Axel Schomburg

Chemoimmunotherapy of advanced malignant melanoma: sequential administration of subcutaneous interleukin-2 and interferon-α after intravenous dacarbazine and carboplatin or intravenous dacarbazine, cisplatin, carmustine and tamoxifen

Both chemotherapy and interleukin-2 and/or interferon-alpha produce objective responses in a proportion of advanced malignant melanoma patients. While duration of response to chemotherapy is short, i.e. usually below 4 months, immunotherapy has resulted in a small number of long-lasting remissions in patients with metastatic melanoma. In two consecutive phase II trials in a total of 67 patients, we assessed the potential synergism between both modalities, i.e. chemo- and immunotherapy. Treatment consisted of intravenous (i.v.) carboplatin (CBDCA, 400 mg/m2) and dacarbazine (DTIC, 750 mg/m2) given twice (i.v. bolus over 30 min) at 3-week intervals, or 4 cycles of DTIC (220 mg/m2 i.v. 3 days), cisplatin (DDP, 35 mg/m2 i.v. 3 days), carmustine (BCNU, 150 mg/m2 i.v. cycles 1 and 3) and tamoxifen (TAM, 20 mg oral/daily) at 3-week intervals. Chemotherapy was followed by immunotherapy with combined subcutaneous (s.c.) interleukin-2 (rIL-2) and SC interferon-alpha 2 (rIFN-alpha). Among 40 patients who received a full cycle of chemotherapy with CBDCA/DTIC and sequential immunotherapy, there were 3 (7.5%) complete remissions (CRs) with a median duration of 19 months (range 13-26+). Partial remissions (PRs) were noted in 11 (27.5%) patients with a median response duration of 8 (range 5-14) months. Among 27 patients who received DTIC/DDP/BCNU/TAM and rIL-2/rIFN-alpha, there were 3 (11%) complete remissions and 12 (44.5%) partial remissions. Duration of complete and partial remissions ranged from 9+ to 13+ (median, 11+), and 5 to 15+ (median, 7+) months, respectively. Chemotherapy produced mostly moderate toxicity. Thrombocytopenia was common with the nadir after a median time of 18 days following start of CBDCA/DTIC and DTIC/DDP/BCNU, respectively. 10 patients required transfusion of thrombocytes. Nausea and vomiting due to chemotherapy were well tolerated using concomitant ondansetrone (8 mg i.v.). Immunotherapy was self-administered at home with mild to moderate side effects; malaise, fever, chills, nausea/vomiting, diarrhoea, anorexia and arthralgias were most frequent, but were spontaneously reversible after ending rIL-2/IFN-alpha. A mean 87 and 88% of the projected doses of rIL-2 and rIFN-alpha were administered on either protocol. There were no life-threatening complications and no treatment-related deaths. The sequential combination of chemotherapy and rIL-2 plus rIFN-alpha had at least additive therapeutic activity against metastatic malignant melanoma. The schedules produced long-lasting remissions and were tolerated well overall. These trials substantiate a potential role for low to intermediate dose immunotherapy in maintaining and consolidating therapeutic effects of chemotherapy in metastatic melanoma.

Expansion of Peripheral Blood Natural Killer Cells Correlates with Clinical Outcome in Cancer Patients Receiving Recombinant Subcutaneous lnterleukin-2 and Interferon-α-2

Natural killer (NK) cells are believed to contribute to the clinical efficacy of cancer immunotherapy using recombinant interleukin-2 (rIL-2) in humans. In previous trials of high-dose i.v. rIL-2, however, no correlation has been established between circulating NK cells and treatment response. Between January 1989 and October 1990, we treated a total of 47 outpatients with advanced tumors using low-dose s.c. rIL-2 and interferon-alpha-2 (rIFN-alpha). Therapy consisted of a 2-day rIL-2 pulse at 18 million IU/m2/day, followed by 6 weeks of rIL-2 (3.6 x 10(6)-4.8 x 10(6) IU/m2/day x 5 days/week) and rIFN-alpha (5 x 10(6)-6 x 10(6) U/m2 x 3/week). Before and after therapy, we phenotypically evaluated circulating lymphocytes and correlated them with clinical response. During 6-week therapy, peripheral blood lymphocytes bearing the CD56 (NK-cell-associated) surface antigen were increased significantly (p < or = 0.005) in treatment responders [complete response (CR) and partial response (PR), n = 10; 3.8-fold] and stable disease (SD) patients (n = 20; 2.1-fold), while patients with progressive disease (PD, n = 17) exhibited no significant expansion of circulating NK cells (p > 0.1). After one 6-week treatment cycle, CR/PR patients had significantly more peripheral NK cells, when compared with patients in SD (1.6-fold) and PD (1.9-fold) (p < 0.04). The overall number of circulating lymphocytes was also increased upon therapy (1.6-fold; p < or = 0.001), but remained independent of response (p > 0.4). These data demonstrate that s.c. rIL-2 and s.c. rIFN-alpha produce a significant increase in peripheral blood NK cells; this expansion correlates significantly with treatment response in advanced tumor patients receiving long-term combination immunotherapy at outpatient doses.

Renal, metabolic, and hemodynamic side-effects of interleukin-2 and/or interferonα: Evidence of a risk/benefit advantage of subcutaneous therapy

Systemic immunotherapy with recombinant interleukin-2 (rIL-2) via intravenous (i.v.) and subcutaneous (s.c.) administration produces objective responses in a proportion of advanced cancer patients. While most of the previous investigations chose the i.v. route for cytokine application, there is an increasing number of trials employing s.c. rII-2 therapy. The comparison of reported response rates for i.v. versus s.c. therapy reveals no significant differences between these modalities. In an effort to describe systemic toxicities of s.c. cytokine therapy with regard to renal, metabolic, and hemodynamic abnormalities and to compare these effects to toxicities reported upon i.v. therapy, we retrospectively evaluated 148 treatment cycles of s.c. immunotherapy given to 107 outpatients. Our study cohorts consisted of 15 patients who received s.c. rIL-2 at doses of (4.8–14.4)×106 IU m−2 day1 5 days/week for a total of 8 weeks, 20 patients who received rIFNα2b at (3.0–6.0)×106 m−2 day−1 thrice weekly for a total of 6 weeks, and 72 patients who were given s.c. rILFNα2b at 6.0×106 U/m2, three times per week, plus s.c. rIL-2 at (14.4–18.0)×106 IU/m2 on days 1 and 2, followed by 4.8×106 IU m−2 day−1 5 days/week for 6 consecutive weeks. These treatment regimens were well tolerated in the outpatient setting; no toxic death occurred, and none of the patients developed life-threatening toxicity due to a capillary leak syndrome. Upon s.c. combination therapy, dyspnea at rest occurred in 6% of patients and grade III and IV hypotension occurred in 7% and 4%, respectively; plasma protein was significantly decreased (mean nadir±standard deviation, 67±5 g/l). In addition, s.c. therapy led to a significant increase in serum creatinine (mean peak±standard deviation, 115.1±21.4 μmol/l) and urea nitrogen (mean peak±standard deviation, 6.5±2.5 mmol/l); electrolyte disturbances and direct nephrotoxicity never caused major clinical symptoms. This was in marked contrast to a multitude of dose-limiting and life-threatening adverse reactions reported upon i.v. rIL-2 therapy. We conclude that palliative low to intermediate-dose s.c. rIL-2/rIFNα combination therapy, in contrast to i.v. treatment, can be administered in the ambulatory setting with good practicability and excellent safety. This outpatient regimen is as effective against metastatic renal cell cancer as the most aggressive i.v. rIL-2 protocol reported.

Lack of therapeutic efficacy of tamoxifen in advanced renal cell carcinoma.

In the present study, we treated a total of 62 patients with advanced renal cell carcinoma with high-dose tamoxifen (100 mg/m2/day). Patients were treated in the outpatient setting, and were evaluated 8-12 weeks after initiation of therapy or sooner, when clinical disease progression was evident; a total of 15 patients were seen at short regular intervals for evaluation of clinical and laboratory parameters. Of these 62 patients, 59 were evaluable for treatment response, survival and systemic toxicity. One partial remission was achieved (1.7%; 95% confidence interval, 0.04-9.09%), response duration was 3 months. 10 patients presented with stable disease, for a median duration of 4.0 months, and 48 patients exhibited disease progression upon and after therapy. Systemic toxicity was significant; severe fatigue occurred in 5% of patients, and moderate anaemia, dyspnea, alopecia and malaise in almost 20% of patients. Antineoplastic efficacy of tamoxifen at this dosage in this cohort of patients was at best marginal and well in the range associated with the occurrence of spontaneous remissions. Toxicity was substantial, and it was not balanced by therapeutic benefit. This is consistent with the known lack of therapeutic efficacy of endocrine therapy in advanced renal cell carcinoma.

Low-Dose lnterleukin-2 in Combination with Interferon-α Effectively Modulates Biological Response in vivo

Phenotypic characterization of peripheral blood lymphocytes was performed in patients with advanced metastatic cancer receiving low-dose recombinant interleukin-2 (rIL-2) and recombinant interferon-α

Treatment of Metastatic Colorectal Cancer Patients with 5-Fluorouracil in Combination with Recombinant Subcutaneous Human lnterleukin-2 and Alpha-lnterferon

We treated 14 patients with progressive metastatic colorectal cancer, using a combination of subcutaneous recombinant human interleukin-2 (4.8 x 10(6) IU/m2 three times daily on days 1 and 22, and twice daily on days 2 and 23, followed by 2.4 x 10(6) IU/m2 twice daily on days 3-5, 8-12, 24-26, and on 5 consecutive days per week, starting day 29), recombinant human interferon-alpha 2a (5.0 x 10(6) U/m2 thrice weekly), and 5-fluorouracil (750 mg/m2 i.v. bolus on days 15-19, and at weekly intervals thereafter, with a 1-week off-therapy interval every 4 weeks). Therapy was continued until disease progression occurred. Four (29%) and 8 (57%) evaluable patients achieved partial remission and stable disease, respectively; median response duration was 5.9 months. Toxicity of this regimen was moderate; the most common side effects were thrombocytopenia, leukopenia, nausea/vomiting, anorexia, malaise and fevers in all patients, along with diarrhea (63%) and mucositis (54%). Less than 10% of patients developed WHO grade IV toxicity; no toxic deaths occurred. Efficacy of this combination was not substantially different from alternative 5-fluorouracil-based regimens.

Hematotoxicity of lnterleukin-2 in Man: Clinical Effects and Comparison of Various Treatment Regimens

BACKGROUND Immunotherapy using recombinant human interleukin-2 (rIL-2) produces objective responses in a proportion of advanced cancer patients. While early investigators employed intravenous (i.v.) treatment regimens, recent clinical trials applied therapy schedules via subcutaneous (s.c.) injection, mostly in combination with recombinant human interferon-alpha (rIFN-alpha). There were no significant differences in reported response rates between i.v. and s.c. treatment regimens. METHODS We retrospectively evaluated 148 treatment cycles of s.c. immunotherapy administered to 107 outpatients. Adverse effects of s.c. cytokine therapy were described with regard to hematotoxicity, and compared to adverse effects reported upon high- or intermediate-dose i.v. rIL-2 therapy. Our study population consisted of 15 patients who received s.c. rIL-2 at doses of 4.8-14.4 million IU/m2/day on 5 days per week, 20 patients who were treated with rIFN-alpha 2b at 3.0-6.0 million U/m2/day thrice weekly, and 72 patients who were given s.c. rIFN-alpha 2b at 6.0 million U/m2/day thrice weekly plus s.c. rIL-2 at 14.4-18.0 million IU/m2/day on days 1 and 2, followed by 4.8 million IU/m2/day, 5 days per week. RESULTS Subcutaneous immunotherapy as administered in this study was well tolerated in the outpatient setting. Thus, there were no treatment-related deaths, and no patient developed grade III or IV (WHO) toxicity. Subcutaneous rIL-2 as a single agent produced grade II anemia and granulocytopenia in 7% of patients, respectively. In combination with s.c. rIFN-alpha, s.c. rIL-2 yielded grade II anemia and granulocytopenia in 8 and 14% of patients, respectively. In comparison, rIFN-alpha as a single agent produced grade III anemia and grade I granulocytopenia in 5 and 20% of patients, respectively. Upon s.c. rIL-2/rIFN-alpha combination therapy, a mean hemoglobin nadir of 114.4 g/l (p < 0.0001 when compared to baseline) was noted, and the mean granulocyte nadir was 2.3/nl (p < 0.0005). These mild laboratory changes due to cytokine-induced hematotoxicity were in marked contrast to severe anemia, thrombocytopenia, and granulocytopenia reported upon i.v. rIL-2 therapy. CONCLUSIONS Palliative s.c. rIL-2-based immunotherapy as used in this study abrogates profound hematotoxicity, previously seen upon rIL-2-based i.v. immunotherapy. Subcutaneous rIL-2/rIFN-alpha combination therapy can be given in the ambulatory setting with good practicability and excellent safety. This outpatient regimen is as effective in advanced renal cell cancer as the most aggressive i.v. rIL-2-based protocols reported.

Interleukin-2 and other cytokines

In combining recombinant human interleukin-2 (IL-2) with other cytokines, a plethora of immunologic effects are exploited. Most of these host defense mechanisms, effects on tumour growth and on tumour differentiation are not yet fully understood [72].

Cytokine-based biotherapy of gastrointestinal tumors

Over the past 20 years the administration of cytokines has emerged as an important fourth modality for the treatment of human cancer. Advances in the field of therapy of gastrointestinal tumors have become a major focus of current research, given the lack of progress of conventional antineoplastic therapy in most of these tumors. Among the heterogeneous group of gastrointestinal malignancies, novel therapeutic strategies have been employed for each individual tumor type, and cytokines (interferon-a) have gained an established role in the treatment of advanced carcinoid tumors. Although our understanding of the mechanisms of biological response modification is still limited, further improvement in the management of gastrointestinal malignancies can be expected from multimodality therapy regimens employing cytokines in combination with other biological response modifiers, chemotherapeutic agents, active-specific immunotherapy, and immunotoxin- and radionuclide-conjugated monoclonal antibodies. A wide range of clinical and preclinical studies have been conducted in colorectal carcinoma; however, potential therapeutic benefit of cytokine-based biotherapy has not been fully defined. Therefore, large-scale, i.e., multicenter, studies are required to quantify the potential therapeutic effects of cytokines in gastrointestinal tumors.