Michael T. Lotze

A progress report on the treatment of 157 patients with advanced cancer using lymphokine-activated killer cells and interleukin-2 or high-dose interleukin-2 alone.

We studied the effects of adoptive immunotherapy with lymphokine-activated killer (LAK) cells plus interleukin-2 or therapy with high-dose interleukin-2 alone in 157 patients with metastatic cancer for whom standard therapy had proved ineffective or no standard effective treatment was available. One hundred eight patients were treated with 127 courses of LAK cells plus interleukin-2, and 49 patients were treated with 53 courses of high-dose interleukin-2 alone. Of 106 evaluable patients receiving LAK cells plus interleukin-2, 8 had complete responses, 15 had partial responses, and 10 had minor responses. The median duration of response was 10 months among those with complete responses and 6 months among those with partial responses; the patient with the longest complete response was still in remission 22 months after treatment. Of 46 evaluable patients treated with high-dose interleukin-2 alone, 1 had a complete response (remission greater than 4 months), 5 had partial responses (2, greater than 3, greater than 5, 7, and greater than 11 months), and 1 had a minor response. Seven of the total of nine complete responses still remain in remission. Hypotension, weight gain, oliguria, and elevation of bilirubin and creatinine levels were common, but these side effects resolved promptly after interleukin-2 administration was stopped. There have been four treatment-related deaths among these 157 patients. This immunotherapeutic approach can result in marked tumor regression in some patients for whom no other effective therapy is available at present. Determining its ultimate role in cancer therapy awaits further attempts to increase the therapeutic efficacy of treatment and decrease its toxicity and complexity.

Observations on the systemic administration of autologous lymphokine-activated killer cells and recombinant interleukin-2 to patients with metastatic cancer

We describe here the preliminary results of the systemic administration of autologous lymphokine-activated killer (LAK) cells and the recombinant-derived lymphokine interleukin-2 to patients with advanced cancer. This regimen was based on animal models in which the systemic administration of LAK cells plus interleukin-2 mediated the regression of established pulmonary and hepatic metastases from a variety of murine tumors in several strains of mice. We treated 25 patients with metastatic cancer in whom standard therapy had failed. Patients received both 1.8 to 18.4 X 10(10) autologous LAK cells, generated from lymphocytes obtained through multiple leukaphereses, and up to 90 doses of interleukin-2. Objective regression of cancer (more than 50 per cent of volume) was observed in 11 of the 25 patients: complete tumor regression occurred in one patient with metastatic melanoma and has been sustained for up to 10 months after therapy, and partial responses occurred in nine patients with pulmonary or hepatic metastases from melanoma, colon cancer, or renal-cell cancer and in one patient with a primary unresectable lung adenocarcinoma. Severe fluid retention was the major side effect of therapy, although all side effects resolved after interleukin-2 administration was stopped. Further development of this approach and additional patient follow-up are required before conclusions about its therapeutic value can be drawn.

Use of tumor-infiltrating lymphocytes and interleukin-2 in the immunotherapy of patients with metastatic melanoma. A preliminary report.

Lymphocytes extracted from freshly resected melanomas can be expanded in vitro and can often mediate specific lysis of autologous tumor cells but not allogeneic tumor or autologous normal cells. We treated 20 patients with metastatic melanoma by means of adoptive transfer of these tumor-infiltrating lymphocytes and interleukin-2, after the patients had received a single intravenous dose of cyclophosphamide. Objective regression of the cancer was observed in 9 of 15 patients (60 percent) who had not previously been treated with interleukin-2 and in 2 of 5 patients (40 percent) in whom previous therapy with interleukin-2 had failed. Regression of cancer occurred in the lungs, liver, bone, skin, and subcutaneous sites and lasted from 2 to more than 13 months. Toxic effects of interleukin-2 occurred, although the treatment course was short (five days); these side effects were reversible. It appears that in patients with metastatic melanoma, this experimental treatment regimen can produce higher response rates than those achieved with interleukin-2 administered alone or with lymphokine-activated killer cells. It is too early to determine whether this new form of immunotherapy can improve survival, but further trials seem warranted.

Gene transfer into humans--immunotherapy of patients with advanced melanoma, using tumor-infiltrating lymphocytes modified by retroviral gene transduction.

BACKGROUND AND METHODS Treatment with tumor-infiltrating lymphocytes (TIL) plus interleukin-2 can mediate the regression of metastatic melanoma in approximately half of patients. To optimize this treatment approach and define the in vivo distribution and survival of TIL, we used retroviral-mediated gene transduction to introduce the gene coding for resistance to neomycin into human TIL before their infusion into patients--thus using the new gene as a marker for the infused cells. RESULTS Five patients received the gene-modified TIL. All the patients tolerated the treatment well, and no side effects due to the gene transduction were noted. The presence and expression of the neomycin-resistance gene were demonstrated in TIL from all the patients with Southern blot analysis and enzymatic assay for the neomycin phosphotransferase coded by the bacterial gene. Cells from four of the five patients grew successfully in high concentrations of G418, a neomycin analogue otherwise toxic to eukaryotic cells. With polymerase-chain-reaction analysis, gene-modified cells were consistently found in the circulation of all five patients for three weeks and for as long as two months in two patients. Cells were recovered from tumor deposits as much as 64 days after cell administration. The procedure was safe according to all criteria, including the absence of infections virus in TIL and in the patients. CONCLUSIONS These studies demonstrate the feasibility and safety of using retroviral gene transduction for human gene therapy and have implications for the design of TIL with improved antitumor potency, as well as for the possible use of lymphocytes for the gene therapy of other diseases.

Experience with the use of high-dose interleukin-2 in the treatment of 652 cancer patients.

We have administered 1039 courses of high-dose interleukin-2 (IL-2) to 652 cancer patients. Five hundred ninety-six patients had metastatic cancer that either had failed standard effective therapies or had disease for which no standard effective therapy existed, and 56 patients were treated in the absence of evaluable disease in the adjuvant setting. IL-2 was administered either alone (155 patients) or in conjunction with activated immune cells such as lymphokine activated killer (LAK) cells (214 patients) or tumor infiltrating lymphocytes (TIL) (66 patients), with other cytokines such as alpha interferon (a-IFN)(128 patients) or tumor necrosis factor (TNF)(38 patients), with monoclonal antibodies (32 patients), or with the chemotherapeutic agent cyclophosphamide (19 patients). Initial results with the treatment of high-dose IL-2 alone or in conjunction with LAK cells have indicated that objective regressions of cancer can be achieved in 20% to 35% of patients with selected advanced metastatic cancers. Although most responses have been seen in patients with metastatic renal cell cancer, melanoma, colorectal cancer, and non-Hodgkins lymphoma, many histologic types of cancer have not been treated in significant numbers. These regressions can be durable; of 18 patients achieving a complete response, ten have not experienced recurrence at intervals from 18 to 52 months. Although combinations of IL-2 with TNF do not appear to result in increased responses, there is a suggestion in our initial phase I studies that the combination of a-IFN and IL-2 is more effective than the administration of cytokine alone and this combination deserves further study. Similarly the adoptive transfer of TIL in conjunction with IL-2 also appears to be more effective than the use of IL-2 alone. The toxic side effects in patients treated with high-dose IL-2 are presented and include malaise, nausea and vomiting, hypotension, fluid retention, and organ dysfunction. Treatment-related deaths were seen in 1% of all treatment courses and in 1.5% of patients. These studies demonstrate that a purely immunologic manipulation can mediate the regression of advanced cancers in selected patients and may provide a base for the development of practical, effective biologic treatments for some cancer patients.

Immunotherapy of patients with advanced cancer using tumor-infiltrating lymphocytes and recombinant interleukin-2: a pilot study.

Clinical investigations using the adoptive transfer of lymphokine-activated killer (LAK) cells and recombinant interleukin-2 (rIL-2) to treat patients with advanced cancer have yielded encouraging results. We have thus sought ways to enhance the effectiveness of adoptive immunotherapy while minimizing its toxic side effects. Murine experiments have identified tumor-infiltrating lymphocytes (TIL) as killer cells more effective than LAK cells and less dependent on adjunctive systemically administered IL-2 to mediate antitumor effects. Accordingly, we performed a pilot protocol to investigate the feasibility and practicality of administering IL-2-expanded TIL to humans with metastatic cancers. Twelve patients, including six with melanoma, four with renal cell carcinoma, one with breast carcinoma, and one with colon carcinoma, were treated with varying doses and combinations of TIL (8.0 X 10(9) to 2.3 X 10(11) cells per patient), IL-2 (10,000 to 100,000 U/kg three times daily to dose-limiting toxicity), and cyclophosphamide (CPM) (up to 50 mg/kg). Two partial responses (PR) to therapy were observed: pulmonary and mediastinal masses regressed in a patient with melanoma, and a lymph node mass regressed in a patient with renal cell carcinoma. One additional patient with breast cancer experienced a partial regression of disease in lymph nodal and cutaneous sites with complete elimination of malignant cells from a pleural effusion, although cutaneous disease recurred at 4 weeks. The toxicities of therapy were similar to those ascribed to IL-2; no toxic effects were directly attributable to TIL infusions. In five of six melanoma patients, TIL demonstrated lytic activity specific for the autologous tumor target in short-term chromium-release assays, distinct from the nonspecific lytic activity characteristic of LAK cells. This study represents an initial attempt to identify and use lymphocyte subsets with enhanced tumoricidal capacity in the adoptive immunotherapy of human malignancies.

Combination therapy with interleukin-2 and alpha-interferon for the treatment of patients with advanced cancer

We performed an escalating dose study of the combined administration of interleukin-2 (IL-2) and alpha-interferon (alpha-IFN) in 94 patients with metastatic cancer. Patients received alpha-IFN at a dose of 3 x 10(6) U/m2 in conjunction with IL-2 at doses of either 1 x 10(6) U/m2 (six patients), 3 x 10(6) U/m2 (32 patients), or 4.5 x 10(6) U/m2 (26 patients). Thirty patients received alpha-IFN at 6 x 10(6) U/m2 plus IL-2 at 4.5 x 10(6) U/m2. Patients each received cytokine as an intravenous bolus infusion every 8 hours for up to 5 consecutive days and after a 10-day rest received a second cycle of combination cytokines. Of the 91 patients evaluable for response, seven patients had a complete regression of cancer, and 18 had a partial regression. At the four increasing dose levels used in patients with renal cell cancer (35 patients) or melanoma (39 patients), objective responses were seen in 17% (of six patients), 24% (of 25 patients), 38% (of 16 patients), and 41% (of 27 patients), respectively. Of the 25 total responding patients, 16 are still responding 5 to 14 months after treatment. The toxicities associated with the combined administration of IL-2 and alpha-IFN were similar to those expected from each agent alone. There was one treatment-related death in the 94 patients treated in this study. Thus, using increasing doses of the combination of IL-2 and alpha-IFN, it appears that response rates may be related to the doses of the cytokines used, and that at the highest doses of these combination cytokines, response rates may be higher than those for either cytokine alone. A prospective randomized trial comparing the cytokine combinations with each cytokine administered alone is necessary as is the extension of this combination cytokine treatment to patients with other types of solid cancer.

Clinical effects and toxicity of interleukin‐2 in patients with cancer

Interleukin‐2 (IL‐2) is a 15,000 dalton glycoprotein produced naturally by human T‐cells during an immune response. IL‐2 has been demonstrated to have substantial activity alone or in combination with the adoptive transfer of lymphokine‐activated killer cells in murine tumor models. IL‐2 derived from both natural (Jurkat human T‐cell tumor) and recombinant (Escherichia coli) sources has been studied in Phase I protocols designed to evaluate toxicity in patients with a variety of solid tumors and to ascertain improvement in clinical parameters and immunologic status. A total of 16 patients (7 with acquired immune deficiency syndrome [AIDS] and 9 with non‐AIDS malignancies) were treated with Jurkat derived IL‐2. The total maximum dose (1.3 × 105 U/kg) was limited only by supply of this reagent. A total of 25 patients have been treated with recombinant IL‐2 (RIL‐2) alone. Dose‐limiting toxicity manifested by marked malaise and weight gain was achieved with doses of RIL‐2 of 106 U/kg as a single bolus or 3000 U/kg/hr. IL‐2 could be administered intraperitoneally with similar toxicity. Minimal renal or hepatic toxicity was demonstrated. Hematologic toxicity was limited to mild anemia (25/25), thrombocytopenia (10/25), and marked reversible eosinophilia (15/25). Pronounced weight gain greater than 2 kg (16/25) occurred in most patients, primarily those who received cumulative doses of greater than 1–3 × 105 U/kg of IL‐2. The weight gain amounted to as much as 10% to 20% of the pretreatment weight over 3 weeks of treatment and limited our ability to give higher doses. Two partial responses (>50% decrease in cross sectional diameters) were seen in two patients with melanoma metastatic to the lung.

Cardiorespiratory effects of immunotherapy with interleukin-2.

The administration of interleukin 2 (IL-2) and lymphokine-activated killer (LAK) cells can mediate the regression of cancer. Treatment with IL-2 is associated with significant cardiorespiratory effects, as well as a leaky capillary syndrome requiring careful fluid management. A mild reversible depression of cardiac function is also associated with IL-2 treatment. All patients treated with recombinant IL-2 alone, with transfer of LAK cells, or with cyclophosphamide between December 1984 and September 1987 (total of 423 treatment courses in 317 total patients) were evaluated as to the development of significant cardiorespiratory toxicity. Of the 423 treatment courses, only 1.8% were associated with severe peripheral edema and only 2.8% and 3.1% respectively, were associated with significant ascites or pleural effusions. Thirty-nine of 423 patients (9.2%) had severe respiratory distress and 27 patients required intubation (6.4%). Cardiovascular effects included tachycardia and hypotension requiring vasopressor administration in 65% and intravenous (IV) fluid administration. Weight gain greater than or equal to 10% of body weight was noted in 32% of the 423 patients. Arrhythmias were primarily supraventricular (9.7%) and responded well to conventional medical treatments. Angina or ischemic changes were noted in 2.6% of patients and myocardial infarction in 1.2%. IL-2 caused peripheral vasodilation, with a significant decrease in peripheral vascular resistance (2,254 +/- 398 v 1,303 +/- 351 dyne.s.cm-5, P less than .0001), and an increase in heart rate (66.2 +/- 10 v 104.3 +/- 9.6 beats/min, P less than .0001). There was also evidence of mild cardiac dysfunction, with a significant decrease in the left ventricular stroke work (LVSW) index (P less than .0001) and ejection fraction (LVEF) (from 58% +/- 10% to 52% +/- 9%, P less than .03). A repeat LVEF performed after 1 to 3 months, had returned to baseline values (60% +/- 10%). A mean 64% increase in the rate of disappearance of radioactive iodine (125I) albumin (P less than .05) consistent with the development of a leaky capillary syndrome was noted. Patients with underlying cardiorespiratory diseases may be at greater risk during IL-2 administration and should not be selected to undergo this treatment.

NIH conference. New approaches to the immunotherapy of cancer using interleukin-2.

Experimental studies in animals have shown that therapy with high-dose interleukin-2 either alone or in combination with lymphokine-activated killer cells can reduce established pulmonary and hepatic metastases. Based on these experiments, recent clinical trials have shown that therapy with high-dose interleukin-2 alone or in combination with lymphokine-activated killer cells can mediate the regression of established metastatic disease in selected patients with advanced malignancy. Of 221 patients with advanced cancer treated with this immunotherapy, 16 have had a complete regression of all metastatic cancer, and an additional 26 have had a partial regression (greater than 50% reduction) of cancer. Toxicity from treatment was primarily due to increased capillary permeability, which led to fluid extravasation and organ dysfunction. Based on these findings, new approaches are being explored, including the use of tumor-infiltrating lymphocytes and combinations of lymphokines. These studies show that the regression of established growing cancer can be mediated by manipulating the immune system.