Safety and immunobiological activity of guadecitabine sequenced with ipilimumab in metastatic melanoma patients: The phase Ib NIBIT-M4 study

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Background: DNA hypomethylating agents show broad immuno-modulatory activity in neoplastic cells, and may improve the effectiveness of cancer immunotherapies. The phase 1b NIBIT-M4 trial investigated a previously unexplored therapeutic strategy using the next-generation DNA hypomethylating agent guadecitabine sequenced with ipilimumab for the treatment of advanced melanoma. Methods: Patients with unresectable Stage III/IV melanoma received escalating doses of guadecitabine 30, 45 or 60 mg/m2 subcutaneously on Days 1–5 every three weeks, and ipilimumab 3 mg/kg intravenously on Day 1 every three weeks, starting one week after guadecitabine, for four cycles. Primary endpoints were the safety, tolerability and maximum tolerated dose of treatment; secondary endpoints included immune-related disease control and objective response. Genome-wide methylation, RNA sequencing, and immunohistochemistry analyses were performed on tumor samples collected at baseline, W4 and W12. (NCT02608437). Results: 19 patients were treated and evaluable for safety and efficacy. The most common treatment-related adverse events of any grade were myelotoxicity (n = 17; 89%) and immune-related adverse events (n = 12; 63%). Grade 3 or 4 myelotoxicity occurred in 15 (79%) patients. There were no dose limiting toxicities. Rates of immune-related disease control and objective response were 8/19 (42%) and 5/19 (26%), respectively. Exploratory analyses of tumour samples (n = 8) showed that median CpG site methylation at Week 4 (74.5%) and Week 12 (75.5%) was significantly lower (p < 0.05) than at baseline (80.3%), with a median of 2454 (Week 4) and 4131 (Week 12) differentially expressed genes identified compared to baseline; among the 136 pathways significantly modulated by treatment, the most frequently activated were immune-related. Tumour immune contexture analysis (n = 11) demonstrated up-regulation of Human Leukocyte Antigen (HLA) class I molecules on melanoma cells, and an increase in CD8+, PD-1+ T cells and in CD20+ B cells in post-treatment tumour core specimens. Conclusions: Sequential guadecitabine and ipilimumab is safe and tolerable in patients with metastatic melanoma, and has promising immunological and anti-tumour activity. Clinical trial information: NCT02608437.

Immunomodulatory Properties of DNA Hypomethylating Agents: Selecting the Optimal Epigenetic Partner for Cancer Immunotherapy

DNA hypomethylating agents (DHAs) play a well-acknowledged role in potentiating the immunogenicity and the immune recognition of neoplastic cells. This immunomodulatory activity of DHAs is linked to their ability to induce or to up-regulate on neoplastic cells the expression of a variety of immune molecules that play a crucial role in host-tumor immune interactions. To further investigate the clinical potential of diverse epigenetic compounds when combined with immunotherapeutic strategies, we have now compared the tumor immunomodulatory properties of the first generation DHAs, azacytidine (AZA) and decitabine (DAC) and of the next generation DHA, guadecitabine. To this end, human melanoma and hematological cancer cells were treated in vitro with 1 μM guadecitabine, DAC or AZA and then studied by molecular and flow cytometry analyses for changes in their baseline expression of selected immune molecules involved in different mechanism(s) of immune recognition. Results demonstrated a stronger DNA hypomethylating activity of guadecitabine and DAC, compared to AZA that associated with stronger immunomodulatory activities. Indeed, the mRNA expression of cancer testis antigens, immune-checkpoint blocking molecules, immunostimulatory cytokines, involved in NK and T cell signaling and recruiting, and of genes involved in interferon pathway was higher after guadecitabine and DAC compared to AZA treatment. Moreover, a stronger up-regulation of the constitutive expression of HLA class I antigens and of Intercellular Adhesion Molecule-1 was observed with guadecitabine and DAC compared to AZA. Guadecitabine and DAC seem to represent the optimal combination partners to improve the therapeutic efficacy of immunotherapeutic agents in combination/sequencing clinical studies.

SPIRE - combining SGI-110 with cisplatin and gemcitabine chemotherapy for solid malignancies including bladder cancer: study protocol for a phase Ib/randomised IIa open label clinical trial

BACKGROUND

Urothelial bladder cancer (UBC) accounts for 10,000 new diagnoses and 5000 deaths annually in the UK (Cancer Research UK, http://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/bladder-cancer , Cancer Research UK, Accessed 26 Mar 2018). Cisplatin-based chemotherapy is standard of care therapy for UBC for both palliative first-line treatment of advanced/metastatic disease and radical neoadjuvant treatment of localised muscle invasive bladder cancer. However, cisplatin resistance remains a critical cause of treatment failure and a barrier to therapeutic advance in UBC. Based on supportive pre-clinical data, we hypothesised that DNA methyltransferase inhibition would circumvent cisplatin resistance in UBC and potentially other cancers.

METHODS

The addition of SGI-110 (guadecitabine, a DNA methyltransferase inhibitor) to conventional doublet therapy of gemcitabine and cisplatin (GC) is being tested within the phase Ib/IIa SPIRE clinical trial. SPIRE incorporates an initial, modified rolling six-dose escalation phase Ib design of up to 36 patients with advanced solid tumours followed by a 20-patient open-label randomised controlled dose expansion phase IIa component as neoadjuvant treatment for UBC. Patients are being recruited from UK secondary care sites. The dose escalation phase will determine a recommended phase II dose (RP2D, primary endpoint) of SGI-110, by subcutaneous injection, on days 1-5 for combination with GC at conventional doses (cisplatin 70 mg/m2, IV infusion, day 8; gemcitabine 1000 mg/m2, IV infusion, days 8 and 15) in every 21-day cycle. In the dose expansion phase, patients will be randomised 1:1 to GC with or without SGI-110 at the proposed RP2D. Secondary endpoints will include toxicity profiles, SGI-110 pharmacokinetics and pharmacodynamic biomarkers, and pathological complete response rates in the dose expansion phase. Analyses will not be powered for formal statistical comparisons and descriptive statistics will be used to describe rates of toxicity, efficacy and translational endpoints by treatment arm.

DISCUSSION

SPIRE will provide evidence for whether SGI-110 in combination with GC chemotherapy is safe and biologically effective prior to future phase II/III trials as a neoadjuvant therapy for UBC and potentially in other cancers treated with GC.

TRIAL REGISTRATION

EudraCT Number: 2015-004062-29 (entered Dec 7, 2015) ISRCTN registry number: 16332228 (registered on Feb 3, 2016).

Dose, schedule, safety, and efficacy of guadecitabine in relapsed or refractory acute myeloid leukemia

BACKGROUND

Outcomes for patients with relapsed or refractory acute myeloid leukemia (AML) are poor. Guadecitabine, a next‐generation hypomethylating agent, could be useful in treating such patients.

METHODS

In this multicenter, open‐label, phase 2 dose‐expansion study, AML patients from 10 North American medical centers were first randomized (1:1) to receive subcutaneous guadecitabine at 60 or 90 mg/m² on 5 consecutive days in each 28‐day cycle (5‐day regimen). Subsequently, another cohort was treated for 10 days with 60 mg/m² (10‐day regimen).

RESULTS

Between June 15, 2012, and August 19, 2013, 108 patients with previously treated AML consented to enroll in the study, and 103 of these patients were treated; 5 patients did not receive the study treatment. A total of 103 patients were included in the safety and efficacy analyses (24 and 26 patients who were randomly assigned to 60 and 90 mg/m²/d, respectively [5‐day regimen] and 53 patients who were assigned to 60 mg/m²/d [10‐day regimen]). The 90 mg/m² dose showed no benefit in clinical outcomes in comparison with 60 mg/m² in the randomized cohort. Composite complete response (CRc) and complete response (CR) rates were higher with the 10‐day regimen versus the 5‐day regimen (CRc, 30.2% vs 16.0%; P = .1061; CR, 18.9% vs 8%; P = .15). Adverse events (grade ≥ 3) were mainly hematologic, with a higher incidence on the 10‐day regimen. Early all‐cause mortality was low and similar between regimens. Twenty patients (8 on the 5‐day regimen and 12 on the 10‐day regimen) were bridged to hematopoietic cell transplantation.

CONCLUSIONS

Guadecitabine has promising clinical activity and an acceptable safety profile and thus warrants further development in this population. Cancer 2018;124:325‐34. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Outcomes for patients with relapsed or refractory acute myeloid leukemia are poor. Guadecitabine, a next‐generation hypomethylating agent, has promising clinical activity and an acceptable safety profile and warrants further development in this population.

See also pages 242‐4.

Simultaneous Modeling of Biomarker and Toxicity Response Predicted Optimal Regimen of Guadecitabine (SGI-110) in Myeloid Malignancies

Guadecitabine (SGI‐110) is a novel next‐generation hypomethylating agent (HMA) administered as s.c. injection with extended decitabine exposure. Dose/exposure‐response analyses of longitudinal measures of long interspersed nucleotide element‐1 (LINE‐1) methylation and absolute neutrophil counts (ANC) pooled from 79 and 369 patients in 2 phase I/II trials, respectively, were performed to assist, through modeling and simulation, the selection of dosing regimens for phase III. Simulation of ANC predicted a decrease after a 5‐day regimen of 60 mg/m² with partial recovery before the next cycle, whereas the nadir of 90 mg/m² on the same schedule was below 100/µl. ANC following a 60 mg/m² 10‐day regimen was predicted to be suppressed below 100/µl as long as treatment continued without recovery. The developed models provided useful tools to assist simultaneous evaluation of the relative dynamics of the two effects (DNA demethylation and the effect on ANC).

Contemporary experience with high-dose interleukin-2 therapy and impact on survival in patients with metastatic melanoma and metastatic renal cell carcinoma

High-dose interleukin-2 (HD IL-2) was approved for treatment of metastatic renal cell carcinoma (mRCC) in 1992 and for metastatic melanoma (mM) in 1998, in an era predating targeted therapies and immune checkpoint inhibitors. The PROCLAIM^SM registry was established to collect and analyze data for patients treated with HD IL-2 in the current era. This analysis includes 170 patients with mM and 192 patients with mRCC treated between 2005 and 2012 with survival data current as of July 27, 2015. For patients with mM, complete response (CR) was observed in 5 %, partial response (PR) in 10 %, stable disease (SD) in 22 %, and 63 % had progressive disease (PD). The median overall survival (mOS) for these patients was 19.6 months, with a median follow-up of 43.1 months. The mOS was not reached for patients achieving CR or PR, and was 33.4 months for patients with SD. For patients with mRCC, 6 % achieved CR, 9 % had PR, 22 % had SD, and 62 % had PD. The mOS was 41 months, with a median follow-up of 46.6 months. The mOS for patients who had CR and PR was not reached and was 49.6 months for patients with SD. There were no treatment-related deaths among 362 patients. The duration of mOS for patients with mM and mRCC is longer than historically reported. These data support a continued role for IL-2 in the treatment of eligible patients with mM or mRCC and warrant further evaluation of HD IL-2 in combination or sequence with other therapeutic agents.

Abstract 2325: Immune checkpoint(s) expression in AML patients enrolled in a phase 1-2 study with guadecitabine

Immune checkpoint(s) blockade is becoming the therapeutic mainstay in melanoma and lung cancer. Based on these important clinical achievements, immunotherapy with immunomodulating monoclonal antibodies (mAb) is being explored as a new therapeutic modality in most human malignancies, either alone or in combination with other immunomodulating agents. We have provided extensive evidence that the second generation DNA hypomethylating agent (DHA), guadecitabine (SGI-110), plays a promising role in potentiating the immunogenicity and the immune recognition of human malignancies through the up-regulation of the expression of different immune molecules on cancer cells. These findings led us to hypothesize that DHA could represent ideal partners for immune checkpoint(s) blocking agents to improve their therapeutic efficacy. Here, we studied the expression of programmed death 1 (PD-1), programmed death-ligand 1 (PD-L1), and 2 (PD-L2), and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) in peripheral blood mononuclear cells of acute myeloid leukemia (AML) patients (N = 23), enrolled in a phase 1-2 study with guadecitabine. Patients included in this preliminary analysis were selected based on their responsiveness to therapy. Quantitative RT-PCR analyses showed a constitutive expression (gene/β-actin molecules &gt;7.5E-05) of PD1, PD-L1, PD-L2 and CTLA-4 in 82.6%, 100%, 47.8% and 8.7% patients, respectively. Guadecitabine therapy up-regulated (≥2 fold) the expression of PD1, PD-L1, PD-L2 and CTLA-4 in 57.9%, 56.5%, 18.2% and 0% patients, respectively, at any of the time-points investigated during treatment. De novo expression of PD1, PD-L2 and CTLA-4 was observed in 100%, 41.6% and 38.1% of the immune checkpoint(s)-negative patients, respectively.

Though preliminary, these results further support the strong link between epigenetics/DNA methylation and immune response, in cancer patients, and strengthen the therapeutic potential of epigenetic immunomodulation, with “consolidated” and emerging immune checkpoint(s) blocking mAb.

Citation Format: Carolina Fazio, Alessia Covre, Maria Lofiego, Pietro Taverna, Mohammad Azab, James N. Lowder, Sandra Coral, Michele Maio. Immune checkpoint(s) expression in AML patients enrolled in a phase 1-2 study with guadecitabine. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2325.

A Prospective Randomized Trial of Central Venous Catheter Removal Versus Intravenous Amphotericin B in Febrile Neutropenic Patients

Empiric amphotericin B therapy was compared to central venous catheter Githdrawal in a prospective randomized trial. Of 32 febrile, neutropenic patients with indwelling Broviac catheters and without documented infection, 14 had persistent fever while receiving broad spectrum antibacterial drugs. Six patients were randomized to catheter removal and eight patients received amphotericin B empirically. None of six patients responded to catheter removal and six of eight defervesced after receiving antifungal therapy (p less than 0.01). Of the six patients in whom catheters were removed, two later became afebrile while on subsequent therapy with amphotericin B. Culture and histologic evaluation of the removed catheters failed to implicate the prosthesis as an infectious source. Central venous catheters in a persistently febrile neutropenic host need not be removed, unless local difficulties or bacteremia with skin commensal organisms occur. Amphotericin B can be infused through a central venous catheter in febrile, neutropenic patients unresponsive to empiric antibacterial drugs, with many patients becoming afebrile as a result of this therapy.

Safety and tolerability of guadecitabine (SGI-110) in patients with myelodysplastic syndrome and acute myeloid leukaemia: a multicentre, randomised, dose-escalation phase 1 study

BACKGROUND

Hypomethylating agents are used to treat cancers driven by aberrant DNA methylation, but their short half-life might limit their activity, particularly in patients with less proliferative diseases. Guadecitabine (SGI-110) is a novel hypomethylating dinucleotide of decitabine and deoxyguanosine resistant to degradation by cytidine deaminase. We aimed to assess the safety and clinical activity of subcutaneously given guadecitabine in patients with acute myeloid leukaemia or myelodysplastic syndrome.

METHODS

In this multicentre, open-label, phase 1 study, patients from nine North American medical centres with myelodysplastic syndrome or acute myeloid leukaemia that was refractory to or had relapsed after standard treatment were randomly assigned (1:1) to receive subcutaneous guadecitabine, either once-daily for 5 consecutive days (daily × 5), or once-weekly for 3 weeks, in a 28-day treatment cycle. Patients were stratified by disease. A 3 + 3 dose-escalation design was used in which we treated patients with guadecitabine doses of 3-125 mg/m(2) in separate dose-escalation cohorts. A twice-weekly treatment schedule was added to the study after a protocol amendment. The primary objective was to assess safety and tolerability of guadecitabine, determine the maximum tolerated and biologically effective dose, and identify the recommended phase 2 dose of guadecitabine. Safety analyses included all patients who received at least one dose of guadecitabine. Pharmacokinetic and pharmacodynamic analyses to determine the biologically effective dose included all patients for whom samples were available. This study is registered with ClinicalTrials.gov, number NCT01261312.

FINDINGS

Between Jan 4, 2011, and April 11, 2014, we enrolled and treated 93 patients: 35 patients with acute myeloid leukaemia and nine patients with myelodysplastic syndrome in the daily × 5 dose-escalation cohorts, 28 patients with acute myeloid leukaemia and six patients with myelodysplastic syndrome in the once-weekly dose-escalation cohorts, and 11 patients with acute myeloid leukaemia and four patients with myelodysplastic syndrome in the twice-weekly dose-escalation cohorts. The most common grade 3 or higher adverse events were febrile neutropenia (38 [41%] of 93 patients), pneumonia (27 [29%] of 93 patients), thrombocytopenia (23 [25%] of 93 patients), anaemia (23 [25%] of 93 patients), and sepsis (16 [17%] of 93 patients). The most common serious adverse events were febrile neutropenia (29 [31%] of 93 patients), pneumonia (26 [28%] of 93 patients), and sepsis (16 [17%] of 93 patients). Six of the 74 patients with acute myeloid leukaemia and six of the 19 patients with myelodysplastic syndrome had a clinical response to treatment. Two dose-limiting toxicities were noted in patients with myelodysplastic syndrome at 125 mg/m(2) daily × 5, thus the maximum tolerated dose in patients with myelodysplastic syndrome was 90 mg/m(2) daily × 5. The maximum tolerated dose was not reached in patients with acute myeloid leukaemia. Potent dose-related DNA demethylation occurred on the daily × 5 regimen, reaching a plateau at 60 mg/m(2) (designated as the biologically effective dose).

INTERPRETATION

Guadecitabine given subcutaneously at 60 mg/m(2) daily × 5 is well tolerated and is clinically and biologically active in patients with myelodysplastic syndrome and acute myeloid leukaemia. Guadecitabine 60 mg/m(2) daily × 5 is the recommended phase 2 dose, and these findings warrant further phase 2 studies.

FUNDING

Astex Pharmaceuticals, Stand Up To Cancer.

High dose interleukin-2 (Aldesleukin) - expert consensus on best management practices-2014

Interleukin-2 (IL-2) was historically one of the few treatments for adults with stage IV solid tumors that could produce complete responses (CRs) that were often durable for decades without further therapy. The majority of complete responders with metastatic renal cell carcinoma (mRCC) and metastatic melanoma (mM) could probably be classified as "cures". Recent publications have suggested improved efficacy, perhaps due to improved patient selection based on a better understanding of clinical features predicting outcomes. Guidelines for clinical management were established from experience at the National Cancer Institute (NCI) and an affiliation of institutions known as the Cytokine Working Group (CWG), who were among the first to utilize HD IL-2 treatment outside of the NCI. As new centers have opened, further management variations have emerged based upon center-specific experience, to optimize administration of IL-2 and provide high quality care for patients at each individual site. Twenty years of evolution in differing environments has led to a plethora of clinical experience and effective management approaches. The goal of this review is to summarize the spectrum of HD IL-2 treatment approaches, describing various effective strategies that incorporate newer adjunctive treatments for managing the side effects of IL-2 in patients with mRCC and mM. The goal for IL-2 therapy is typically to administer the maximum number of doses of IL-2 without putting the patient at unacceptable risk for severe, irreversible toxicity. This review is based upon a consensus meeting and includes guidelines on pre-treatment screening, criteria for administration and withholding doses, and defines consensus criteria for safe administration and toxicity management. The somewhat heterogeneous best practices of 2014 will be compared and contrasted with the guidelines provided in 2001 and the package inserts from 1992 and 1998.

Implementation of an Interleukin-2 National Registry: an opportunity to improve cancer outcomes

Cancer registries have proven valuable with respect to validating therapeutic safety and drug efficacy, uncovering real-world implementation practices, and their evolution over time. Modern cancer therapeutics are approved as single agents oftentimes compared to the least active approved standard agent in randomized trials. However, the burgeoning diversity and number of drugs introduces a complexity that quickly outstrips the knowledge provided by these pivotal trials. This gap in information is particularly relevant when survival is the primary therapeutic endpoint. In addition, the inherent complexity of the immune response will make registries a particularly important tool in expeditiously understanding solid tumor immunotherapy and patient outcomes.

The Use of Registries to Improve Cancer Treatment: A National Database for Patients Treated with Interleukin-2 (IL-2)

Registries evaluating un-randomized patients have provided valuable information with respect to a therapy's utility, treatment practices, and evolution over time. While immunotherapy for cancer has been around for more than three decades, data collection in the form of a registry has not been undertaken. The authors believe that establishing a registry to study HD IL-2 immunotherapy, which has been the only systemic therapy producing long term unmaintained remissions for advanced kidney cancer and melanoma for over 20 years, will be an important resource in understanding the impact of immunotherapy with HD IL-2 in a rapidly changing therapeutic environment. Optimizing administration and improving selection of appropriate patients likely to benefit from HD IL-2 immunotherapy are two of many benefits to be derived from this endeavor.

High-dose interleukin-2 registry, PROCLAIM: Modern data on toxicities and outcomes

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Background: High dose interleukin-2 is an FDA-approved treatment for metastatic melanoma (mM) and renal cell carcinoma (mRCC) that consistently delivers durable CRs in up to 10% of patients. Concerns of treatment related toxicities are a major barrier to IL-2 administration. Nonsystematic reviews show that HD IL-2 therapy is safe, however treatment protocols have evolved to a series of best practices within over 60 HD IL-2 centers in the US. Methods: In order to capture current practices and generate modern data on toxicities and outcomes, PROCLAIM, a HD IL-2 observational database, was initiated in 2011. One goal of the registry is to survey real world HD IL-2 clinical experience used in the treatment of patients with mM, mRCC or other metastatic malignancies. A retrospective cohort was initiated for hypothesis generation and to inform the prospective cohort which has currently > 470 patients enrolled. We report here on the retrospective data comprising 267 patients (mRCC,97) treated between 2007-2012. Results: Analysis of the retrospective data show that no deaths were reported, compared to the historic mortality rate of 4% (n=255 mRCC)(Fyfe,1995). Toxicites are acute and abate rapidly after cessation of IL-2. Center-specific reasons for stopping dosing to end a cycle, as well as tolerance of elevated creatinine levels varied significantly. There were striking differences between the median number of doses administered per cycle per center, clustering around 4-6 vs. 8-14. There appears to be a trend towards higher and more durable responses with higher dose density per cycle. Conclusions: HD IL-2 can be a safe and effective immunotherapy that can be given over a short duration and delivers consistent durable therapeutic responses. The rapid resolution of its toxicities allows for its use with other therapies either in sequence or in combination; trials are currently in progress.

Anti-CD3 antibody visilizumab is not effective in patients with intravenous corticosteroid-refractory ulcerative colitis

BACKGROUND AND AIMS

Pilot studies with visilizumab, a humanised monoclonal antibody to CD3, suggest efficacy for corticosteroid-refractory ulcerative colitis (UC). A placebo-controlled trial was warranted.

METHODS

A randomised, double-blind, placebo-controlled study evaluated the efficacy of visilizumab induction treatment in 127 patients with severely active UC despite treatment with ≥5 days of intravenous corticosteroids. Patients received placebo or visilizumab 5μg/kg intravenously on days 1 and 2. Corticosteroids were tapered according to disease activity. Patients were followed up for 90 days. The primary end point was induction of response at day 45. Secondary end points included remission and mucosal healing at day 45, symptomatic response at day 15 and colectomy.

RESULTS

Response at day 45 occurred in 55% of patients receiving visilizumab compared with 47% of those who received placebo (p=0.475). Remission at day 45 occurred in 8% of patients receiving visilizumab compared with 9% of those who received placebo (p=0.704). Mucosal healing at day 45 occurred in 29% of patients receiving visilizumab compared with 26% of those who received placebo (p=0.799). Symptomatic response at day 15 occurred in 82% of patients receiving visilizumab compared with 74% of those who received placebo (p=0.244). Colectomy was performed in 18% of patients receiving visilizumab compared with 7% of those who received placebo (p=0.130). Cardiac disorders and vascular disorders occurred more frequently in the patients who received visilizumab.

CONCLUSION

Visilizumab at a dose of 5μg/kg for two consecutive days was not effective for severe, corticosteroid-refractory UC and was associated with increased cardiac and vascular adverse events. (Registered at http://www.clinicaltrials.govNCT00279422/).

Prospective randomized open-label multicenter phase I/II dose escalation trial of visilizumab (HuM291) in severe steroid-refractory ulcerative colitis

BACKGROUND

Visilizumab is a humanized IgG(2) monoclonal anti-CD3 antibody. We evaluated its safety and dose response in severe intravenous steroid-refractory ulcerative colitis (UC).

METHODS

In all, 104 patients were treated. In Stage I, 73 patients were randomly assigned to receive intravenous visilizumab 5, 7.5, 10, or 12.5 microg/kg/day for 2 consecutive days. In Stage II, 33 patients received visilizumab at the optimal clinical dose (OCD) of 5 microg/kg/day for 2 days. Symptomatic response and remission were defined by the modified Truelove-Witts severity index. Clinical response and remission were defined by the Mayo score.

RESULTS

The rates of symptomatic response at day 15 in the 5, 7.5, 10, or 12.5 microg/kg dose groups were 71%, 70%, 50%, and 61%, respectively, in Stage I and in 54% in Stage II. The symptomatic remission rates were 35%, 5%, 22%, and 11% in Stage I and 18% in Stage II. The rates of clinical response at day 30 in the 5, 7.5, 10, or 12.5 microg/kg dose groups were 71%, 65%, 50%, and 67%, respectively, in Stage I and 55% in Stage II. The clinical remission rates were 6%, 5%, 0%, and 11% in Stage I and 6% in Stage II. All patients experienced adverse events. Serious adverse events included abdominal abscess, cytomegalovirus infection, atrial fibrillation, herpes zoster, and esophageal candidiasis.

CONCLUSIONS

Treatment with visilizumab induced symptomatic response and clinical response. Results with 5 microg/kg/day were similar to those observed with higher doses.

Transient cytokine-induced liver injury following administration of the humanized anti-CD3 antibody visilizumab (HuM291) in Crohn's disease

OBJECTIVES

Monoclonal antibodies to CD3 and CD4 T-cell receptors are evolving for Crohn's disease (CD) and ulcerative colitis. Their administration is often associated with a cytokine release syndrome (CRS).

METHODS

We evaluated data from two prospective clinical trials (NCT00267709 and NCT00267722) of visilizumab (HuM291), a novel humanized anti-CD3 antibody, in 34 patients with CD who received 10 microg/kg intravenously on 2 consecutive days. Serum hepatic tests including bilirubin, alkaline phosphatase (AP), gamma-glutamyltransferase (GGT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), visilizumab concentrations, and a panel of 16 cytokines were measured pre- and postadministration of visilizumab.

RESULTS

Patients experienced CRS symptoms at a median of 45 min postinfusion. The cytokine profile was characterized by interferon-inducible protein-10 (IP-10), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma, monocyte chemotactic protein 1 (MCP-1), interleukin-8 (IL-8), interleukin-6 (IL-6), interleukin-2 (IL-2), and interleukin 1 receptor antagonist (IL-1Ra), which were elevated between 6 (IL-1Ra) and 870 (IP-10) times their baseline concentrations. TNF-alpha and IL-2 peaked at the first day 1 h post infusion, whereas all others peaked at 6 h post infusion. Eighty-six percent of patients experienced an elevation above the upper limit of normal in hepatic enzymes (GGT 73%, AST 73%, ALT 64%, and AP 42% of patients), but not bilirubin, within 6 h postinfusion.

CONCLUSIONS

Transient elevation of hepatic enzymes occurred frequently in patients with CD treated with visilizumab and was associated with CRS. CD patients could be predisposed due to an aberrant expression of adhesion molecules in the liver that promotes CRS upon engagement of the T-cell receptor and may relate to extraintestinal disease manifestations such as primary sclerosing cholangitis.

Microbial contamination of cellular products for hematolymphoid transplantation therapy: assessment of the problem and strategies to minimize the clinical impact

BACKGROUND

Hematopoietic progenitor stem cells (HPSC) are a specialized transfusion product used for transplantation. Microbial contamination may occur during harvest or subsequent manipulation of these cells. The same difficulties in ensuring a safe, sterile, final product are faced in the preparation of other cell-therapy products directly obtained from donors. Detection of contamination is problematic, and the clinical significance of infusing contaminated HPSC is controversial.

METHODS

Chimeric Therapies' manufacturing and clinical experience with BM HPSC products and validation of a culture method for detection are described. In addition, this paper reviews the literature concerning contaminated blood products, including rates and circumstances of contamination, organisms, methods of detection, and the clinical significance of infusion of contaminated products.

RESULTS

Seven of 33 BM harvest products received at Chimeric Therapies were culture positive for skin commensal organisms. Three of seven were culture positive in the infused product. This compares with literature reports of 0-42%. No patients had significant infusion reactions or evidence of infection related to the contamination.

DISCUSSION

The risks associated with microbial contamination with skin commensals are insignificant compared with other components of transplantation. Contamination with pathogens can be eliminated with careful good manufacturing practices (GMP). A series of practical recommendations are presented for the reduction of contamination in HPSC and cell-therapy products.

Lymphocyte subpopulations in healthy 1-3-day-old infants

The primary objective of this study was to establish reference ranges for the major (B, T, and natural killer; NK) and clinically relevant minor lymphocyte subsets in the peripheral blood of healthy 1-3-day-old infants and then to compare the results with those obtained in a group of healthy adults analyzed simultaneously. Forty-three infants aged 1-3 days and 38 healthy adults were recruited to the study to establish the median, 10th, and 90th percentiles of the proportions and absolute numbers of relevant lymphocyte subsets. The samples obtained from the healthy adults served as a flow cytometry process control in addition to providing a group comparator. The peripheral blood of the newborns (vs. adults) contained elevated proportions of total T cells (83% vs. 77%) and T helper cells (63% vs. 46%), with decreased proportions of T suppressor/cytotoxic cells (23% vs. 28%) and NK cells (4% vs. 10.5%). The newborns had a higher proportion (P < 0.0001) of immature B lymphocytes compared with those of adults (CD10+CD19+, 1.5% vs. 0% and CD20+CD5+, 13% vs. 6%), and the proportion of activated T cells was significantly lower (P < 0.0001; CD3+CD25+, 7.0% vs. 15%;CD3+HLA-DR+, 2.0% vs. 6% and CD8 and CD57, 0.0% vs. 8.0%). In contrast, the proportions of neonatal CD8 cells expressing CD28 (90.2% vs. 67.7%) and CD38 (96.6% vs. 70.9%) were significantly higher (P < 0.0001). The reference ranges for 1-3-day-old healthy newborns generated in this study provides a valuable tool for the assessment of immune abnormalities in very young infants.

Two-color immunofluorescence and flow cytometric analysis of peripheral blood lymphocyte subsets in Caucasian and Japanese healthy subjects

Two-color immunofluorescence using multiparameter flow cytometry was employed to examine the antigenic characteristics of peripheral blood lymphocytes in whole blood of healthy Caucasians and Japanese. The CD4/CD8 ratio in Japanese was significantly decreased compared with that in Caucasians, because of the increased number of CD8+ cells. Although the proportions of suppressor-inducer T cells (CD4+, Leu-8+) and helper-inducer T cells (naive T cells) (CD4+, CD45RA-) were low in Japanese subjects, there were no differences in the absolute numbers of suppressor-inducer T cells and helper-inducer T cells (naive T cells) in circulation. The level of activated T cells in Japanese was similar to that in Caucasians. NK cells, CD57+, CD8+ cells and CD57+, CD3+ cells were high in Japanese. Regarding B cell subsets, CD5+ B cells and activated B cells remained unchanged. However, there were slight differences in Leu-8+ B cells and Fc epsilon R+ B cells (CD20+, CD23+) between the two groups. Thus, a differing influence of racial and environmental background between healthy Caucasians and healthy Japanese on human lymphocyte subsets is present in the lymphocyte immunophenotype.

Monocytic leukemoid reaction, glucocorticoid therapy, and myelodysplastic syndrome

A leukemoid reaction is a complex and poorly understood response by the bone marrow to a variety of stresses; although any peripheral blood cell line may be involved, it is rarely a purely monocytic event. A case is reported of a true monocytic leukemoid reaction in a patient with myelodysplastic syndrome related to the effect of corticosteroids on the underlying marrow disorder.

High-dose etoposide and cyclophosphamide without bone marrow transplantation for resistant hematologic malignancy

Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.

In vitro tests that predict tumor-associated idiotype levels in the serum of patients with B cell lymphomas and leukemias

The presence of circulating tumor idiotype interferes with the in vivo effectiveness of anti-idiotype antibodies. We developed two assays that permit identification of patients with high levels of serum idiotype without the need for first producing an anti-idiotype antibody. A cell suspension made from the tumor was cultured for seven days with or without phytohemagglutin (PHA) and/or phorbol myristic acetate (PMA). Ig secretion in vitro by patients' tumor cells varied. In 4 patients, no secretion in vitro occurred, 5 patients had low levels, and 5 patients had high levels of Ig secretion. In three patients, Ig secretion occurred only after stimulation with PHA, PMA, or both. Spontaneous or induced immunoglobulin secretion in vitro is related to the levels of tumor idiotype secretion that exist in vivo. Eight patients with serum idiotype levels greater than 100 micrograms/mL (mean 265 micrograms/mL), had a minimum of 1.0 microgram/10(6) cells of idiotype secretion in vitro. Nine patients with serum idiotype levels less than 30 micrograms/mL (mean 3.7 micrograms/mL), had less than or equal to 0.5 microgram/10(6) cells of idiotype secretion in vitro. In another assay, the levels of IgM kappa and IgM lambda in patients' sera were compared with those in normal serum. An imbalance in the relative amounts of IgM kappa and IgM lambda indicated high levels of circulating idiotype in the serum, but this assay was less sensitive than the in vitro secretion assay and limited to IgM-secreting tumors. These assays will be useful for future clinical studies using anti-idiotype antibodies.

Suppression of anti-mouse immunoglobulin antibodies in subhuman primates receiving murine monoclonal antibodies against T cell antigens

Murine monoclonal antibodies stimulate the production of human anti-mouse immunoglobulin antibodies (AMIA) when administered to patients. This limits their long-term usefulness as therapeutic and diagnostic agents. We report the use of three maneuvers to suppress AMIA against T cell-specific monoclonal antibodies in cynomolgus monkeys. Twelve monkeys received daily i.v. infusions of 1 mg each of anti-Leu-2a, -3a, and -5 on days 1 through 10. One group (control) received no suppressive regimen. The second group received cyclosporine, 12.5 mg/kg daily on days -7 to +14. The third group (PI) were passively immunized with 0.4 ml of hyperimmune monkey AMIA serum on days -7, -1, 2, 4, 6, and 8. The fourth group (TLI) received 1700 rad fractionated total lymphoid irradiation ending on day -1. The animals treated with TLI were markedly delayed in the onset of AMIA, which was suppressed to less than 1% of the control group. The AMIA specific for the constant region of animals receiving PI was also suppressed to one-third of control. The majority of the AMIA in all the animals was anti-idiotypic and wholly anti-idiotypic in the TLI animals.

Suppression of anti-mouse immunoglobulin antibodies in subhuman primates receiving murine monoclonal antibodies against T cell antigens

Murine monoclonal antibodies stimulate the production of human anti-mouse immunoglobulin antibodies (AMIA) when administered to patients. This limits their long-term usefulness as therapeutic and diagnostic agents. We report the use of three maneuvers to suppress AMIA against T cell-specific monoclonal antibodies in cynomolgus monkeys. Twelve monkeys received daily i.v. infusions of 1 mg each of anti-Leu-2a, -3a, and -5 on days 1 through 10. One group (control) received no suppressive regimen. The second group received cyclosporine, 12.5 mg/kg daily on days -7 to +14. The third group (PI) were passively immunized with 0.4 ml of hyperimmune monkey AMIA serum on days -7, -1, 2, 4, 6, and 8. The fourth group (TLI) received 1700 rad fractionated total lymphoid irradiation ending on day -1. The animals treated with TLI were markedly delayed in the onset of AMIA, which was suppressed to less than 1% of the control group. The AMIA specific for the constant region of animals receiving PI was also suppressed to one-third of control. The majority of the AMIA in all the animals was anti-idiotypic and wholly anti-idiotypic in the TLI animals.

Studies on B lymphoid tumors treated with monoclonal anti-idiotype antibodies: correlation with clinical responses

Monoclonal anti-idiotype antibodies can be made which are exquisitely specific for B lymphocytic malignancies. We have conducted a clinical trial in which some patients' tumors regressed after infusion of such antibodies. Here, we evaluated characteristics of the antibodies, the tumors, and the patients to determine which features best correlated with the clinical response. Neither the isotype of the murine antibodies, nor their avidity were predictive of clinical outcome. The specific epitope to which the antibodies bound was characterized by immunochemical techniques. Reactivity with a heavy-light chain combinatorial determinant correlated somewhat with clinical effect. Variations in the characteristics of the individual tumors such as antigen sites per cell and ability to modulate the surface immunoglobulin were not predictive of response. In one patient with prolymphocytic leukemia the anti-idiotype antibody had a direct antiproliferative effect on tumor cells in vitro. This patient's tumor response was explainable by such a direct mechanism. In the other patients, who had lymphomas, therapeutic outcome correlated with the number of host nontumor cells infiltrating the tumor. The vast majority of these nontumor cells were mature T lymphocytes of the Leu 4, Leu 3 (T3, T4) phenotype. Thus, a preexistent host-tumor interaction seems to be important in the in vivo effect of anti-idiotype antibodies in B cell tumors.

Idiotype variant cell populations in patients with B cell lymphoma

Using isolated idiotype (Id) protein we generated panels of antibodies in two patients with follicular lymphoma, one of whom had never received prior chemo-or radiotherapy. Flow cytometry and frozen section tissue staining of tumor with these monoclonal antibodies (mAb) revealed multiple subpopulations within each tumor. Individual mAb stained between 7% and 83% of surface Ig+ cells in the tumor samples. These subpopulations were overlapping and no single antibody recognized all the tumor cells. However, combinations of antibodies seemed to capture total tumor in both cases. In some instances, the percentage of tumor stained by a single mAb varied over time, and differed between lymph nodes sampled at the same time. Because a single species of Id protein was used to generate mAb in each case, it appears that the antibodies were directed against idiotopes variably shared by different populations within each tumor, and this was confirmed by crossblocking studies. Tumor cells from one patient were fused to a nonsecreting heteromyeloma line K6H6/B5, and most of the resulting hybrids secreted Id protein. Four mAb were used to screen the Id proteins secreted by these hybrids, and 11 different variants (16 maximal) were found. Southern blot analysis of rearranged Ig genes was done in two hybrids and biopsy material. Identically rearranged light-chain genes were seen but it appeared as though extensive somatic variation had occurred in heavy chain genes. These studies indicate that: striking Id variation can exist at diagnosis in untreated patients, the percentage of tumor represented by an individual variant may change with time and may differ between tumor sampled from different anatomical locations, and somatic variation appears to be responsible for the observed heterogeneity. Although this degree of variation makes anti-Id antibody therapy more difficult, appropriate combinations of mAb should be more efficacious than single antibodies in such cases.

Monoclonal antibodies--therapeutic and diagnostic uses in malignancy

Murine monoclonal antibodies represent an attractive type of antitumor therapy because of their potential for exquisite specificity, production in large, pure quantities and mediation of in vivo cytotoxic effects. With maturing monoclonal antibody technology has come the use of these antibodies in clinical studies in patients with malignancy. These trials have established that monoclonal antibodies can be safely administered in large doses, that their pharmacokinetics and tissue penetration can be predicted and that in some instances a therapeutic effect can be produced by their infusion. A number of problems have also been identified by these studies, including antigenic heterogeneity of the tumor, the presence of free serum antigen, the immunogenicity of the xenogeneic antibody, modulation of the surface antigen by the antibody and a finite capacity of human effector mechanisms to mediate cytotoxicity directed by murine antibodies. Other workers are concurrently investigating the use of monoclonal antibodies in the ex vivo elimination of cells from bone marrow, as probes for serum tumor marker antigens and as carriers for radioimaging agents or toxins. Although most of these endeavors are at the earliest stages, promising preliminary results presage an important role for native and altered monoclonal antibodies in the diagnosis and treatment of malignant conditions.

Occlusion and infection in Broviac catheters during intensive cancer therapy

Before administration of intensive cytotoxic therapy, 90 central venous catheters were inserted into 80 patients with malignancies. Twenty-seven episodes of bacteremia and fungemia occurred during 96 treatment courses. The majority of these infections were due to gram-positive bacteria (45%) or fungi (22%), although gram-negative organisms accounted for 33%. Catheter occlusion occurred in patients receiving intravenous phenytoin, but blood products could be infused without difficulty. An increase in gram-positive bacteremias in patients with these catheters and drug-induced catheter occlusion must now be appreciated.

Bacteremias and fungemias in oncologic patients with central venous catheters: changing spectrum of infection

Ninety central venous catheters were inserted into 80 patients undergoing therapy for malignant neoplasms. Bacteremia and fungemia occurred in 18 of 41 treatment courses in patients with acute leukemia and in nine of 55 treatment courses in patients with solid tumors and lymphomas. Although gram-negative organisms accounted for nine (33%) cases of infection, the majority of disseminated infections were caused by gram-positive organisms (12 [45%] cases) or fungi (six [22%] cases). Central venous catheters may be helpful in the treatment of patients undergoing intensive therapy with cytotoxic agents, but the shift in-spectrum of infection to gram-positive bacteremias in patients with these catheters compared with patients treated using peripheral vein access must be appreciated.

Macular and paramacular detachment of the neurosensory retina associated with systemic diseases

We have reviewed 168 cases of angiographically proved SRD of the macular region of unknown etiology that were seen at The Cleveland Clinic Foundation. Thirty-seven percent of these patients had documented coincident systemic diseases. Of that group, patients with autoimmune disease appeared to have ocular symptoms during the active phase of the systemic illness. Nine cases are reported characterizing the coincidence of exacerbation of systemic disease with recurrent serous detachment of the neurosensory retina. It is our hypothesis that in patients with autoimmune disease, the choroiditis is secondary to the damage caused by immune complexes. Thus, in these patients, SRD was a manifestation of the systemic illness.