Optimizing the use of rituximab for treatment of B-cell non-Hodgkin's lymphoma: a benefit-risk update

Rituximab (Rituxan; Genentech, Inc, South San Francisco, CA and IDEC Pharmaceutical Corporation, San Diego, CA), the first monoclonal antibody approved in the United States for the treatment of cancer, is indicated for the treatment of patients with relapsed or refractory CD20+ low-grade non-Hodgkin's lymphoma. From November 1997 through May 1999, approximately 36,000 patients have been treated with rituximab. Serious cardiopulmonary infusion reactions culminating in death have been reported to occur in approximately 0.04% to 0.07% of patients. Post-approval tumor lysis syndrome has been reported within 12 to 24 hours after the first antibody infusion and is estimated to occur in 0.04% to 0.05% of patients. The risk of tumor lysis appears to be higher in patients with high numbers of circulating malignant cells. Serious infusion-related adverse drug reactions, most often consisting of cardiopulmonary reactions associated with the rapid lysis of large numbers of circulating malignant cells, have been fatal in approximately 0.5 per 1,000 treated patients. Major risk factors include high numbers of circulating malignant lymphoma cells, pulmonary infiltrates or lymphoma involvement, and prior cardiovascular disease. This report updates the safety experience of rituximab therapy with data from clinical trials and postmarketing safety experience, and examines how this information can be used to optimize therapy.

A pilot study of the anti-CD20 monoclonal antibody rituximab in patients with refractory immune thrombocytopenia

We conducted a prospective pilot phase I/II clinical trial to evaluate the toxicity and response rate of the chimeric anti-CD20 monoclonal antibody, rituximab (Rituxan; Genentech, Inc, South San Francisco, CA, and IDEC Pharmaceutical Corporation, San Diego, CA), in the treatment of patients with immune thrombocytopenic purpura. Patients with a clinical diagnosis of idiopathic thrombocytopenic purpura who had failed corticosteroid therapy and whose platelet count was less than 75,000/microL were eligible for the study. Rituximab was administered in a dose-escalation fashion using doses ranging from 50 to 375 mg/m2 weekly for 4 weeks. Thirteen patients have been enrolled on the trial to date and 12 have completed the full course of treatment. No unusual toxicity was noted in this patient population. None of the three patients at the lowest dose level achieved a clinical response. Three of nine patients (30%) who have received rituximab at doses close or equal to the full dose have shown an objective clinical response (two complete responses, one partial response). The study is currently ongoing, and conclusions regarding the overall response rate, clinical parameters that influence response, surrogate markers of response, and the underlying mechanism of response remain to be addressed. The current study should provide answers to a number of important questions regarding the role of rituximab in the treatment of this and other autoimmune disorders.

Exceptional familial clustering for extreme longevity in humans

Four families highly clustered for extreme longevity are described here, representing the first report of clustering for this phenotype. Families such as these may prove to be helpful in the further understanding of the genetic contribution to achieving exceptional longevity.

High-dose recombinant interleukin-2 therapy in patients with metastatic melanoma: long-term survival update

PURPOSE

To update response duration and survival data for patients with metastatic melanoma receiving the high-dose IV bolus recombinant interleukin (IL)-2 regimen.

PATIENTS AND METHODS

Two hundred seventy assessable patients were entered into eight clinical trials conducted between 1985 and 1993. IL-2 600,000 or 720,000 IU/kg was administered by 15-minute intravenous infusion every 8 hours for up to 14 consecutive doses over 5 days as clinically tolerated with maximum support, including pressors. A second, identical cycle of treatment was scheduled following 6 to 9 days of rest, and courses could be repeated every 6 to 12 weeks in stable or responding patients. Responding patients received up to five courses (two cycles/course) of treatment. All data were updated through December 1998 using report forms completed by the clinical investigators.

RESULTS

The objective overall response rate was unchanged from the previous report. Tumor responses were seen in 16% of patients, with complete responses in 17 (6%) and partial responses in 26 (10%). Median survival for the group as a whole is now 12 months. Median follow-up time for surviving patients exceeds 7 years. Median duration of response for the 43 responding patients and the 26 patients with partial responses remained unchanged at 8.9 and 5.9 months, respectively. Response durations ranged from 1.5 to > 122 months. The median duration of complete responses has yet to be reached, but is at least 59 months. Thirty-one patients (11%) were alive as of last contact; 28 were confirmed, including 18 responding patients. Three patients were lost to follow-up at > 1, > 13, and > 104 months. Twelve responding patients remained continually disease- or progression-free from > 70 to > 150 months following initiation of therapy. Disease progression was not observed in any patient who was responding as of the last report or in any patient responding for longer than 30 months.

CONCLUSION

These data continue to support the notion that high-dose IL-2 produces durable responses in some patients with metastatic melanoma and should be considered a therapeutic option for appropriately selected patients with this disease.

High-dose recombinant interleukin 2 therapy for patients with metastatic melanoma: analysis of 270 patients treated between 1985 and 1993

PURPOSE

To determine the short- and long-term efficacy and toxicity of the high-dose intravenous bolus interleukin 2 (IL-2) regimen in patients with metastatic melanoma.

PATIENTS AND METHODS

Two hundred seventy assessable patients were entered onto eight clinical trials conducted between 1985 and 1993. IL-2 (Proleukin [aldesleukin]; Chiron Corp, Emeryville, CA) 600,000 or 720,000 IU/kg was administered by 15-minute intravenous infusion every 8 hours for up to 14 consecutive doses over 5 days as clinically tolerated with maximum support, including pressors. A second identical treatment cycle was scheduled after 6 to 9 days of rest, and courses could be repeated every 6 to 12 weeks in stable or responding patients. Data were analyzed through fall 1996.

RESULTS

The overall objective response rate was 16% (95% confidence interval, 12% to 21%); there were 17 complete responses (CRs) (6%) and 26 partial responses (PRs) (10%). Responses occurred with all sites of disease and in patients with large tumor burdens. The median response duration for patients who achieved a CR has not been reached and was 5.9 months for those who achieved a PR. Twelve (28%) of the responding patients, including 10 (59%) of the patients who achieved a CR, remain progression-free. Disease did not progress in any patient responding for more than 30 months. Baseline performance status and whether patients had received prior systemic therapy were the only predictive prognostic factors for response to IL-2 therapy. Toxicities, although severe, generally reversed rapidly after therapy was completed. Six patients (2%) died from adverse events, all related to sepsis.

CONCLUSION

High-dose IL-2 treatment seems to benefit some patients with metastatic melanoma by producing durable CRs or PRs and should be considered for appropriately selected melanoma patients.

Prevalence and predictors of the use of self-care resources

Health care reform goals are to reduce costs and increase access while maintaining quality of care. A potentially effective avenue for achieving these difficult goals is to activate the untapped potential of consumers in managing their own health care. This study focuses on three Northwest communities and examines the prevalence of the use of self-care resources and the correlates of use. A random sample of households was surveyed using a mail-out questionnaire. The findings indicated that the use of self-care resources was high in the three community populations. Consulting a self-care book was the most commonly used resource, followed by telephone advice nurses. Communities do vary in their level of self-care resource use. Understanding this variability may help communities to expand the use of such resources and lessen the demand for formal health care services. Suggestions for future studies are discussed.

High-dose chemotherapy followed by reinfusion of selected CD34+ peripheral blood cells in patients with poor-prognosis breast cancer: a randomized multicentre study

Seventy-one patients with poor-prognosis breast cancer were enrolled after informed consent in a multicentre randomized study to evaluate the use of selected peripheral blood CD34+ cells to support haematopoietic recovery following high-dose chemotherapy. Patients who responded to conventional chemotherapy were mobilized with chemotherapy (mainly high-dose cyclophosphamide) and/or recombinant human granulocyte colony-stimulating factor (rhG-CSF). Patients who reached the threshold of 20 CD34+ cells per microl of peripheral blood underwent apheresis and were randomized at that time to receive either unmanipulated mobilized blood cells or selected CD34+ cells. For patients in the study arm, CD34+ cells were selected from aphereses using the Isolex300 device. Fifteen patients failed to mobilize peripheral blood progenitors and nine other patients were excluded for various reasons. Forty-seven eligible patients were randomized into two comparable groups. CD34+ cells were selected from aphereses in the study group. Haematopoietic recovery occurred at similar times in both groups. No side-effect related to the infusion of selected cells was observed. The frequency of epithelial tumour cells in aphereses was low (8 out of 42 evaluated patients), as determined by immunocytochemistry. We conclude that selected CD34+ cells safely support haematopoietic recovery following high-dose chemotherapy in patients with poor-prognosis breast cancer.

Treatment of indolent lymphoma with fludarabine/mitoxantrone combination: a phase II trial

In an effort to reduce the risk of opportunistic infections, 25 patients with advanced indolent lymphoma (age range: 30-77 years) were treated, using a combination of fludarabine and mitoxantrone, without corticosteroids. Fludarabine was given at 25 mg/m2 for three daily doses, and mitoxantrone at 10 mg/m2. Cycles were repeated every four weeks for up to maximum response, and for no more than six months. Eight patients had follicular lymphoma, and 11 had CLL/SLL. Objective response was observed in 11 of 12 previously untreated patients, including five complete remissions, and in 10 of 13 previously treated patients, including three complete remissions. Only two relapsed patients failed to respond, whereas two patients were not evaluable. Hence, the overall response rate based on the intention-to-treat analysis was 84 per cent (95 per cent CI: 70-98 per cent). The median survival has not been reached after a 22-month follow-up. Median time to progression was 15 months. One patient on corticosteroids developed pneumocystis carinii pneumonia, and an elderly patient succumbed to neutropenic sepsis. Apart from granulocytopenia, the treatment was well tolerated. Omission of corticosteroids reduces the risk of opportunistic infections, while the activity of the combination against indolent lymphoma and CLL is maintained.

Aberrations of the B-cell receptor B29 (CD79b) gene in chronic lymphocytic leukemia

Leukemic B cells in chronic lymphocytic leukemia (B-CLL) typically exhibit low or undetectable surface Ig. Because the B29 (CD79b and Ig beta) and mb-1 (CD79a and Ig alpha) gene products are required for surface Ig display in the B-cell receptor complex (BCR), we analyzed the expression of these genes in B-CLL cells. The majority (83%) of the randomly selected B-CLL patient samples analyzed exhibited low or undetectable surface BCR measured by mu heavy chain and B29 expression. Levels of mb-1 mRNA in these B-CLL samples with low surface BCR were similar to those in normal B cells. Among those with decreased surface expression, B29 mRNA was not detected in half of these B-CLL samples. The remaining B-CLL samples with diminished surface BCR contained normal levels of B29 mRNA. Further analysis of cDNA clones from the majority of these latter samples contained point mutations, insertions, or deletions that were largely located in the B29 transmembrane and cytoplasmic domains. These results indicate the occurrence of somatic mutations predicted to affect B29 expression and/or function in the majority of B-CLL and suggest that these aberrations underlie the diminished surface BCR display and loss of BCR signaling characteristic of this leukemia.

Whole-body FDG-PET imaging for staging of Hodgkin's disease and lymphoma

Accurate staging of Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) is important for treatment management. In this study, the utility of 2-[18F]fluoro-2-deoxy-D-glucose (FDG) whole-body PET was evaluated as an imaging modality for initial staging or restaging of 7 HD and 11 NHL patients.

METHODS

Whole-body PET-based staging results were compared to the patient's clinical stage based on conventional staging studies, which included combinations of CT of the chest, abdomen and pelvis, MRI scans, gallium scans, lymphangiograms, staging laparatomies and bone scans.

RESULTS

Accurate staging was performed in 17 of 18 patients using a whole-body PET-based staging algorithm compared to the conventional staging algorithm in 15 of 18 patients. In 5 of 18 patients, whole-body PET-based staging showed additional lesions not detected by conventional staging modalities, whereas conventional staging demonstrated additional lesions in 4 of 18 patients not detected by whole-body PET. The total cost of conventional staging was $66,292 for 16 CT chest scans, 16 CT abdominal/pelvis scans, three limited MRI scans, four bone scans, five gallium scans, two laparotomies and one lymphangiogram. In contrast, scans cost $36,250 for 18 whole-body PET studies and additional selected correlative studies: one plain film radiograph, one limited CT, one bone marrow scan, one upper GI and one endoscopy.

CONCLUSION

A whole-body FDG-PET-based staging algorithm may be an accurate and cost-effective method for staging or restaging HD and NHL.

Clinical characteristics predict response to antithymocyte globulin in paroxysmal nocturnal haemoglobinuria

Seven patients with paroxysmal nocturnal haemoglobinuria (PNH) were treated with antithymocyte globulin (ATG). Each patient received ATG (20 mg/kg/d) for 8 d and prednisone to prevent or control serum sickness. Three patients experienced a sustained improvement in at least one peripheral blood cytopenia, including one patient who had a complete trilineage response. Several pretreatment clinical features appeared to be associated with response to ATG. All responding patients had hypoproliferative features including depressed platelet counts (< 30 x 10(9)/l), and a minor degree of chronic haemolysis as indicated by relatively low reticulocyte counts (< 100 x 10(9)/l), lactate dehydrogenase (< 1000 U/l) and total bilirubin (< 17 mumol/l) levels. Responding patients continued to have chronic low-grade haemolysis after their response to immunosuppression that was similar to that observed prior to treatment. The non-responding patients had a classic haemolytic form of PNH characterized by elevated reticulocyte counts (> 100 x 10(9)/l), lactate dehydrogenase (> 2000 U/l) and total bilirubin (> 17 mumol/l) levels. The impaired haemopoiesis that occurs in hypoproliferative PNH may respond to ATG treatment, but the haemolytic component of the disease, and hence the PNH clone, is not altered by immunosuppressive therapy.

Expression and cytokine regulation of glucocorticoid receptors in Kaposi's sarcoma

Development of Kaposi's sarcoma (KS) after glucocorticoid therapy has been observed in a variety of clinical states including human immunodeficiency virus-1 infection and recent in vitro studies provided evidence for a direct stimulation effect of glucocorticoid hormones on KS cell proliferation. The importance of glucocorticoids in KS pathogenesis is further highlighted by the finding that glucocorticoids synergize with cytokines to promote acquired immune deficiency syndrome (AIDS)-associated KS (AIDS-KS) growth. Furthermore, cytokine effects were abrogated by the glucocorticoid antagonist RU-486. As glucocorticoid action is mediated through activation of their intracellular cognate receptors, we hypothesized that enhanced responsiveness of AIDS-KS cells to glucocorticoids may be due to elevated glucocorticoid receptor (GR) content. Indeed, high expression of GRs in AIDS-KS tumor biopsies was detected both at the level of mRNA and protein. Quantitative measurements of GRs in these specimens by a sensitive immunoassay showed that GR content was significantly elevated in the tumor tissue (4663 fmol/mg protein) compared with the uninvolved skin of the same patients (2777 fmol/mg protein), both of which were markedly above the normal skin of healthy donors (893 fmol/mg protein). Immunocytochemical analysis confirmed the presence of GRs in the cytoplasm and the nucleus of KS cells. Interestingly, four major KS cytokines, namely interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, and oncostatin M, all of which are known autocrine growth factors for AIDS-KS cells, significantly increased the expression of functional GRs in cultured AIDS-KS cells. The latter result may explain, at least in part, the synergistic effect of glucocorticoid and oncostatin M on AIDS-KS cell proliferation. Thus, the high levels of GR expression in AIDS-KS and the up-regulation of GRs by KS-growth-promoting factors may confer enhanced and sustained sensitivity to the stimulatory effects of glucocorticoids. The data presented also provide molecular bases for therapeutic interventions targeting GRs in this disease.

Allogeneic bone marrow transplantation for Hodgkin's and non-Hodgkin's lymphoma

We studied 23 consecutive patients, median age 34 years, with relapsed or resistant aggressive lymphoma who underwent allogeneic BMT at the UCLA Medical Center Bone Marrow Transplantation Unit from 1 November 1984 to 30 March 1993. All patients were < 50 years of age and had sibling donors who were matched at the HLA-A, B and DR loci. Nine patients had Hodgkin's disease (HD) and 14 had non-Hodgkin's lymphoma (NHL); three of these had low grade histology and 11 had intermediate or high grade lymphoma histology. After a median follow-up of 34 months, eight patients are alive, seven without recurrent lymphoma. Five patients had early deaths. The disease-free survival for the entire group is 26% with an overall survival of 29%. There was no difference in survival rate on the basis of disease or histology. Comparing preparative regimens containing TBI to those without there was no difference in survival rate (P = 0.35). Neither age nor sex was a significant determinant of outcome (P = 0.63 and 0.36, respectively). Disease status at the time of transplantation proved to be the important determinant of outcome. Patients transplanted with chemotherapy sensitive disease (n = 9), defined as a partial or complete response to salvage chemotherapy, had a survival rate of 42%, which was significantly better than those who had refractory disease at transplantation (n = 14), who had a survival rate of 21% (P = 0.006). However, this small, but significant fraction of patients with refractory disease was curable. Thus, our data demonstrate that allogeneic bone marrow transplantation is an effective means of treatment for relapsed or aggressive Hodgkin's and non-Hodgkin's lymphoma.

Immune hemolytic anemia associated with biclonal cold autoagglutinins

A 65-year-old man with bladder outlet obstruction due to prostatic hypertrophy was incidentally discovered to have cold-antibody autoimmune hemolytic anemia (cold-aggluthinin syndrome; CAS) due to autoanti-I (titer 1,024 at 4 degrees C and 64 at 30 degrees C), and a biclonal gammopathy. Immunofixation electrophoresis of serum and a red blood cell eluate revealed the patient's autoantibody to be biclonal IgM kappa and IgA kappa. No underlying cause could be determined to explain the development of either the biclonal gammopathy or the CAS. To our knowledge, this is the first reported case of CAS associated with a biclonal gammopathy and biclonal cold autoagglutinins of the IgM kappa, IgA kappa type.

Molecular heterogeneity of translocations associated with muscular dystrophy

Individual translocation chromosomes from six girls suffering from Duchenne or Becker muscular dystrophy (DMD or BMD) have been isolated in human-mouse somatic cell hybrids. DNA prepared from these hybrids was probed with sequences physically close to the locus; these include a junction fragment from the site of the X:21 translocation (pXJ1) and subclones from the pERT 87 (DXS164) region which are absent in a minority of male DMD patients. Both sets of sequences mapped within the area defined by the translocation breakpoints, confirming their close proximity to the DMD and BMD loci. Furthermore, the X chromosome breakpoints of the translocations can be divided into three categories depending upon their position in relation to the sequences recognised by pXJ1 and pERT 87. The genomic target disrupted by the translocations examined here is a minimum of 176 kb.

Mapping of the X-linked agammaglobulinemia locus by use of restriction fragment-length polymorphism

A molecular linkage analysis in 11 families with X-linked agammaglobulinemia (XLA) localized the XLA gene to the proximal part of the long arm of the human X chromosome. Significant linkage was detected between XLA and loci defined by two polymorphic DNA probes called 19-2 for the DXS3 locus and S21 for the DXS17 locus. Both localize to the region Xq21.3-Xq22. Most likely recombination distances (theta) and associated logarithm of the odds (lod) scores for the XLA-DXS3 and XLA-DXS17 pairs were theta = 0.04 morgans (lod, 3.65) and theta = 0 (lod, 2.17), respectively. Tight linkage between XLA and the locus DXS43 defined by the X short arm probe D2 (localized to Xp22-Xp21) was strongly excluded and we obtained no evidence for significant linkage between XLA and any other X short arm probe. The probe pair 19-2 and S21 should be informative for molecular linkage-based analysis of XLA segregation in the majority of families afflicted with this disorder.

Staphylococcal Protein A column: correlation of mitogenicity of perfused plasma with clinical response

Eleven patients with advanced breast cancer and four with astrocytoma were treated with plasma perfused over columns containing staphylococcal Protein A (SPA). Doses of 5 to 20 mg of SPA were bound to collodion charcoal particles, and this treatment resulted in partial remissions in one patient with astrocytoma and in two patients with breast cancer. Remission duration was 6 wk to 6 mo. Resolution of lymphadenopathy and a decrease in carcinoembryonic antigen were noted in an additional two breast cancer patients. Systemic reactions to infused plasma consisted of fever, chills, and rigors. In brain cancer patients, increased intracranial pressure was also noted. A mitogenic substance was generated in plasma of 11 patients after it was perfused over the SPA charcoal matrix. The mitogenic material induced lymphoproliferation comparable to concanavalin A and required the presence of SPA on the collodion charcoal but was not due to leakage of SPA from the column during plasma perfusion. Of considerable significance was that only patients whose column perfused plasma contained this mitogenic activity exhibited systemic reactions, and five of these patients obtained antitumor responses. This striking correlation implies that the mitogenic factor is an active component of SPA therapy. The ability to demonstrate mitogenicity in column perfused plasma might also be useful for selecting patients amenable to SPA therapy. These findings attest to the therapeutic value of this mode of treatment and provide an initial definition of a mediator of SPA antitumor activity.

Genetic linkage relationships of seven DNA probes with Duchenne and Becker muscular dystrophy

The inheritance of seven restriction fragment length polymorphisms detected by DNA probes has been studied in families with Duchenne and Becker muscular dystrophies (DMD and BMD). The probes used have all been mapped to the short arm of the X-chromosome, four being distal and three proximal to the disease loci located within the Xp21 region. Linkage analysis of the DNA polymorphisms in relation to the two disorders showed similar genetic distances. Data obtained from DMD and BMD families have been combined to give more precise values for the different recombination fractions. Combined use of these polymorphic DNA markers will be of practical value in the genetic counselling of women at risk for Duchenne and Becker muscular dystrophy.