[CANCER RESEARCH 50. 6708-6715. October 15. 1990]
Subcutaneous Recombinant Interleukin 2 in a Dose Escalating Regimen in Patients
with Metastatic Renal Cell Adenocarcinoma1
Robert P. Whitehead,2 Dave Ward, Lucy Hemingway, George P. Hemstreet III, Edward Bradley, and
Michael Konrad
Departments of Medicine [R. P. W.] and Urology [D. W., L. H., G. P. HJ, University of Oklahoma, Oklahoma City, Oklahoma 73190, and Cetus Corporation [E. B.,
M. K.J, Emeryville, California 94608
ABSTRACT
Recombinant human interleukin 2 (rIL-2) was administered by s.c.
injection daily, 5 days/week to patients with metastatic renal cell carci
noma in an escalating dose regimen. Fifteen patients were entered in this
study and are évaluable for toxicity with one patient not évaluable for
response because of lack of measurable disease. The patient population
had a median age of 63 years with initial performance status (Southwest
Oncology Group criteria) of 0 in one patient, 1 in eight patients, and 2 in
six patients. The starting dose was 5 x 10s Cetus units/m2/day with dose
escalation to 1 x IO6, 2 x 10', 4 x IO6, and 5 x 10' Cetus units/m2/day
scheduled at 2-week intervals if no significant toxicity or response was
noted. Six patients were treated with drug doses of 2 x 10' Cetus units/
in-'/day or higher with a maximum daily dose achieved of 2 x 10' units/
nr in two patients, 4 x 10' units/m2 in two patients, and 5 x 10' units/
nr in two patients. Fatigue with decrease in performance status and
elevations in serum creatinine were the most common reasons for limiting
the dose or removing a patient from the study. Only one minor anti-
tumor response was seen.
Subcutaneously administered rIL-2 was able to alter immunological
parameters. In two of the three patients tested, development of lympho-
kine-activated killer cell activity in vivo was seen, and statistically
significant enhancement of natural killer cell activity compared to values
from a concurrently run normal control was demonstrated. With treat
ment, there was a trend toward increased numbers of circulating total
lymphocytes, OKT 8+, OKT 11+, Leu 7+, and Leu lla+ cells and
decreased numbers of circulating OKT 3+ and OKT 4+ cells. However,
for the heterogeneous group of six patients monitored, results were not
statistically significant compared to pretreatment values.
The levels of rIL-2-speciiîc antibodies were followed in the sera of 10
patients. Six of the 10 developed rIL-2-specific IgG during treatment
with five of the six patients also developing neutralizing activity.
Recombinant human interleukin 2 given by the s.c. route in the doses
and schedule used in this trial can safely be given as an outpatient
regimen with manageable toxicity. It may result in enhanced immune
function in some patients but also results in a high incidence of antibody
formation.
INTRODUCTION
Renal cell adenocarcinomas are relatively uncommon neo
plasms, making up about 3% of all malignant tumors in adults.
However, both the incidence and mortality of this tumor have
been increasing since the 1930s (1). For localized disease,
surgery for cure is the appropriate treatment. As many as one-
half of patients may already have metastatic disease at the time
of presentation, with the most common sites of métastases
being the lungs, bones, liver, and lymph nodes (1,2). Hormonal
therapy and chemotherapy are minimally effective for control
ling metastatic disease with incomplete and usually brief re-
Received2/1/89;accepted7/11/90.
The costs of publication of this article were defrayed in part by the payment
of page charges. This article must therefore be hereby marked advertisement in
accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
' This research was supported in part by funds from Cetus Corporation,
Emeryville, CA.
2 To whom requests for reprints should be addressed, at University of New
Mexico Cancer Center, 900 Camino de Salud N.E., Albuquerque, NM 87131.
sponses (3). Because of the spontaneous regressions rarely
observed in renal cell carcinoma patients and the documented
immune responses to these tumors (4), a number of immunoth-
erapeutic trials have been initiated (5). Interferons, which have
both growth inhibitory and immunomodulatory properties,
have been tested in several routes and schedules with data from
four different trials showing an overall response rate of 14% in
84 patients (6).
IL-2,3 a lymphokine produced by helper T-lymphocytes, is a
nonspecific immunopotentiator of cell-mediated immunity. In
terleukin 2 corrects the immune deficiency of nude mice in vivo
(7) and augments the generation of alloreactive cytolytic T-
lymphocytes in alloimmunized mice and NK cells in nonim-
munized mice (8). In addition, cancer patients' lymphocytes
incubated in vitro with interleukin 2 lyse fresh or cultured tumor
cells (9). Initial studies in mice demonstrated that these LAK
cells can be generated in vivo by the administration of rIL-2
and the tumor burden can be reduced in treated animals (10).
Treatment of renal cell carcinoma and melanoma patients with
high dose i.v. rIL-2 alone or rIL-2 plus LAK cells generated in
vitro has resulted in objective tumor regression (11-13). This
trial was undertaken to determine the effects of s.c. adminis
tered rIL-2 in renal cell carcinoma patients. The following
measurements were monitored: serum drug levels at various
times after treatment, serum antibody development, and deter
mination of absolute numbers of lymphocyte subsets by FACS
analysis, as well as in vitro lymphocyte lytic activity against
natural killer cell-sensitive and -resistant tumor cell lines.
MATERIALS AND METHODS
Patient Selection. Eligible patients were 18 years of age or older with
a histologically confirmed diagnosis of renal cell carcinoma and meas
urable or évaluable metastatic disease that could not be cured surgically
or with radiation therapy. Untreated patients and patients treated
previously with hormonal therapy and/or chemotherapy, radiation
therapy, or immunotherapy were eligible as long as a minimum of 3
weeks had elapsed since completion of the previous treatment and, if
necessary, there had been progression of disease outside of previous
radiation fields. Additional qualifications required for eligibility in
cluded a performance status of <2 as defined by Southwest Oncology
Group criteria (thus ambulatory >50% of the day), a WBC count of
>4000/mm3 with 21500 granulocytes/mm3, a platelet count of
>100,000/mm\ and a serum creatinine of <2.5 mg/dl, a serum aspar-
tate aminotransferase <50/IU/liter, and a total bilirubin <1.5 mg/dl.
Patients had to be fully recovered from any prior surgery, with no
evidence of severe symptomatic cardiovascular disease, i.e.. New York
Heart Association class III or IV, or serious active infections. Pregnant
or lactating women were not eligible, nor were patients with organ
allografts or symptomatic central nervous system metastasis or other
primary' neoplasm (except for skin basal cell carcinoma or surgically
3The abbreviations used are: IL-2, interleukin 2; rIL-2. recombinant human
interleukin 2; LAK, lymphokine-activated killer cell: I'llM. peripheral blood
mononuclear cell; FACS, fluorescence-activated cell sorter; NK, natural killer;
ELISA, enzyme-linked immunosorbent assay; PS, performance status.
6708
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