Andrew Pecora

Administration of rhIL-7 in humans increases in vivo TCR repertoire diversity by preferential expansion of naive T cell subsets

Interleukin-7 (IL-7) is a homeostatic cytokine for resting T cells with increasing serum and tissue levels during T cell depletion. In preclinical studies, IL-7 therapy exerts marked stimulating effects on T cell immune reconstitution in mice and primates. First-in-human clinical studies of recombinant human IL-7 (rhIL-7) provided the opportunity to investigate the effects of IL-7 therapy on lymphocytes in vivo. rhIL-7 induced in vivo T cell cycling, bcl-2 up-regulation, and a sustained increase in peripheral blood CD4+ and CD8+ T cells. This T cell expansion caused a significant broadening of circulating T cell receptor (TCR) repertoire diversity independent of the subjects age as naive T cells, including recent thymic emigrants (RTEs), expanded preferentially, whereas the proportions of regulatory T (T reg) cells and senescent CD8+ effectors diminished. The resulting composition of the circulating T cell pool more closely resembled that seen earlier in life. This profile, distinctive among cytokines under clinical development, suggests that rhIL-7 therapy could enhance and broaden immune responses, particularly in individuals with limited naive T cells and diminished TCR repertoire diversity, as occurs after physiological (age), pathological (human immunodeficiency virus), or iatrogenic (chemotherapy) lymphocyte depletion.

Phase I Trial of Intravenous Administration of PV701, an Oncolytic Virus, in Patients With Advanced Solid Cancers

PURPOSEnPV701, a replication-competent strain of Newcastle disease virus, causes regression of tumor xenografts after intravenous administration. This phase I study was designed to define the maximum-tolerated dose (MTD) and safety of single and multiple intravenous doses of PV701 as a single agent in patients with cancer.nnnPATIENTS AND METHODSnSeventy-nine patients with advanced solid cancers that were unresponsive to standard therapy were enrolled. Four PV701 intravenous dosing regimens were evaluated: (1) single dose: one dose every 28 days; (2) repeat dose: three doses in 1 week every 28 days; (3) desensitizing: one lower dose followed by two higher doses in 1 week every 28 days; and (4) two week: one lower dose followed by five higher doses over 2 weeks every 21 days.nnnRESULTSnA 100-fold dose intensification was achieved over 195 cycles. A first-dose MTD of 12 x 10(9) plaque-forming units (PFU)/m(2) was established for outpatient dosing. After an initial dose of 12 x 10(9) PFU/m(2), patients tolerated an MTD for subsequent doses of 120 x 10(9) PFU/m(2). The most common adverse events were flu-like symptoms that occurred principally after the first dose and were decreased in number and severity with each subsequent dose. Tumor site-specific adverse events and acute dosing reactions were also observed but not cumulative toxicity. Objective responses occurred at higher dose levels, and progression-free survival ranged from 4 to 31 months. Tumor tissue from one patient was obtained after 11 months of therapy and showed evidence of PV701 particles budding from the tumor cell membrane by electron microscopy and a pronounced lymphoplasmacytic infiltrate by histologic examination.nnnCONCLUSIONnPV701 warrants further study as a novel therapeutic agent for cancer patients.

Incidence and Clinical Complications of Myelodysplastic Syndromes Among United States Medicare Beneficiaries

PURPOSEnTo determine the incidence and complications of myelodysplastic syndromes (MDS) among Medicare beneficiaries.nnnMETHODSnRetrospective review of 2003 Medicare Standard Analytic Files utilizing International Classification of Diseases for Oncology ninth edition CM code 238.7 to identify new MDS patients, with 3-year follow-up.nnnRESULTSnAmong 1,394,343 individuals in Medicare Standard Analytic Files age > or = 65 years, 162 per 100,000 were coded as newly diagnosed MDS during 2003 yielding a calculated 45,000 new cases in the United States Medicare > or = 65 years population. Patients with MDS were older (median age, 77 years), and over-represented by males. Among patients with MDS diagnosed during first quarter of 2003, 73.2% suffered cardiac-related events during 3-year follow-up, which exceeded the Medicare population (54.5%; P < .01) even when age adjusted (odds ratio, 2.10; P < .01). Significant increases in prevalence of diabetes (40.0% v 33.1%), dyspnea (49.4% v 28.5%), hepatic diseases (0.8% v 0.2%), and infections (sepsis: 22.5% v 6.1%) were noted in MDS (all P < .01) compared with the Medicare population. Patients with MDS requiring RBC transfusions had greater prevalence of these comorbidities. Acute myeloid leukemia developed within 3 years in 9.6%, with increased transformation among transfused (24.6%; P < .001). The 3-year Kaplan-Meier age-adjusted survival for MDS was 60.0%, which was significantly lower than the Medicare population (84.7%; hazard ratio, 3.08; P < .001), and mortality was further increased among transfused MDS (P < .01). In 2003, median payment for MDS was

Phase I Study of Recombinant Human Interleukin-7 Administration in Subjects with Refractory Malignancy

16,181, compared to

PROMPT AND DURABLE ENGRAFTMENT IN TWO OLDER ADULT PATIENTS WITH HIGH RISK CHRONIC MYELOGENOUS LEUKEMIA (CML) USING EX VIVO EXPANDED AND UNMANIPULATED UNRELATED UMBILICAL CORD BLOOD

1,575 for the Medicare population (P < .001).nnnCONCLUSIONnMDS is a common hematologic malignancy of the elderly, which places patients at risk for comorbid conditions. Transfusion dependency identifies patients with MDS at additional increased risk of organ impairment and shortened survival.

High-Dose Versus Standard Chemotherapy in Metastatic Breast Cancer: Comparison of Cancer and Leukemia Group B Trials With Data From the Autologous Blood and Marrow Transplant Registry

Purpose: Interleukin-7 (IL-7) has critical and nonredundant roles in T-cell development, hematopoiesis, and postdevelopmental immune functions as a prototypic homeostatic cytokine. Based on a large body of preclinical evidence, it may have multiple therapeutic applications in immunodeficiency states, either physiologic (immunosenescence), pathologic (HIV), or iatrogenic (postchemotherapy and posthematopoietic stem cell transplant), and may have roles in immune reconstitution or enhancement of immunotherapy. We report here on the toxicity and biological activity of recombinant human IL-7 (rhIL-7) in humans. Design: Subjects with incurable malignancy received rhIL-7 subcutaneously every other day for 2 weeks in a phase I interpatient dose escalation study (3, 10, 30, and 60 μg/kg/dose). The objectives were safety and dose-limiting toxicity determination, identification of a range of biologically active doses, and characterization of biological and, possibly, antitumor effects. Results: Mild to moderate constitutional symptoms, reversible spleen and lymph node enlargement, and marked increase in peripheral CD3+, CD4+, and CD8+ lymphocytes were seen in a dose-dependent and age-independent manner in all subjects receiving ≥10 μg/kg/dose, resulting in a rejuvenated circulating T-cell profile, resembling that seen earlier in life. In some subjects, rhIL-7 induced in the bone marrow a marked, transient polyclonal proliferation of pre-B cells showing a spectrum of maturation as well as an increase in circulating transitional B cells. Conclusion: This study shows the potent biological activity of rhIL-7 in humans over a well-tolerated dose range and allows further exploration of its possible therapeutic applications. Clin Cancer Res; 16(2); 727–35

CD34+CD33- cells influence days to engraftment and transfusion requirements in autologous blood stem-cell recipients.

Delayed engraftment, graft failure, and adverse transplant-related events have been observed in unrelated umbilical cord blood (UCB) recipients, particularly in those receiving a low leukocyte cell dose and in CML patients. We report the outcomes of two older adult patients with high risk CML who received a low leukocyte cell dose of unmanipulated UCB cells supplemented with ex vivo expanded (AastromReplicell System) UCB cells. Each engrafted promptly and neither patient experienced GVHD or life-threatening infection. Both remain engrafted with cells exclusively of donor origin and are in cytogenetic remission at 19 and 8 months follow-up. Ex vivoexpanded UCB cells appear to facilitate hematopoietic recovery and therefore may increase the number of CML patients eligible for unrelated UCB transplant. Bone Marrow Transplantation (2000) 25, 797–799.

Impact of pre-transplant rituximab on survival after autologous hematopoietic stem cell transplantation for diffuse large B cell lymphoma.

PURPOSEnTo assess survival of patients with metastatic breast cancer treated with high-dose chemotherapy (HDC) versus standard-dose chemotherapy (SDC).nnnPATIENTS AND METHODSnSDC in four Cancer and Leukemia Group B (CALGB) trials was compared with hematopoietic stem-cell support in patients from the Autologous Blood and Marrow Transplant Registry. Cox proportional hazard regression incorporated potentially confounding effects. A total of 1,509 women were enrolled onto CALGB trials, and 1,188 women received HDC. No significant survival differences existed by CALGB trial or HDC regimen. Consideration was restricted to candidates for both SDC and HDC. The resulting sample included 635 SDC and 441 HDC patients. The outcome of interest was overall survival.nnnRESULTSnThe HDC group displayed better performance status. The SDC group had slightly better survival in first year after treatment. The HDC group had lower hazard of death from years 1 to 4 and had somewhat higher probability of 5-year survival (adjusted probabilities [95% confidence intervals], 23% [17% to 29%] v 15% [11% to 19%], P =.03).nnnCONCLUSIONnAfter controlling for known prognostic factors in this nonrandomized analysis of two large independent data sets, women receiving HDC versus SDC for metastatic breast cancer have a similar short-term probability of survival, and might have a modestly higher long-term probability of survival.

Phase I trial of bortezomib in combination with rituximab-HyperCVAD alternating with rituximab, methotrexate and cytarabine for untreated aggressive mantle cell lymphoma

PURPOSEnTo evaluate the reliability of CD34/CD33 subset enumeration as a predictor of hematopoietic repopulating potential in autologous blood stem-cell transplantation and to determine which patient and treatment-related factors affect the timing, quantity, and type of blood stem cells mobilized.nnnPATIENTS AND METHODSnWe analyzed blood stem-cell collections from 410 consecutive cancer patients who received mobilization therapy and evaluated factors, including CD34+ subset quantities, that might influence engraftment kinetics and transfusion requirements in autologous blood stem-cell recipients.nnnRESULTSnThe majority of patients (97%) mobilized CD34+33- cells, which were usually collected in the greatest quantity on the first day of apheresis. Patients who received only growth factor mobilized the highest percentage of CD34+33- cells. Extensive prior chemotherapy limited the collection of CD34+33- cells. In addition to patient diagnosis (P < .006) and total CD34+ cell dose (P = .0001), CD34+33- cell dose (P < .005) and percentage of CD34+33- cells (P < .005) were identified as independent factors significantly predictive of engraftment kinetics. CD34+33- cell dose (R2 < or = .177; P < .0001) was a strong and the only significant predictor of RBC and platelet transfusion requirements. Furthermore, independent of the total CD34+ cell dose, as the CD34+33- cell dose increased, days to neutrophil recovery, days to platelet recovery, and transfusion requirements decreased.nnnCONCLUSIONnThese findings show that CD34+33- cells are readily collected in most cancer patients and significantly influence engraftment kinetics and transfusion requirements in autologous blood stem-cell recipients. CD34+33- cell quantity of the blood stem-cell graft appears to be a more reliable predictor of hematopoietic recovery rates than total CD34+ cell quantity in this setting.

A phase II trial evaluating the safety and effectiveness of the AastromReplicell system for augmentation of low-dose blood stem cell transplantation.

Incorporation of the anti-CD20 monoclonal antibody rituximab into front-line regimens to treat diffuse large B cell lymphoma (DLBCL) has resulted in improved survival. Despite this progress, however, many patients develop refractory or recurrent DLBCL and then undergo autologous hematopoietic stem cell transplantation (AuHCT). It is unclear to what extent pre-transplant exposure to rituximab affects outcomes after AuHCT. Outcomes of 994 patients receiving AuHCT for DLBCL between 1996 and 2003 were analyzed according to whether rituximab was (n = 176; +R cohort) or was not (n = 818; -R cohort) administered with front-line or salvage therapy before AuHCT. The +R cohort had superior progression-free survival (PFS; 50% vs 38%; P = .008) and overall survival (OS; 57% vs 45%; P = .006) at 3 years. Platelet and neutrophil engraftment were not affected by exposure to rituximab. Nonrelapse mortality (NRM) did not differ significantly between the 2 cohorts. In multivariate analysis, the +R cohort had improved PFS (relative risk of relapse/progression or death, 0.64; P < .001) and improved OS (relative risk of death, 0.74; P = .039). We conclude that pre-transplant rituximab is associated with a lower rate of progression and improved survival after AuHCT for DLBCL, with no evidence of impaired engraftment or increased NRM.