Prospective Study of a Novel, Radiation-Free, Reduced-Intensity Bone Marrow Transplantation Platform for Primary Immunodeficiency Diseases.

Allogeneic blood or marrow transplantation (BMT) is a potentially curative therapy for patients with primary immunodeficiency (PID). Safe and effective reduced-intensity conditioning (RIC) approaches that are associated with low toxicity, use alternative donors, and afford good immune reconstitution are needed to advance the field. Twenty PID patients, ranging in age from 4 to 58 years, were treated on a prospective clinical trial of a novel, radiation-free and serotherapy-free RIC, T-cell-replete BMT approach using pentostatin, low-dose cyclophosphamide, and busulfan for conditioning with post-transplantation cyclophosphamide-based graft-versus-host-disease (GVHD) prophylaxis. This was a high-risk cohort with a median hematopoietic cell transplantation comorbidity index of 3. With median follow-up of survivors of 1.9 years, 1-year overall survival was 90% and grade III to IV acute GVHD-free, graft-failure-free survival was 80% at day +180. Graft failure incidence was 10%. Split chimerism was frequently observed at early post-BMT timepoints, with a lower percentage of donor T cells, which gradually increased by day +60. The cumulative incidences of grade II to IV and grade III to IV acute GVHD (aGVHD) were 15% and 5%, respectively. All aGVHD was steroid responsive. No patients developed chronic GVHD. Few significant organ toxicities were observed. Evidence of phenotype reversal was observed for all engrafted patients, even those with significantly mixed chimerism (n = 2) or with unknown underlying genetic defect (n = 3). All 6 patients with pre-BMT malignancies or lymphoproliferative disorders remain in remission. Most patients have discontinued immunoglobulin replacement. All survivors are off immunosuppression for GVHD prophylaxis or treatment. This novel RIC BMT approach for patients with PID has yielded promising results, even for high-risk patients.

Pentostatin, Cyclophosphamide, and Rituximab Followed by Alemtuzumab for Relapsed or Refractory Chronic Lymphocytic Leukemia: A Phase 2 Trial of the ECOG-Acrin Cancer Research Group (E2903).

Patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL) may benefit from salvage chemoimmunotherapy (CIT). To explore further the use of CIT in the pre-novel agent era, ECOG-ACRIN undertook a phase 2 trial (E2903) for R/R CLL utilizing pentostatin, cyclophosphamide, and rituximab (PCR) followed by a consolidation course of alemtuzumab. This trial enrolled 102 patients with a median age of 64 years. Treatment consisted of 6 cycles of PCR followed by alemtuzumab for either 4 or 18 weeks depending on the initial response to PCR. The overall response after PCR (complete remission, CR, nodular partial remission, nPR, and partial remission, PR) was 55%. Major responses (CR or nPR) were achieved in 6%. The median overall survival (OS) and the median progression-free survival were 28 and 12 months, respectively. The most serious nonlethal adverse events were myelosuppression, febrile neutropenia, fatigue, nausea, and hyponatremia. PCR is an effective and well-tolerated nucleoside-based regimen for heavily pretreated CLL patients with R/R disease. The addition of alemtuzumab to CLL patients with a minor response (PR) or stable disease did not result in a significant number of higher responses (CR or nPR) nor an improvement in OS.

The successful use of radiofrequency-induced heat therapy for cutaneous leishmaniasis: a review.

The present gold standard of the treatment of cutaneous leishmaniasis (CL) is pentavalent antimonials either sodium stibogluconate (Pentostam) or meglumine antimoniate (Glucantime), These drugs are quite toxic. They are given by injection and usually administered intramuscularly or intravenously for three weeks or intralesionally for seven or more weeks. That is why the successful introduction of radiofrequency-induced heat therapy using a Thermomed™ 1.8 instrument administered in a single application, with minimal toxic effects, is so important for the treatment of CL.

Synchronous gastric and ampullary adenocarcinomas in a hairy cell leukemia patient treated with pentostatin eight years prior.

Hairy cell leukemia patients are at increased risk for second malignancies, including both solid and lymphoid neoplasms. Along with other factors, multiple immune defects present in hairy cell leukemia likely contribute to subsequent carcinogenesis. We report herein a case of synchronous high-grade gastric and ampullary adenocarcinomas in a patient with a history of hairy cell leukemia treated eight years prior with pentostatin. We include a review of immune alterations induced by both hairy cell leukemia and its therapies, and link them with the occurrence of second cancers in these patients.

Renal complications in chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis: the Mayo Clinic experience.

While the renal complications of plasma cell dyscrasia have been well-described, most information in patients with chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis is derived from case reports. This is a retrospective analysis of patients with chronic lymphocytic leukemia or monoclonal B-cell lymphocytosis who underwent kidney biopsy for renal insufficiency and/or nephrotic syndrome. Between January 1995 and June 2014, 49 of 4,024 (1.2%) patients with chronic lymphocytic leukemia (n=44) or monoclonal B-cell lymphocytosis (n=5) had a renal biopsy: 34 (69%) for renal insufficiency and 15 (31%) for nephrotic syndrome. The most common findings on biopsy were: membranoproliferative glomerulonephritis (n=10, 20%), chronic lymphocytic leukemia interstitial infiltration as primary etiology (n=6, 12%), thrombotic microangiopathy (n=6, 12%), and minimal change disease (n=5, 10%). All five membranoproliferative glomerulonephritis patients treated with rituximab, cyclophosphamide and prednisone-based regimens had recovery of renal function compared to 0/3 patients treated with rituximab with or without steroids. Chronic lymphocytic leukemia infiltration as the primary cause of renal abnormalities was typically observed in relapsed/refractory patients (4/6). Thrombotic microangiopathy primarily occurred as a treatment-related toxicity of pentostatin (4/6 cases), and resolved with drug discontinuation. All cases of minimal change disease resolved with immunosuppressive agents only. Renal biopsy plays an important role in the management of patients with chronic lymphocytic leukemia or monoclonal B-cell lymphocytosis who develop renal failure and/or nephrotic syndrome.

Drug-induced thrombotic microangiopathy: Experience of the Oklahoma Registry and the BloodCenter of Wisconsin.

Many drugs have been reported to cause thrombotic microangiopathy (TMA), often described as thrombotic thrombocytopenic purpura (TTP) or hemolytic-uremic syndrome (HUS). We recently established criteria to evaluate the evidence for a causal association of a drug with TMA and then we systematically reviewed all published reports of drug-induced TMA (DITMA) to determine the level of evidence supporting a causal association of the suspected drug with TMA. On the basis of this experience, we used these evaluation criteria to assess the Oklahoma TTP-HUS Registry patients who had been previously categorized as drug-induced, 1989-2014. We also reviewed the experience of the BloodCenter of Wisconsin with testing for drug-dependent antibodies reactive with platelets and neutrophils in patients with suspected immune-mediated DITMA, 1988-2014. Among 58 patients in the Oklahoma Registry previously categorized as drug-induced (15 suspected drugs), 21 patients (three drugs: gemcitabine, pentostatin, quinine) had evidence supporting a definite association with TMA; 19 (90%) of the 21 patients had quinine-induced TMA. The BloodCenter of Wisconsin tested 40 patients with suspected DITMA (eight drugs); drug-dependent antibodies, supporting a definite association with TMA, were identified in 30 patients (three drugs: oxaliplatin, quinine, vancomycin); 28 (93%) of the 30 patients had quinine-induced TMA. Combining the data from these two sources, 51 patients (five drugs) have been identified with evidence supporting a definite association with TMA. DITMA was attributed to quinine in 47 (92%) of these 51 patients.

Chemoimmunotherapy for relapsed/refractory and progressive 17p13-deleted chronic lymphocytic leukemia (CLL) combining pentostatin, alemtuzumab, and low-dose rituximab is effective and tolerable and limits loss of CD20 expression by circulating CLL cells.

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) patients with purine analog refractory disease or TP53 dysfunction still have limited treatment options and poor survival. Alemtuzumab-containing chemoimmunotherapy regimens can be effective but frequently cause serious infections. We report a Phase II trial testing the efficacy and tolerability of a short-duration regimen combining pentostatin, alemtuzumab, and low-dose high-frequency rituximab designed to decrease the risk of treatment-associated infections and to limit the loss of CD20 expression by CLL cells. The study enrolled 39 patients with progressive CLL that was either relapsed/refractory (n = 36) or previously untreated with 17p13 deletion (17p13-) (n = 3). Thirteen (33%) patients had both 17p13- and TP53 mutations predicted to be dysfunctional, and eight patients had purine analog refractory CLL without TP53 dysfunction. Twenty-six (67%) patients completed therapy, with only five (13%) patients having treatment-limiting toxicity and no treatment-related deaths. Twenty-two (56%) patients responded to treatment, with 11 (28%) complete responses (four with incomplete bone marrow recovery). Median progression-free survival was 7.2 months, time to next treatment was 9.1 months, and overall survival was 34.1 months. The majority of deaths (82%) were caused by progressive disease, including transformed diffuse large B-cell lymphoma (n = 6). Correlative studies showed that low-dose rituximab activates complement and natural killer cells without a profound and sustained decrease in expression of CD20 by circulating CLL cells. We conclude that pentostatin, alemtuzumab, and low-dose high-frequency rituximab is a tolerable and effective therapy for CLL and that low-dose rituximab therapy can activate innate immune cytotoxic mechanisms without substantially decreasing CD20 expression.

Ofatumumab-based chemoimmunotherapy is effective and well tolerated in patients with previously untreated chronic lymphocytic leukemia (CLL).

BACKGROUND: Although rituximab-based chemoimmunotherapy (CIT) has substantially improved clinical outcomes in chronic lymphocytic leukemia (CLL), only 40% to 50% of patients achieve a complete remission (CR). There remains interest in identifying new approaches to improve the effectiveness of CIT. Ofatumumab is a fully human anti-CD20 monoclonal antibody with greater apparent single-agent activity than rituximab in CLL patients. METHODS: Previously untreated CLL patients in need of therapy received 6 cycles of CIT induction with pentostatin, cyclophosphamide, and ofatumumab (PCO) followed by response assessment. RESULTS: Of the 48 patients enrolled, 77% completed PCO induction. Adverse events during induction included grade 3+ hematologic toxicity (27%) and grade 3+ nonhematologic toxicity (23%). Median CD4 count after induction and 6 months later were 186 × 10(6)/L and 272 × 10(6) /L. The overall response rate was 96% (46 of 48 patients), and the CR rate was 46% (22 of 48 patients). Among the 38 patients who underwent minimal residual disease evaluation, 7 (18%) were negative for minimal residual disease. After median follow-up of 24 months, 10 (21%) patients have progressed and 8 (17%) have required retreatment. The efficacy and toxicity of ofatumumab-based CIT compare favorably to our historical trials of rituximab-based CIT using an identical chemotherapy backbone (n = 64). Time to retreatment also appeared longer for ofatumumab-based CIT (free of retreatment at 24 months: 86% [95% confidence interval = 75-99] versus 68% [95% confidence interval = 56-81] for rituximab-based CIT). CONCLUSIONS: Ofatumumab-based CIT is well tolerated in patients with previously untreated CLL. The efficacy of ofatumumab-based CIT compares favorably to historical trials of rituximab-based CIT, suggesting randomized trials comparing ofatumumab-based CIT and rituximab-based CIT should be considered.

A Phase III trial of fludarabine, cyclophosphamide, and rituximab vs. pentostatin, cyclophosphamide, and rituximab in B-cell chronic lymphocytic leukemia.

BACKGROUND: Uncontrolled studies comparing pentostatin (P), cyclophosphamide (C), and rituximab (R) (PCR) to fludarabine plus C+R (FCR) suggest similar efficacy with fewer infectious complications with PCR. We compared FCR and PCR in previously-untreated or minimally-treated B-cell chronic lymphocytic leukemia (CLL). TREATMENT: FCR (F 20 mg/m(2) Days 1-5, C 600 mg/m(2) Day 1, R 375 mg/m(2) Day 1) (28-day cycles) or PCR (P 4 mg/m(2) Day 1, C 600 mg/m(2) Day 1, R 375 mg/m(2) Day 1) (21-day cycles). Dose 1 of R: 100 mg/m(2) was given on Day 8 Cycle 1 and the remainder on Day 9; in subsequent cycles the entire dose was given on Day 1. RESULTS: Ninety-two patients were randomly assigned to each group (N = 184). Groups were balanced; ~20% had received prior chemotherapy. The infection rate (FCR/PCR) was 31%/36%, the infective event rate was 38%/45%; 30 (35%)/37 (44%) patients were hospitalized; total hospitalization days was 271/404. 12 (14%)/6 (7%) patients achieved complete remissions (CR); the overall response rate (ORR) including CR+nodular PR (nPR)+PR was 59%/49%. Grade 3-4 treatment related AEs: neutropenia (69%/57%), leukopenia (34%/17%), thrombocytopenia (13%/6%). Grade 3-4 infections: febrile neutropenia (8%/6%), fever (2%/6%), infection (1%/3%), urinary tract infection (1%/0%), pneumonia (3%/1%), and sepsis (1%/2%); 5 deaths (1 FCR/4 PCR) were treatment-related. CONCLUSIONS: PCR and FCR have significant activity in CLL and can be given safely in the community setting despite significant toxicity. ORRs were lower than expected; the CR rate was higher (NS) with FCR. This trial did not demonstrate a lower infection rate with PCR.

Posterior reversible encephalopathy syndrome associated with deoxycoformycin and alemtuzumab.

Posterior reversible encephalopathy syndrome (PRES) is a combined clinical and radiological syndrome characterised by headaches, encephalopathy, seizures and visual loss. We present the case of a 55-year-old male who developed this condition following treatment with deoxycoformycin and alemtuzumab. We review the literature considering diagnosis, pathophysiology and optimal strategies for treatment of this condition.

Pentostatin plus cyclophosphamide safely and effectively prevents immunotoxin immunogenicity in murine hosts.

PURPOSE: The success of immunotoxin therapy of cancer is limited by host production of neutralizing antibodies, which are directed toward the Pseudomonas exotoxin A (PE) component. In this proof-of-principle study using a well-established murine model, we hypothesized that a newly developed immune depletion regimen consisting of pentostatin plus cyclophosphamide would abrogate anti-immunotoxin reactivity. EXPERIMENTAL DESIGN: BALB/c hosts were injected weekly with recombinant immunotoxin (RIT) SS1P, which is an antimesothelin Fv antibody fragment genetically fused to a 38 kDa portion of PE, and has been evaluated in clinical trials. Experimental cohorts received induction chemotherapy consisting of pentostatin (P) plus cyclophosphamide (C) prior to initial RIT exposure; some cohorts received further maintenance PC therapy of varying intensity just prior to each weekly RIT challenge. Cohorts were monitored for T, B, myeloid cell depletion, and for total anti-SS1P antibody (Ab) formation. RESULTS: Controls uniformly developed anti-SS1P Ab after the third RIT exposure. Induction PC therapy reduced the frequency of hosts with anti-SS1P Ab. Abrogation of antibody generation was improved by maintenance PC therapy: nearly 100% of recipients of intensive PC maintenance were free of anti-SS1P Ab after 9 weekly RIT doses. The most effective PC regimen yielded the greatest degree of host B-cell depletion, moderate T-cell depletion, and minimal myeloid cell depletion. CONCLUSIONS: Induction and maintenance PC chemotherapy safely prevented anti-immunotoxin antibody formation with uniform efficacy. These data suggest that immunotoxin therapy might be used in combination with pentostatin plus cyclophosphamide chemotherapy to improve the targeted therapy of cancer.

Prophylaxis of graft-versus-host disease in unrelated donor transplantation with pentostatin, tacrolimus, and mini-methotrexate: a phase I/II controlled, adaptively randomized study.

PURPOSE: Acute graft-versus-host disease (aGVHD) is a major cause of morbidity and mortality after matched unrelated, related, or mismatched related donor hematopoietic stem-cell transplantation (HSCT). Improved GVHD prevention methods are needed. Pentostatin, an adenosine deaminase inhibitor, leads to lymphocyte depletion with low risk of myelosuppression. We hypothesized that addition of pentostatin to GVHD prophylaxis with tacrolimus and mini-methotrexate may improve outcomes, and we conducted a Bayesian adaptively randomized, controlled, dose-finding study, taking into account toxicity and efficacy. PATIENTS AND METHODS: Success was defined as the patient being alive, engrafted, in remission, without GVHD 100 days post-HSCT and no grade ≥ 3 GVHD at any time. Patients were randomly assigned to pentostatin doses of 0, 0.5, 1.0, 1.5, and 2.0 mg/m(2) with drug administered on HSCT days 8, 15, 22, and 30. Eligible patients were recipients of mismatched related (n = 10) or unrelated (n = 137) donor HSCT. RESULTS: Median age was 47 years. Thirty-seven, 10, 29, 61, and 10 patients were assigned to the control and four treatment groups, respectively, with comparable baseline characteristics. Pentostatin doses of 1.0 and 1.5 mg/m(2) had the highest success rates (69.0% and 70.5%) versus control (54.1%). The posterior probabilities that the success rates were greater with 1.5 mg/m(2) or 1.0 mg/m(2) versus control are 0.944 and 0.821, respectively. Hepatic aGVHD rates were 0%, 17.2%, and 11.1%, respectively, for 1.5 mg/m(2), 1.0 mg/m(2), and control groups. No grades 3 to 4 aGVHD occurred in 11 HLA-mismatched recipients in the 1.5 mg/m(2) group. CONCLUSION: Pentostatin increased the likelihood of success as defined here, and should be further investigated in larger randomized, confirmatory studies.

Phase II study of alemtuzumab in combination with pentostatin in patients with T-cell neoplasms.

PURPOSE: To examine the efficacy and safety of the combination of alemtuzumab and pentostatin in patients with T-cell neoplasms. PATIENTS AND METHODS: We treated 24 patients with a variety of T-cell leukemias and lymphomas with a combination of alemtuzumab 30 mg intravenously (IV) three times weekly for up to 3 months and pentostatin 4 mg/m(2) IV weekly for 4 weeks followed by alternate weekly administration for up to 6 months. Prophylactic antibiotics including antiviral, antifungal, and antibacterial agents were administered during the treatment and for 2 months after its completion. RESULTS: The median age of patients was 57 years (range, 21 to 79 years). Eight patients were previously untreated, and 16 had a median of two prior therapies (range, one to six regimens). Thirteen patients responded to treatment (11 complete responses [CRs] and two partial responses), for an overall response rate of 54%. The median response duration was 19.5 months. Monoclonal T-cell receptor chain gene rearrangements were detected by polymerase chain reaction in bone marrow of 20 of 22 evaluable patients and became negative in five of seven evaluable patients in CR. Opportunistic infections caused by pathogens associated with severe T-cell dysfunction were common. CONCLUSION: The combination of alemtuzumab and pentostatin is feasible and effective in T-cell neoplasms. Although infections, including cytomegalovirus reactivation, are a concern, they may be minimized with adequate prophylactic antibiotic therapy.

Pentostatin treatment combinations in chronic lymphocytic leukemia.

There have been great strides in the treatment of chronic lymphocytic leukemia (CLL). Fludarabine is the most widely studied of the purine analogs that have significantly impacted the treatment of this disease. Pentostatin has also been shown to have clinical activity in CLL and appears to be less toxic than its fludarabine counterpart, which may offer some important advantages. This text will review the rationale and more recent clinical trial results for pentostatin-based combinations in both the upfront and relapsed treatment setting for patients with CLL. Attention to the frequency of response, ability to achieve minimal residual disease, and toxicity from these approaches will be emphasized. Where feasible, we will also compare the impact of pentostatin-based treatments to fludarabine-based combinations in CLL. In addition, this review will update the latest relevant work presented at the recent 2008 American Society of Hematology meeting and future directions in regard to the continued study of pentostatin-based combinations will be discussed.

Pentostatin in chronic lymphocytic leukemia.

BACKGROUND: Chronic lymphocytic leukemia (CLL) is a disease that typically afflicts older individuals with a median age of diagnosis in the eighth decade of life for which treatments available now are not curative. Although purine analogue based combinations produce complete responses (CRs) in many patients, the use of these combinations has been limited by toxicity including myelosuppression and an increased risk of infectious complications. OBJECTIVE: To identify the role of pentostatin, a specific inhibitor of adenosine deaminase (ADA), in the treatment of CLL. We compare pentostatin to other purine analogues, most notably fludarabine, with regard to safety and efficacy. Finally, we review the use of pentostatin in other diseases. METHODS: The scope of this review encompasses the history of treatment for CLL as well as the genesis of modern combination chemoimmunotherapy and the advantages of pentostatin within such a treatment program. RESULTS: Combination therapy with pentostatin seems to provide response frequencies comparable to fludarabine based combinations but with less toxicity and with greater ease of administration.

Community-based phase II trial of pentostatin, cyclophosphamide, and rituximab (PCR) biochemotherapy in chronic lymphocytic leukemia and small lymphocytic lymphoma.

We conducted a multicenter, community-based phase II trial of PCR biochemotherapy (pentostatin 4 mg/m2, cyclophosphamide 600 mg/m2, and rituximab 375 mg/m2) every 3 weeks for up to 6 cycles in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). The study was stopped after enrolling 24 patients because of diminished investigator interest after 8 patients discontinued treatment because of adverse events, and 5 others died during treatment. The median age of patients was 69 years; 11 patients were over age 70, and 71% had Rai stage III or IV disease. The response rate among the 17 evaluable patients who completed 3 cycles of therapy was 58% (35%-81%, 95% confidence interval), with 2 complete responders (both greater than 70 years of age) and 7 partial responders. No patients developed progressive disease while receiving PCR. This is the first report of a trial in CLL utilizing a combination of purine analog, alkylator, and rituximab, in which most patients were older than 65 years and had high-risk disease. PCR is active in CLL/SLL, but appears to be less active and associated with more complications in the community setting, compared to trials with younger, lower risk patients who travel to academic referral centers for treatment.