Catherine G. Lindgren

Adoptive immunotherapy for indolent non-Hodgkin lymphoma and mantle cell lymphoma using genetically modified autologous CD20-specific T cells

Adoptive immunotherapy with T cells expressing a tumor-specific chimeric T-cell receptor is a promising approach to cancer therapy that has not previously been explored for the treatment of lymphoma in human subjects. We report the results of a proof-of-concept clinical trial in which patients with relapsed or refractory indolent B-cell lymphoma or mantle cell lymphoma were treated with autologous T cells genetically modified by electroporation with a vector plasmid encoding a CD20-specific chimeric T-cell receptor and neomycin resistance gene. Transfected cells were immunophenotypically similar to CD8(+) effector cells and showed CD20-specific cytotoxicity in vitro. Seven patients received a total of 20 T-cell infusions, with minimal toxicities. Modified T cells persisted in vivo 1 to 3 weeks in the first 3 patients, who received T cells produced by limiting dilution methods, but persisted 5 to 9 weeks in the next 4 patients who received T cells produced in bulk cultures followed by 14 days of low-dose subcutaneous interleukin-2 (IL-2) injections. Of the 7 treated patients, 2 maintained a previous complete response, 1 achieved a partial response, and 4 had stable disease. These results show the safety, feasibility, and potential antitumor activity of adoptive T-cell therapy using this approach. This trial was registered at www.clinicaltrials.gov as #NCT00012207.

Influence of dose and duration of infusion of interleukin-2 on toxicity and immunomodulation.

The purpose of this study was to investigate the effect of dose and duration of infusion of recombinant interleukin-2 (IL-2) on toxicity and immunomodulation. In a phase I/II study, IL-2 was administered intravenously (IV) daily for five consecutive days every other week for 4 weeks of treatment to 23 patients with progressive melanoma, renal, colon, or ovarian cancer by one of four regimens: groups I and II received 3 X 10(5) U/m2/d by two-hour or 24-hour infusion, respectively; groups III and IV received 3 X 10(6) U/m2/d by two-hour or 24-hour infusion, respectively. In a subsequent study, six patients (group V) received a single priming cycle of daily IL-2 for five days at 3 X 10(6) U/m2/d in divided 15-minute infusions every eight hours, before undergoing leukapheresis for lymphokine-activated killer (LAK) cell generation. Toxicity was mild with 3 X 10(5) U/m2/d, but severe chills and fever, moderate hypotension (not requiring IV pressors), and weight gain were observed with 3 X 10(6) U/m2/d. Toxicity was also related to the duration of infusion. In group IV (continuous infusion), fluid retention, weight gain, and azotemia were more frequent and severe than in groups III or V, in which the same total dose was administered by two-hour infusion or in three divided 15-minute infusions. IL-2 induced rebound lymphocytosis, which was directly dose-related and significantly higher in group IV (continuous infusion) than in groups III or V. Dramatic increases in the percentage and absolute number of cells expressing the IL-2 receptor were also most pronounced in group IV. With the higher dose of IL-2, LAK cells appeared in the circulation, and natural killer (NK) cytotoxicity was augmented. The results showed that the toxicity and immunomodulation by IL-2 are dose-dependent and are maximal by continuous infusion compared with two-hour or divided every eight hours infusions.

Subcutaneous recombinant gamma interferon in cancer patients: toxicity, pharmacokinetics, and immunomodulatory effects

SummaryRecombinant gamma interferon (rγ-IFN) was administered s. c. daily to 26 patients with advanced cancer. Patients were assigned to one of six doses: 0.5, 1, 2, 4, 6, or 8 million units (MU)/m2 per d. The major toxicities were an influenza-like syndrome and fever, seen in all patients. Dose limiting toxicity occurred in 4 of 4 patients treated at 8 MU/m2. One patient with nodular poorly differentiated lymphocytic lymphoma had a mixed response, and two patients with renal cell cancer have had stabilization of disease for >10 and >12 months. Pharmacokinetic analysis, by radioimmunoassay, revealed mean serum rγ-IFN concentrations up to 17 ng/ml, with maximal serum levels noted 6 to 13 h after injection. In vivo immunomodulation was assessed by natural killer (NK) cytotoxicity, monocyte activation as determined by cell surface expression of HLA-Dr, and peripheral blood mononuclear cell phenotype analysis by flow cytometry. The mean T4/T8 ratio increased from 2.1 pretreatment to 4.1 after 24 h of treatment, but returned to baseline after 7 and 28 days of treatment. Augmentation of NK function was noted after 7 days of treatment. Monocyte cell surface expression of HLA-Dr increased after 28 days of treatment at the three lowest doses. In conclusion, daily s. c. rγ-IFN can be easily administered on an outpatient basis with minimal local skin toxicity, results in prolonged serum levels, and is associated with immunological changes of potential antitumor significance. Further study of the in vivo immunomodulatory effects induced by rγ-IFN is indicated to help define the optimal treatment regimen.

Interleukin-2 after autologous stem cell transplantation for hematologic malignancy : a phase I/II study

The success of autologous stem cell transplantation (ASCT) for hematologic malignancy is limited largely by a high relapse rate. It is postulated that IL-2 administered after ASCT may eliminate minimal residual disease and thereby reduce relapses. A phase I/II study was performed to identify a regimen of IL-2 (Chiron) that could be given early after ASCT in phase III trials. In the phase I study, beginning a median of 46 days after ASCT for hematologic malignancy, cohorts of three to four patients received escalating doses of ‘induction’ IL-2 of 9, 10, or 12 × 106 IU/m2/day for 4 or 5 days by continuous i.v. infusion (CIV), followed by a 4-day rest period, and then 1.6 × 106 IU/m2/day of maintenance IL-2 by CIV for 10 days. The maximum tolerated dose (MTD) of induction IL-2 was 9 × 106 IU/m2/day × 4. In the phase II study, 52 patients received the MTD. Eighty percent of patients completed induction IL-2. Most patients exhibited some degree of capillary leak. One patient died of CMV pneumonia and one died of ARDS. Maintenance IL-2 was well tolerated. In the phase I/II study, 16 of 31 patients with non-Hodgkin lymphoma (NHL), 3/8 with Hodgkin disease (HD), 4/17 with AML, and 4/5 with ALL remain in CR. Two of six multiple myeloma (MM) patients remain in PR. Although the regimen of IL-2 identified had significant side-effects in some patients, it was well tolerated in the majority of patients. Phase III prospectively randomized clinical trials are in progress to determine if this IL-2 regimen will decrease the relapse rate after ASCT for AML and NHL.

Interleukin-2 +/- lymphocytes as consolidative immunotherapy after autologous bone marrow transplantation for hematologic malignancies.

Patients who undergo autologous bone marrow transplantation (ABMT) for advanced hematologic malignancies experience a high relapse rate. Therapy with interleukin-2 (IL-2) +/- lymphokine-activated killer (LAK) cells has induced clinical responses in some patients with advanced malignant lymphoma (ML) or acute myelogenous leukemia (AML). It is postulated that IL-2 +/- LAK cells represents a potentially non-cross-resistant therapeutic modality which might prevent or delay relapses if used as consolidative immunotherapy after ABMT, at a time of minimal residual disease. Therefore, we first studied the reconstitution of IL-2-responsive LAK precursor cells after ABMT and found them in the circulation as early as 3 weeks after ABMT. A phase Ib clinical trial was then performed which identified a tolerable IL-2 regimen which could be administered early after ABMT and which could induce immunomodulatory effects. We then initiated a clinical trial to determine the feasibility of generating and administering autologous LAK cells using this IL-2 regimen after ABMT for 16 patients with ML. The results show that IL-2+LAK therapy early after ABMT is feasible but is more toxic than IL-2 alone. Patients with AML on the phase I IL-2 trial and with ML on the IL-2+LAK protocol were evaluated for tumor status. Of 8 patients with AML in first relapse or at a later stage who underwent ABMT and received IL-2, 2 have relapsed, while 6 remain in complete remission 26+ to 40+ (median 28+) months after ABMT. Of 16 patients with ML considered at high risk for relapse who were treated with ABMT+IL-2+LAK, 5 have relapsed, while 11 remain in complete remission at 6+ to 21+ (median 10+) months after ABMT. The results in both trials are quite encouraging and appear to be better than those in nonrandomized historical controls at our institution. Prospectively randomized trials of IL-2 versus no IL-2 after ABMT in such patients are being initiated to assess definitively the effect, if any, on the relapse rate.

Interleukin-12 induced cytolytic activity in lymphocytes from recipients of autologous and allogeneic stem cell transplants

Interleukin-12 (IL-12) has been reported to enhance the cytolytic activity of NK and activated T cells and to induce low levels of lymphokine-activated killer (LAK) activity in normal human lymphocytes. Therapy with IL-12 has induced tumor eradication in murine models. These observations suggest that IL-12 might have a role as treatment for minimal residual disease following transplantation. To determine whether PBL from recipients of autologous (autoSCT) and allogeneic (alloSCT) bone marrow or peripheral blood stem cell transplants respond to IL-12 with generation of LAK activity, PBL were incubated with IL-12 for 5 days, then tested in a 51Cr release assay for lysis of Daudi. PBL from 17 normal ‘control’ individuals were similarly tested and lysis was observed in only 3/17 (mean 16.9% of the three). By contrast, PBL from 10/12 patients obtained a median of 30 days after autoSCT, exhibited significant IL-12-induced LAK activity (mean lysis, 35.3%, P < 0.005 vs controls). PBL from 18 of 20 patients tested a median of 44 days after alloSCT also exhibited significant LAK activity (mean lysis, 30.0%, P < 0.005 vs controls). In autoSCT recipients, IL-12 and IL-2 at high concentrations (1000 U/ml each) were additive for induction of LAK activity, whereas low, suboptimal concentration of IL-12 (250 U/ml) and IL-2 (1 U/ml) were synergistic in 3/5 experiments. The percentage of PBL expressing IL-12 receptor β 1 chain (IL-12rβ 1) was higher in stem cell recipients than in normal individuals, P < 0.05. moreover, a higher percentage of il-12rβ 1-positive PBL was associated with greater IL-12-induced LAK activity in transplant recipients. These studies demonstrate that PBL obtained early after stem cell transplantation have a higher percentage of cells expressing IL-12rβ 1 and respond to IL-12 with significantly greater LAK cytotoxicity than PBL from normal controls. These results suggest that IL-12 is a potentially attractive candidate for study as consolidative immunotherapy after stem cell transplantation.

Growth and autologous tumor lysis by tumor-infiltrating lymphocytes from metastatic melanoma expanded in interleukin-2 or interleukin-2 plus interleukin-4

Optimal conditions for expanding tumor-infiltrating lymphocytes (TILs) specifically cytotoxic for autologous melanoma for clinical use have not yet been identified. In several small studies, interleukin (IL)-4 was reported to promote the growth of such TILs in IL-2. Given the potential implications for TIL therapy, we attempted to confirm these findings in a larger study. Baseline data were first obtained on the proliferation, immunophenotype, and cytotoxic reactivity to autologous melanoma of TILs cultured in IL-2 alone. Similar studies were performed with TIL cultured concurrently in either IL-2 alone or in a combination of IL-2 and IL-4. TILs were obtained by excisional biopsy of tumors from 52 patients with metastatic malignant melanoma; TILs from 38 patients were expanded in IL-2 (1,000 U/ml). TILs from 19 biopsies were maximally expanded 6- to 24,000-fold (median, 300-fold) over 4-10 weeks. Expansion did not correlate with the weight of, or number of lymphocytes in, the biopsy specimen, or the site of the biopsy (lymph node vs. subcutaneous metastases). During weeks 5-8, TILs from 19 of 25 biopsy specimens lysed autologous melanoma with little or no lysis of allogeneic melanoma. Lysis of autologous tumor was blocked by antibody to class I antigens. Twenty-four TIL specimens were cultured concurrently in IL-2 alone and in IL-2 plus IL-4 and tested for growth and for lysis of autologous and allogeneic melanomas.(ABSTRACT TRUNCATED AT 250 WORDS)

IL-2-BASED CONSOLIDATIVE IMMUNOTHERAPY AFTER AUTOLOGOUS BONE MARROW TRANSPLANTATION

The success of autologous bone marrow transplantation (ABMT) for advanced hematologic malignancies is limited largely by a high incidence of relapse of the malignancy after ABMT.1, 2, 3, 4, 5, 6,7 The relapses may reflect the failure of the chemoradiotherapy to eradicate all residual disease and, possibly, the outgrowth of clonogenic tumor cells contaminating the infused autologous marrow. Therapy with Interleukin-2 (IL-2), with or without lymphokine-activated killer (LAK) cells, has been reported to induce regressions of advanced cancer in some patients.8,9,10,11 There are several reasons for postulating that IL-2 +/- LAK cells administered as consolidative immunotherapy early after ABMT for hematologic malignancies might decrease the relapse rate. (a) Human acute leukemia or lymphoma cells are known to be susceptible to LAK cell-mediated lysis in vitro,12,13,14 and some patients with advanced hematologic malignancies have been reported to respond to therapy with high-dose IL-2 with or without LAK cells.8,9,15,16 Indeed, a review of eight trials of IL-2 +/- LAK cells for malignant lymphoma in relapse reveals an overall 20% response rate.17 Moreover, some patients with acute myelogenous leukemia (AML) refractory to chemotherapy have also responded to IL-2 therapy.18,19,20,21 (b) Such immunotherapy is potentially non-cross-resistant with chemoradiotherapy. (c) A state of minimal residual disease is readily attained by the conditioning regimens used for ABMT--a setting in which immunotherapy should theoretically be more effective. (d) IL-2/LAK therapy after ABMT should theoretically be able to eradicate whatever clonogenic malignant cells might be present in the stored marrow and thus should obviate the need for purging the marrow of tumor cells. (e) The possibility exists that a graftversus-leukemia (GVL) effect may exist in recipients of autologous marrow and might be amplified by IL-2 and/or lymphocytes.

Use of IL-2 and Lymphocytes Following Bone Marrow Transplantation

High-dose chemoradiotherapy and bone marrow transplantation (BMT) can cure some patients with acute leukemia or lymphoma refractory to conventional therapy [1]. The success of BMT is limited largely by a high relapse rate [1]. Attempts to use additional chemotherapy or radiation to decrease the relapse rate have been hampered by the cross-resistance of the tumor to the various agents and by their shared cumulative side effects. The systemic administration of IL-2 with or without reinfusion of ex vivo-generated LAK cells [2] represents one possible consolidative treatment modality which, if used after BMT, might exert an anti-tumor effect against the minimal residual disease which is assumed to persist after BMT, and thereby prevent or delay recurrence of the malignancy.