The trifunctional antibody catumaxomab for the treatment of malignant ascites due to epithelial cancer: Results of a prospective randomized phase II/III trial.

Abstract

Malignant ascites is a common manifestation of advanced cancers, and treatment options are limited. The trifunctional antibody catumaxomab (anti-epithelial cell-adhesion molecule x anti-CD3) represents a targeted immunotherapy for the intraperitoneal (i.p.) treatment of malignant ascites secondary to epithelial cancers. In this phase II/III trial (EudraCT 2004-000723-15; NCT00836654), cancer patients (n = 258) with recurrent symptomatic malignant ascites resistant to conventional chemotherapy were randomized to paracentesis plus catumaxomab (catumaxomab) or paracentesis alone (control) and stratified by cancer type (129 ovarian and 129 nonovarian). Catumaxomab was administered as an i.p. infusion on Days 0, 3, 7 and 10 at doses of 10, 20, 50 and 150 mug, respectively. The primary efficacy endpoint was puncture-free survival. Secondary efficacy parameters included time to next paracentesis, ascites signs and symptoms and overall survival (OS). Puncture-free survival was significantly longer in the catumaxomab group (median 46 days) than the control group (median 11 days) (hazard ratio = 0.254: p < 0.0001) as was median time to next paracentesis (77 versus 13 days; p < 0.0001). In addition, catumaxomab patients had fewer signs and symptoms of ascites than control patients. OS showed a positive trend for the catumaxomab group and, in a prospectively planned analysis, was significantly prolonged in patients with gastric cancer (n = 66; 71 versus 44 days; p = 0.0313). Although adverse events associated with catumaxomab were frequent, they were manageable, generally reversible and mainly related to its immunologic mode of action. Catumaxomab showed a clear clinical benefit in patients with malignant ascites secondary to epithelial cancers, especially gastric cancer, with an acceptable safety profile.

Full text

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The trifunctional antibody catumaxomab for the treatment of
malignant ascites due to epithelial cancer: results of a
prospective randomized phase II/III trial
Markus M. Heiss1, Pawel Murawa2, Piotr Koralewski3, Elzbieta Kutarska4, Olena O. Kolesnik5, Vladimir V. Ivanchenko6,
Alexander S. Dudnichenko7, Birute Aleknaviciene8, Arturas Razbadauskas9, Martin Gore10, Elena Ganea-Motan11,
Tudor Ciuleanu12, Pauline Wimberger13, Alexander Schmittel14, Barbara Schmalfeldt15, Alexander Burges16,
Carsten Bokemeyer17, Horst Lindhofer18, Angelika Lahr19and Simon L. Parsons20
1Department of Surgery, Cologne-Merheim Medical Center, University of Witten-Herdecke, Cologne, Germany
2Department of Oncological Surgery, Wielkoposka Cancer Center, Poznan, Poland
3Department of Chemotherapy, Rydygier Memorial Hospital, Krakow, Poland
4Department of Oncological Gynecology, Center of Oncology of Lublin, Lublin, Poland
5Institute of Oncology, Academy of Medical Science of Ukraine, Kiev, Ukraine
6Regional Clinical Oncology Dispensary, Velikiy Novgorod, Russia
7Department of Oncology and Pediatric Oncology, Kharkov Medical Academy of Postgraduate Education, Kharkov, Ukraine
8Institute of Oncology, Vilnius University, Vilnius, Lithuania
9Department of Surgery, Klaipeda Seamen’s Hospital, Klaipeda, Lithuania
10Medical Oncology and Drug Development, Royal Marsden Hospital, London, United Kingdom
11Department of Oncology, Spitalul Judetean de Urgenta ‘Sf Ioan cel Nou’, Suceava, Romania
12Department of Medical Oncology, Cancer Institute Ion Chiricuta, Cluj-Napoca, Romania
13Department for Obstetrics and Gynecology, University of Duisburg-Essen, Essen, Germany
14Department of Hematology, Oncology and Transfusion Medicine, Charite ´, University Hospital Berlin, Berlin, Germany
15Department for Obstetrics and Gynecology, Technical University Munich, Munich, Germany
16Department of Obstetrics and Gynecology, University Hospital Grosshadern, Munich, Germany
17Department of Internal Medicine II (Hematology, Oncology), University Hospital Eppendorf, Hamburg, Germany
18TRION Pharma GmbH, Munich, Germany
19Fresenius Biotech GmbH, Munich, Germany
20Department of Surgery, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
Key words: catumaxomab, trifunctional antibody, malignant ascites, epithelial cancer, clinical trial
Abbreviations: ANCOVA: analysis of covariance; C þ P: catumaxomab plus paracentesis; CI: confidence interval; CT: computed
tomography; EpCAM: epithelial cell-adhesion molecule; HAMA: human anti-mouse antibody; HR: hazard ratio; i.p.: intraperitoneal; ITT:
intent-to-treat; OS: overall survival; P: paracentesis alone; TNF: tumor necrosis factor
All the authors participated in the study and reviewed and approved the manuscript. Markus Heiss was the coordinating investigator for
Germany, Simon Parsons was the coordinating investigator for the other countries and Angelika Lahr was the Global Clinical Project
Director.
Conflict of interest: Markus Heiss has served as a consultant for Fresenius Biotech GmbH and TRION Pharma GmbH. Simon Parsons has
served as a consultant and advisory board member for Fresenius Biotech GmbH and received funding for a research fellow. Carsten
Bokemeyer has served as a consultant and advisory board member for Fresenius Biotech GmbH. Pauline Wimberger received honoraria for
presentations, research funding for other clinical trials with catumaxomab and other remuneration from Fresenius Biotech GmbH. Horst
Lindhofer is the inventor and patent holder for catumaxomab and the chief executive officer of TRION Pharma GmbH. Angelika Lahr is an
employee of Fresenius Biotech GmbH.
Grant sponsor: Fresenius Biotech GmbH
DOI: 10.1002/ijc.25423
History: Received 23 Dec 2009; Accepted 23 Mar 2010; Online 27 Apr 2010
Correspondence to: Markus M. Heiss, Department of Abdominal, Vascular and Transplantation Surgery, Cologne-Merheim Medical Center,
Chair for Surgery, University Witten/Herdecke, Ostmerheimer Str. 200, D-51109 Cologne, Germany, Fax: þ49-221-8907-8561, E-mail:
heissm@kliniken-koeln.de
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International Journal of Cancer
IJC

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Malignant ascites is a common manifestation of advanced cancers, and treatment options are limited. The trifunctional
antibody catumaxomab (anti-epithelial cell-adhesion molecule x anti-CD3) represents a targeted immunotherapy for the
intraperitoneal (i.p.) treatment of malignant ascites secondary to epithelial cancers. In this phase II/III trial (EudraCT
2004-000723-15; NCT00836654), cancer patients (n 5 258) with recurrent symptomatic malignant ascites resistant to
conventional chemotherapy were randomized to paracentesis plus catumaxomab (catumaxomab) or paracentesis alone
(control) and stratified by cancer type (129 ovarian and 129 nonovarian). Catumaxomab was administered as an i.p. infusion
on Days 0, 3, 7 and 10 at doses of 10, 20, 50 and 150 lg, respectively. The primary efficacy endpoint was puncture-free
survival. Secondary efficacy parameters included time to next paracentesis, ascites signs and symptoms and overall survival (OS).
Puncture-free survival was significantly longer in the catumaxomab group (median 46 days) than the control group (median 11
days) (hazard ratio 5 0.254: p < 0.0001) as was median time to next paracentesis (77 versus 13 days; p < 0.0001). In addition,
catumaxomab patients had fewer signs and symptoms of ascites than control patients. OS showed a positive trend for the
catumaxomab group and, in a prospectively planned analysis, was significantly prolonged in patients with gastric cancer (n 5 66;
71 versus 44 days; p 5 0.0313). Although adverse events associated with catumaxomab were frequent, they were manageable,
generally reversible and mainly related to its immunologic mode of action. Catumaxomab showed a clear clinical benefit in
patients with malignant ascites secondary to epithelial cancers, especially gastric cancer, with an acceptable safety profile.
Malignant ascites results from the accumulation of fluid
within the peritoneal cavity caused by the intraperitoneal
(i.p.) spread of tumor cells1–3and can be caused by a number
of different cancers including ovarian, gastric, endometrial,
breast, colon and pancreatic.3The mechanisms leading to
malignant ascites are independent of the primary tumor.
While infiltrating the peritoneum, tumor cells interfere with
the regulation of fluid flow in the peritoneal cavity. Because
of an imbalance between efflux and influx, several liters of
fluid can accumulate.4Ascites results in poor quality of life
because of burdensome symptoms such as abdominal swel-
ling, a permanent feeling of fullness, pain, nausea, dyspnea,
insomnia and fatigue.1,5–7Malignant ascites is a manifestation
of advanced disease and is associated with a poor progno-
sis.3,8,9Although chemotherapy is the usual first-line treat-
ment for patients presenting with ascites,9there is a lack of
evidence for its efficacy in patients with recurrent ascites
from randomized trials. Intraperitoneal administration of
radioisotopes or chemotherapy and peritoneovenous shunting
procedures have also been used, but the data are limited.10,11
Paracentesis is the most common treatment for the relief of
symptoms of recurrent ascites.10,11However, repeated para-
centesis leads to frequent hospital admission and is associated
with several problems, including pain because of the proce-
dure, protein loss causing hypovolemia and a risk of infec-
tion, peritonitis and bowel perforation. Furthermore, because
paracentesis only provides short-term symptom relief, it has
to be repeated frequently, often once a week.
Catumaxomab is a trifunctional monoclonal antibody with
two different antigen-binding sites and a functional Fc do-
main.12The two specific antigen-binding sites bind to epithe-
lial tumor cells via the epithelial cell-adhesion molecule
(EpCAM) and to T-cells via CD3. Furthermore, catumaxo-
mab activates Fcc-receptor I-, IIa- and III-positive accessory
cells via its functional Fc domain.13
recruitment and activation of different immune effector cells
at the tumor site leads to improved tumor-cell elimination by
The simultaneous
different immunologic killing mechanisms.14
expressed in the majority of epithelial cancers, making it an
attractive target for antibody therapy.15Tumor cells in malig-
nant effusions have been shown to express EpCAM in 70–
100% of those cases that commonly cause malignant ascites,
e.g., breast, ovarian, gastric and colorectal cancer.16–18EpCAM
is also expressed on cells of normal epithelial tissues.15How-
ever, normal EpCAM-positive tissue is assumed to be inacces-
sible to intact antibodies in vivo because of its protection by
the basal lamina.19In contrast, EpCAM in solid tumors is
expected to be accessible for binding with intact antibodies
after passage through the leaky tumor mosaic vessels or in
body fluids such as ascites or pleural effusions. Furthermore,
the peritoneal cavity is lined by mesothelial cells that do not
express EpCAM.20Therefore, the i.p. administration of catu-
maxomab offers the advantage of a targeted, locoregional
immunotherapy against EpCAMþ tumor cells in the perito-
neal cavity, which are the main cause of malignant ascites.
In previous studies, catumaxomab has demonstrated effi-
cacy in patients with malignant ascites with an acceptable
safety profile.21,22This study is the first prospective, random-
ized trial designed to compare the i.p. infusion of catumaxo-
mab plus paracentesis (C þ P) with paracentesis alone to
assess the efficacy and safety of catumaxomab in the treat-
ment of malignant ascites due to epithelial cancers.
EpCAM is
Material and Methods
Study design
This was a two-arm, randomized, open-label, phase II/III study
in patients with symptomatic malignant ascites secondary to
epithelial cancers requiring symptomatic therapeutic paracente-
sis (Fig. 1). The study (EudraCT number: 2004-000723-15;
ClinicalTrials.gov identifier: NCT00836654) was approved by
an independent ethics committee at each study center, and all
patients gave written informed consent before participation.
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The study was conducted in compliance with Good Clinical
Practice guidelines and the Declaration of Helsinki.
Treatment
After draining the ascites fluid, 500 mL of 0.9% sodium chlo-
ride solution was administered by i.p. infusion before each
catumaxomab dose to support intra-abdominal distribution
of the antibody. Based on the dose, catumaxomab was predi-
luted in an appropriate volume of 0.9% sodium chloride solu-
tion placed in a 50-mL perfusor syringe. Catumaxomab was
administered as four 6-hr constant-rate i.p. infusions at doses
of 10, 20, 50 and 150 lg on Days 0, 3, 7 and 10, respectively,
via an i.p. catheter in parallel with an infusion of 250 mL of
0.9% sodium chloride solution. All catumaxomab i.p. infu-
sions were performed in an inpatient setting. The dosing and
administration regimen was based on the results of a phase
I/II study.22The catheter remained in the peritoneal cavity for
all four infusions and was removed 1 day after the last infu-
sion. Before each catumaxomab infusion and 1 day after the
last infusion, the remaining fluid was drained from the
Figure 1. (a) Study design. (b) CONSORT flow diagram (only results for the intent-to-treat and safety populations are included in this
article). *The main cancer types in the nonovarian stratum were gastric (n ¼ 66, 51%), breast (n ¼ 13, 10%), pancreas (n ¼ 9, 7%), colon
(n ¼ 8, 6%) and endometrial (n ¼ 6, 5%).
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peritoneal cavity via the catheter. The control group was
treated with one therapeutic paracentesis only (Day 0).
In both groups, repuncture was performed if patients
required relief of ascites symptoms. Investigators had a clear
algorithm to determine when a therapeutic paracentesis
should be performed. (i) Ascites volume >1 L based on a
computed tomography (CT) scan was estimated by the local
radiologist. This was retrospectively confirmed by two inde-
pendent blinded readers and was supported by objective
measurements of collected ascites volume and changes in
body weight. The collected ascites volume was recorded and
plotted against time to determine the in vivo accumulation
rate. (ii) Symptomatic ascites based on signs (physical exami-
nation) and symptoms (ascites-specific patient questionnaire)
was assessed by the investigator.
Patients were assessed with up to five follow-up visits at 8
days and 1, 3, 5 and 7 months (end of study) after the last
infusion (catumaxomab group) or therapeutic paracentesis
(Day 0, control group). In the control group, the end of the
study was reached when the patient required the next para-
centesis or died, whichever occurred first. For the analysis of
the primary endpoint, any patients lost to follow-up were
censored at the time of their last visit. After reaching the pri-
mary endpoint, all patients were further assessed every 2
months until death or 6 months after the last patient was
randomized, whichever was later, for the evaluation of overall
survival (OS). Patients in the control group who fulfilled the
eligibility criteria and had two therapeutic punctures after
Day 0 were permitted to receive catumaxomab in a subse-
quent, single-arm, crossover period (data not shown).
Endpoints
The primary efficacy endpoint was puncture-free survival.
This composite endpoint was defined as the time to first
need for therapeutic puncture or death after treatment,
whichever occurred first. Secondary efficacy parameters
included time to next paracentesis, ascites signs and symp-
toms and OS. Ascites symptoms (anorexia, nausea, early sati-
ety, vomiting, abdominal pain, abdominal swelling, dyspnea,
fatigue, swollen ankles and heartburn) were assessed subjec-
tively using a patient questionnaire with a four-point Likert
scale (none, mild, moderate and severe).23Ascites signs
(abdominal distension dull to percussion, shifting dullness,
fluid thrill and bulging flanks) were assessed objectively after
abdominal examination by the investigator. The investigator
also determined whether or not the ascites was symptomatic
based on an assessment of the results of the patient question-
naire and the abdominal examination. For the final assess-
ment of OS, the results of the poststudy period (i.e., the
period after the primary endpoint was reached) were included.
Safety was assessed by adverse event reporting throughout
the study. Adverse events were coded according to the Medi-
cal Dictionary for Regulatory Activities version 8.0. Adverse
events were graded according to the National Cancer Insti-
tute Common Toxicity Criteria (version 2.0, April 30, 1999).
Patients
Adult patients aged ?18 years with histologically confirmed
epithelial cancer and EpCAMþ tumor cells in the ascites
fluid were eligible for inclusion in this study. Other inclusion
criteria were as follows: Karnofsky performance status ?60;
life expectancy >8 weeks; estimated ascites volume >1 L by
CT scan; at least one symptomatic paracentesis within 5 weeks
as well as an objectively verified, clinical need for a second
paracentesis and refractory or resistant to chemotherapy or
standard chemotherapy was no longer feasible. Patients were
excluded if they had: exposure to cancer chemotherapy or
radiotherapy within the previous 28 days; previous treatment
with murine monoclonal antibodies; enteral feeding at study
entry or ileus within the previous 30 days and >70% tumor
infiltration of the liver, or portal vein obstruction, or throm-
bosis. Patients were randomized 2:1 to paracentesis plus catu-
maxomab or paracentesis alone (control) and stratified by
cancer type (ovarian and nonovarian).
Determination of tumor-cell load
Tumor-cell load (number of EpCAMþ tumor cells/106ascites
cells) in ascites fluid was analyzed for both groups at screen-
ing and at puncture visit. In addition, measurements were
performed in the catumaxomab group during treatment
before the second infusion and 1 day after the last infusion.
Tumor-cellloadwasdetermined
EpCAMþ tumor cells in ascites fluid/peritoneal lavage and
was performed using immunocytochemistry as described else-
where.21Briefly, ascites cells were harvested by centrifugation
or ficoll density centrifugation. A constant number of cells
was centrifuged on cytospin slides, and tumor cells were
labeled at screening (before therapy) with the anti-EpCAM
antibody HO-3 (the parental antibody of catumaxomab;
TRION Pharma, Munich, Germany), ensuring that the
patients’ EpCAMþ tumor cells could be recognized by catu-
maxomab. To prevent inhibition of antibody staining by catu-
maxomab residuals in ascites samples during and after ther-
apy, these samples were stained with the anti-EpCAM
antibody VU1D9 (TRION Research, Martinsried, Germany),
which recognizes a different EpCAM epitope to HO-3/catu-
maxomab. HO-3 and VU1D9 were both directly labeled with
a Texas Red fluorescence dye. All cytospins were analyzed by
a computerized image analysis system (MDSTM; Applied Imag-
ing International, Newcastle upon Tyne, UK) to count the cells
labeled with Texas Red. Leukocytes were stained with an anti-
CD45 antibody (Caltag Laboratories, Hamburg, Germany) and
its corresponding secondary antibody IgG1 Alexa Fluor 488
(Molecular Probes, Invitrogen, Karlsruhe, Germany).
viaquantificationof
Detection of antidrug antibodies
As catumaxomab is a nonhumanized mouse/rat antibody, the
development of human anti-mouse antibodies (HAMAs)
against catumaxomab was investigated. HAMAs were ana-
lyzed in serum samples at the following timepoints: at
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screening, before the third infusion, before the fourth infu-
sion, 8 days and 1 month after the last infusion and at punc-
ture visit. A commercially available in vitro diagnostic test,
HAMA-ELISA Medac (Medac, Hamburg, Germany), a sim-
ple and rapid one-step enzyme immunoassay for the quanti-
tative determination of HAMAs in serum, was used. The test
was performed according to the manufacturer’s instructions
and calibrated against goat anti-mouse IgG antibodies, with a
measuring range of 40–2,000 ng/mL. Briefly, microtiter plates
were coated with mouse IgG and then clinical-trial samples
and peroxidase-labeled mouse IgG (conjugate) were added.
For detection of bound HAMAs, a tetramethylbenzidine sub-
strate was added. The reaction was stopped by the addition
of sulfuric acid. The absorption of the colored product was
measured photometrically at 450 nm (reference wavelength:
620–650 nm). An internal test to detect HAMAs and human
anti-rat antibodies showed a significant correlation with the
results of the Medac test.
Statistics
The planned sample size of 216 randomized patients was
based on the following considerations: the primary efficacy
variable (puncture-free survival), the duration of patient ob-
servation (7 months [30 weeks]), the median time to end of
puncture-free survival (twice the time in the catumaxomab
group than in the control group: the assumed median punc-
ture-free survival time was 5 weeks in the control group versus
10 weeks in the catumaxomab group), 10% of patients lost to
follow-up, alpha level 0.05, two-sided, no adjustment for the
two tests (ovarian and nonovarian subgroups) and a random-
ization ratio of 2:1 (catumaxomab versus control group).
All statistical tests were two-sided, and the level of signifi-
cance was 5%. The evaluation of puncture-free survival in the
intent-to-treat (ITT) population (all randomized patients)
was the primary efficacy analysis. The log-rank test and the
hazard ratio (HR) were used to compare puncture-free sur-
vival between the two treatment groups. The variables to
define the need for paracentesis were analyzed by chi-square
test, kappa coefficients, McNemar’s test and analysis of covar-
iance (ANCOVA), as appropriate. Secondary variables were
analyzed with Kaplan-Meier estimates, log-rank test, HR, chi-
square test, Cox regression analysis, Cochran-Mantel-Haens-
zel test, ANCOVA or Wilcoxon test, as appropriate. Statisti-
cal testing for secondary variables was descriptive only. The
safety population consisted of all patients who received at
least one dose of catumaxomab or were randomized to the
control group. Data were analyzed separately for patients
with ovarian and nonovarian cancer with an additional anal-
ysis of the pooled population and a subgroup population of
the nonovarian cancer patients with gastric cancer (the larg-
est patient subgroup in the nonovarian cancer stratum).
Results
From September 2004 to August 2006, 258 patients were
randomized at 75 centers in 13 countries (ITT population):
85 to paracentesis plus catumaxomab (catumaxomab) and 44
to paracentesis alone (control) in both disease strata (129
ovarian and 129 nonovarian cancer) (Fig. 1). The main can-
cer types in the nonovarian stratum were gastric (n ¼ 66,
51%), breast (n ¼ 13, 10%), pancreas (n ¼ 9, 7%), colon
(n ¼ 8, 6%) and endometrial (n ¼ 6, 5%). Thirteen patients
in the catumaxomab group (five ovarian and eight nonovarian
cancer) were not treated and were withdrawn from the study,
but were included in the ITT population. The reasons for not
receiving catumaxomab treatment were withdrawal of con-
sent (n ¼ 5), death before treatment could be started (n ¼ 4)
and other (n ¼ 4), which included a serious adverse event,
ileus, failure to meet inclusion criteria and problems with
Table 1. Demographic and clinical characteristics at baseline (intent-to-treat population)
Characteristic
Ovarian cancer (n 5 129)Nonovarian cancer (n 5 129)
Catumaxomab plus
paracentesis (n 5 85)
Paracentesis
alone (n 5 44)
Catumaxomab plus
paracentesis (n 5 85)
Paracentesis
alone (n 5 44)
Median age, years (range) 59 (23–85)57 (41–82) 57 (31–86)60.5 (31–85)
Median BMI, kg/m2(SD)23.9 (13.9–47.5)24.5 (17.3–34.6)21.6 (15–39.6) 22.1 (16.2–39.5)
Median time since diagnosis of
primary tumor, months (range)
19.0 (0–188) 23.5 (0–102)11.0 (0–229) 11.0 (0–343)
Median time since first diagnosis of
ascites, months (range)
7.0 (0–62)6.5 (0–82) 2.0 (0–76)2.0 (0–58)
Median number of ascites
drainages (range)
1 (1–10)1 (1–9)1 (1–9) 1 (1–10)
Median time since last therapeutic
ascites puncture, days (range)
17 (1–46)20 (3–36)14 (2–63)17.5 (2–35)
Median number of previous
chemotherapies (range)
3 (0–8)3 (1–10)1 (0–10)1 (0–9)
Median ascites volume at screening,
mL (range)
2,927 (80–12,683)2,927 (98–7,000)3,763 (130–11,473)3,951 (355–14,000)
Karnofsky index 80–90, n (%)45 (53)32 (73)47 (56)19 (43)
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