over the last half century, platelet transfusion has been an effective therapy for the prevention and treatment of bleeding, particularly in patients with hematologic malignancies. Recent randomized trials have demonstrated that current practices may be suboptimal in a number of ways. The rationale for parsimony in the use of this powerful therapy includes previously described severe and fatal adverse outcomes (including refractoriness, hemolysis from ABO-mismatched transfusions, acute lung injury, and bacterial sepsis), newly described serious potential risks (including thrombosis and earlier leukemic recurrence), difficulty in maintaining adequate supplies of platelets, the need to place volunteer donors on cell separators to provide the product, and cost. Recent findings demonstrate that the platelet count threshold for prophylactic transfusion can be as low as 10,000/µL, and a therapeutic rather than a prophylactic strategy of transfusion for bleeding manifestations only may be equally safe for most patients. Another recently completed study suggests that very low doses of platelet transfusions (the equivalent of half a unit of apheresis platelets or two to three units of whole blood-derived platelets) are as effective at preventing bleeding as much higher doses. One question for which there are no randomized trial data is at what threshold prophylactic platelet transfusion should be given before invasive procedures or major surgery. The typically recommended threshold of 50,000/µL is based only on expert opinion, and substantial observational data indicate that this threshold leads to many transfusions that are likely unnecessary and therefore represent risk with little or no additional benefit.

Allogeneic transplantation for therapy-related myelodysplastic syndrome and acute myeloid leukemia.

Therapy-related myelodysplastic syndromes (t-MDSs) and acute myeloid leukemia (t-AML) have a poor prognosis with conventional therapy. Encouraging results are reported after allogeneic transplantation. We analyzed outcomes in 868 persons with t-AML (n = 545) or t-MDS (n = 323) receiving allogeneic transplants from 1990 to 2004. A myeloablative regimen was used for conditioning in 77%. Treatment-related mortality (TRM) and relapse were 41% (95% confidence interval [CI], 38-44) and 27% (24-30) at 1 year and 48% (44-51) and 31% (28-34) at 5 years, respectively. Disease-free (DFS) and overall survival (OS) were 32% (95% CI, 29-36) and 37% (34-41) at 1 year and 21% (18-24) and 22% (19-26) at 5 years, respectively. In multivariate analysis, 4 risk factors had adverse impacts on DFS and OS: (1) age older than 35 years; (2) poor-risk cytogenetics; (3) t-AML not in remission or advanced t-MDS; and (4) donor other than an HLA-identical sibling or a partially or well-matched unrelated donor. Five-year survival for subjects with none, 1, 2, 3, or 4 of these risk factors was 50% (95% CI, 38-61), 26% (20-31), 21% (16-26), 10% (5-15), and 4% (0-16), respectively (P < .001). These data permit a more precise prediction of outcome and identify subjects most likely to benefit from allogeneic transplantation.