Predicting response to IL-2 therapy for metastatic melanoma

Evaluation of: Sabatino M, Kim-Schulz S, Panelli MC et al. Serum vascular endothelial growth factor and fibronectin predict clinical response to high-dose IL-2 therapy. J. Clin. Oncol. 27(16), 2645–2652 (2009).

IL-2 therapy induces durable responses in a small proportion of patients with metastatic melanoma, a disease refractory to most anticancer treatments. However, administration requires intensive medical support; due to the risk of severe side effects, hence identification of likely responders or nonresponders would be of great clinical value. This study prospectively examined patient serum pre- and post-IL-2 infusion and analyzed for protein markers of response, in training and test sets. Elevated baseline levels of VEGF and fibronectin predicted a lack of response to IL-2 therapy and worse overall outcome. Serum VEGF is an easily measured biomarker and is a potentially clinically useful test to exclude patients unlikely to benefit from IL-2 treatment, if the results of this study are replicable. Significant biological questions are raised by this study and, furthermore, the use of IL-2 in the context of emerging molecular therapies for metastatic melanoma needs careful consideration.     

Treatment of metastatic renal cell carcinoma

Purpose  To review the treatment of metastatic renal cell carcinoma (RCC), including the use of new targeted therapies. Methods  A search of MEDLINE (1966 to August 2008) and American Society of Clinical Oncology Meeting abstracts (2005 to May 2008) was preformed using the search terms bevacizumab, everolimus, interferon-alfa (IFN-α), interleukin-2 (IL-2), sorafenib, sunitinib, temsirolimus, and RCC. Articles most pertinent to the treatment of metastatic RCC are reviewed. Results  The treatment of metastatic RCC has undergone a paradigm shift over the past 5 years from biologic response modifiers to new targeted therapies. Historically, response rates for the biological response modifiers, aldesleukin (IL-2), and IFN-α were approximately 15%. Recently, three targeted agents, sorafenib, sunitinib, and temsirolimus have been approved for the treatment of RCC. Additionally, bevacizumab has been investigated and shown to increase progression free survival in RCC. IL-2 remains the only agent to induce complete, durable remissions; however, many patients are not eligible for this therapy. Newer agents (sorafenib, sunitinib, and temsirolimus) have shown to be superior to IFN-α or placebo and bevacizumab combined with IFN-α has shown activity when compared to IFN-α alone. Unlike IL-2, the greatest benefit obtained with targeted therapies is in achieving stable disease (SD). Despite their benefit, targeted therapies have never been compared with each other in clinical trials and choosing the most appropriate agent remains challenging. To date, the optimal sequence or combination of treatments has not been defined; however, everolimus has recently demonstrated activity in patients progressing on targeted therapy. Conclusions  IL-2 remains the most active regimen in inducing complete responses; however, its use is accompanied by substantial morbidity and is limited to those with a good performance status. Targeted therapies are also efficacious in the treatment of RCC, with the major benefit being induction of SD. Future research will better define the sequencing of therapies, as well as, explore the activity of novel combination regimens.     

Advanced renal cell carcinoma

Opinion statement Advanced renal cell carcinoma (RCC) is a disease that is highly resistant to systemic therapy and is difficult to treat. Nephrectomy should be seriously considered in patients who present with metastatic disease prior to systemic therapy, and surgery remains a reasonable option in patients who present with resectable metastases. Numerous studies with many different treatment modalities, including chemotherapy, immunotherapy, and radiation therapy, have failed to consistently benefit patients, with no single agent or combination therapy showing a reproducible response proportion of 20% or higher. Interleukin-2 (IL-2) and interferon-alfa (IFN alfa)-based therapies remain the most commonly used agents to treat patients with advanced disease, demonstrating low but reproducible response proportions in the 10% to 20% range, with durable responses of 5% or less. Recent randomized studies demonstrate a survival advantage for patients receiving systemic IFN-based therapy, but this advantage is marginal. Novel treatment strategies are being investigated, with some encouraging early results using vaccines and allogeneic bone marrow transplant. The identification of new agents with more effective antitumor activity is a high priority in the treatment of advanced RCC.     

Update on novel agents in renal cell carcinoma

Renal cell carcinoma (RCC) is a disease with a variable natural history, sometimes presenting with a very indolent course and other times with an aggressive clinical course and unusual sites of metastasis. Surgical resection for stage I–III tumors represents the standard of care and is the only curative option available to patients. However, 40–50% of patients develop metastatic disease. Prior to the advent of targeted therapy, cytokine therapy was the only treatment for RCC. The administration of high-dose, bolus IL-2 has historically produced consistent, durable responses in a small percentage of patients with advanced RCC. The use of IFN-α is currently limited to combination therapies. Multiple new agents targeting the VEGF pathway have been tested and approved, including sunitinib, sorafenib and bevacizumab, with others waiting in the wings. In the majority of cases these drugs induce disease stabilization with eventual disease progression. Hence additional new pathways are being targeted and studied. Mechanisms of drug resistance, novel combinations, sequences and schedules are the focus of current clinical investigations. This review provides an updated list of the novel targeted agents in advanced clinical development for metastatic RCC.     

Immunotherapy of metastatic renal cell carcinoma

In 1992, high-dose bolus interleukin (IL)-2 was granted Food and Drug Administration approval based on its ability to produce durable complete responses in a small number of patients with metastatic renal cell carcinoma (RCC). However, the substantial toxicity and limited efficacy that is associated with IL-2 has narrowed its application to highly selected patients treated at specialized centers. In recent years, the relative merits of low- and high-dose cytokine regimens have been clarified by the results of 4 randomized trials. Taken together, these studies suggest that high-dose IV bolus IL-2 is superior in terms of response rate and possibly response quality to regimens that involve either low-dose IL-2 and interferon-alpha, intermediate- or low-dose IL-2 alone, or low-dose interferon-alpha alone. More significantly, investigations associated with these trials suggest that the potential exists for identifying predictors of response (or resistance) and limiting IL-2 therapy to those most likely to benefit. The Cytokine Working Group has launched the high-dose IL-2 "select" trial to determine, in a prospective fashion, if the predictive model proposed by Atkins et al. can identify a group of patients with advanced RCC who are significantly more likely to respond to high dose IL-2-based therapy ("good" risk) than a historical, unselected patient population. For patients unlikely to benefit from IL-2, are unable to receive it or who progress after IL-2, the emergence of molecularly targeted therapies offers hope for improved clinical outcome. As the list of effective therapies for metastatic RCC grows, improvements in patient selection and more "targeted" approaches will be required to optimize the benefits of cytokine therapy in metastatic RCC.     

Depletion of normal B cells with rituximab as an adjunct to IL-2 therapy for renal cell carcinoma and melanoma.

BACKGROUND: We postulated that in patients with metastatic renal cell carcinoma (RCC) or melanoma, depletion of normal B cells using the anti-CD20 mAb rituximab before treatment with low-dose interleukin (IL)-2 would improve clinical outcome. PATIENTS AND METHODS: Rituximab (375 mg/m(2)) weekly for 4 weeks. IL-2 [11 (million units) daily] s.c., 4 days a week for weeks 5-8, followed by a 2-week rest (weeks 9 and 10). Patients without disease progression continued on IL-2. Disease re-evaluation was performed after rituximab and after every course of IL-2. RESULTS: Fifteen patients with RCC and six with melanoma were enrolled. One patient had a partial response and seven patients had stable disease. Toxicities were similar to those expected with IL-2 alone, and there were no grade 4 events. Circulating B cells were depleted in all patients. The subsequent low-dose IL-2 increased absolute numbers of natural killer cells, activated CD4(+) and activated CD8(+) T cells. Expanded T cells produced interferon-gamma, but not IL-4. Proliferation of peripheral blood lymphocytes to phytohemagglutinin was diminished following rituximab treatment, suggesting that B cells participate in this response in vitro. CONCLUSIONS: Our results suggest that depletion of circulating B cells with rituximab does not increase the response rate, alter the toxicity profile or change the biological activity in response to low-dose IL-2 in patients with RCC or melanoma.     

Cytokine therapy: a standard of care for metastatic renal cell carcinoma?

Metastatic renal cell carcinoma (RCC) is refractory to standard cytotoxic chemotherapy regimens. The rationale for the use of cytokines in RCC is based on compelling evidence that RCC is sensitive to immunologic manipulation. Cytokine-based therapy with interleukin-2 (IL-2) or interferon (IFN)-α can result in objective tumor responses in as many as 15% of patients, and in selected patients, these responses can be durable. The development of targeted therapies for clear-cell RCC with the potential for greater antitumor activity and less toxicity has brought into question the role of cytokines in this patient population. However, no noncytokine therapy to date has proven curative in patients with metastatic RCC. Until results from ongoing trials clearly demonstrate superiority of newer agents over IFN-α or IL-2, these agents should remain a standard of care for the treatment of RCC.     

Treatment selection for patients with metastatic renal cell carcinoma: identification of features favoring upfront IL-2-based immunotherapy

The availability of approved agents with distinct mechanisms of action (immunotherapy, vascular endothelial growth factor pathway, and mTOR inhibitors) has complicated treatment decisions for patients with advanced kidney cancer. High-dose IL-2 therapy is the only treatment that can produce durable complete responses; however, it has significant side effects and the vast majority of patients do not benefit. Thus, identifying the optimal patients to receive first-line IL-2 therapy is a priority. Past studies have identified some clinical features that might be associated with benefit from IL-2-based immunotherapy. Subsequent investigations of tumors from patients treated with IL-2 suggested that response was unlikely in patients with tumors with papillary features or low carbonic anhydrase IX (CAIX) expression. A model combining histologic features and CAIX expression separated patients into two groups of roughly equal size, with 96% of long-term responding patients being in the favorable prognostic group. This model is currently undergoing prospective validation. More recent studies involving gene expression profiling and array CGH have begun to identify additional features that might predict response to IL-2 therapy. Taken together, these data offer the possibility to limit the use of this toxic therapy to those most likely to benefit.     

Treatment selection for patients with metastatic renal cell carcinoma: identification of features favoring upfront IL-2-based immunotherapy

The availability of approved agents with distinct mechanisms of action (immunotherapy, vascular endothelial growth factor pathway, and mTOR inhibitors) has complicated treatment decisions for patients with advanced kidney cancer. High-dose IL-2 therapy is the only treatment that can produce durable complete responses; however, it has significant side effects and the vast majority of patients do not benefit. Thus, identifying the optimal patients to receive first-line IL-2 therapy is a priority. Past studies have identified some clinical features that might be associated with benefit from IL-2-based immunotherapy. Subsequent investigations of tumors from patients treated with IL-2 suggested that response was unlikely in patients with tumors with papillary features or low carbonic anhydrase IX (CAIX) expression. A model combining histologic features and CAIX expression separated patients into two groups of roughly equal size, with 96% of long-term responding patients being in the favorable prognostic group. This model is currently undergoing prospective validation. More recent studies involving gene expression profiling and array CGH have begun to identify additional features that might predict response to IL-2 therapy. Taken together, these data offer the possibility to limit the use of this toxic therapy to those most likely to benefit.     

Adjuvant high-dose bolus interleukin-2 for patients with high-risk renal cell carcinoma: a cytokine working group randomized trial.

PURPOSE: This prospective, randomized, controlled phase III trial assessed high-dose bolus interleukin-2 (IL-2) postoperatively in patients with high-risk renal cell carcinoma (RCC). PATIENTS AND METHODS: Eligibility requirements were resected locally advanced (LA; T3b-4 or N1-3) or metastatic (M1) RCC, no prior systemic therapy, and excellent organ function. Randomized assignment was to one course of IL-2 (600,000 U/kg every 8 hours on days 1 to 5 and days 15 to 19 [maximum 28 doses]) or observation. The study was designed and powered to show an improvement in predicted 2-year disease-free survival (DFS) from 40% for the observation group to 70% for the treatment group. The accrual goal was 68 patients with LA disease, with 34 patients per treatment arm. Metastasectomy patients were to be analyzed separately because of their unpredictable natural history. RESULTS: Sixty-nine patients were enrolled onto the study (44 LA and 25 M1 patients). Toxic effects of IL-2 were as anticipated; no unexpected serious adverse events or treatment-related deaths occurred. Early closure occurred when an interim analysis determined that the 30% improvement in 2-year DFS could not be achieved despite full accrual. Sixteen of 21 LA patients receiving IL-2 experienced relapse, compared with 15 of 23 patients in the observation arm (P =.73); in the LA group, three deaths occurred in the IL-2 arm, and five deaths occurred in the observation arm (P =.38). Analysis including metastasectomy patients made no difference in DFS or overall survival. CONCLUSION: One course of high-dose bolus IL-2, though feasible, did not produce the ambitious clinically meaningful benefit anticipated when administered postoperatively to patients with resected high-risk RCC.     

High-dose interleukin-2 for the treatment of metastatic renal cell carcinoma : a retrospective analysis of response and survival in patients treated in the surgery branch at the National Cancer Institute between 1986 and 2006

BACKGROUND: The treatment of metastatic renal cell carcinoma (RCC) with high-dose interleukin-2 (HD IL-2) has resulted in durable tumor regression in a minority of patients. The current study presents the authors' 20-year experience administering this immunotherapeutic agent. METHODS: Patients with metastatic RCC (n = 259) were treated with HD IL-2 alone from January 13, 1986 through December 31, 2006 at the Surgery Branch of the National Cancer Institute. Potential predictive factors for response and survival, both pretreatment and treatment-related, were first subjected to univariate analysis and then to multivariate logistic regression or a Cox proportional hazards model. Finally, the authors investigated Memorial Sloan-Kettering Cancer Center (MSKCC) prognostic factors for survival to assess their predictive value in the patient population in the current study. RESULTS: A total of 23 patients experienced a complete response and 30 patients achieved a partial response, for an overall objective response rate of 20%. All partial responders had developed disease recurrence at the time of last follow-up, but only 4 complete responders had experienced disease recurrence by that time. Despite toxicities, only 2 patients developed treatment-related mortalities over this same time period. A higher baseline weight (P = .05) and MSKCC prognostic factors (P = .02) were found to be the variables most associated with response. For survival >4 years and overall survival, several pretreatment and treatment-related factors maintained significance, but none more so than response (P < .0001). CONCLUSIONS: HD IL-2 can induce complete tumor regression in a small number of patients, and many patients have experienced extended disease-free intervals. Given its relative safety, HD IL-2 should still be considered a first-line therapy in patients with metastatic RCC who have an overall good performance status.     

A combination of YM-155, a small molecule survivin inhibitor,and IL-2 potently suppresses renal cell carcinoma in murine model

YM155, a small molecule inhibitor of the antiapoptotic protein survivin, has been developed as a potential anti-cancer drug. We investigated a combination therapy of YM155 and interleukin-2 (IL-2) in a mouse model of renal cell carcinoma (RCC). YM155 caused cell cycle arrest and apoptosis in renal cancer (RENCA) cells. Next, luciferase-expressing RENCA cells were implanted in the left kidney and the lung of BALB/c mice to develop RCC metastatic model. In this orthotopic renal and metastatic lung tumors models, YM155 and IL-2 additively decreased tumor weight, lung metastasis, and luciferin-stained tumor images. Also, the combination significantly suppressed regulatory T cells and myeloid-derived suppressor cells compared with single agent treatment. We suggest that a combination of YM155 and IL-2 can be tested as a potential therapeutic modality in patients with RCC.     

Clinical outcome of combined immunotherapy with low-dose interleukin-2 and interferon-α for Japanese patients with metastatic renal cell carcinoma who had undergone radical nephrectomy: a preliminary report

Background The objective of this study was to evaluate the clinical outcome of combined immunotherapy with interferon-α (IFN-α) and low-dose interleukin-2 (IL-2) for Japanese patients with metastatic renal cell carcinoma (RCC) who had undergone radical nephrectomy. Methods This study included 13 patients who were diagnosed as having metastatic RCC following radical nephrectomy. These patients received a subcutaneous injection of IFN-α (6 × 10⁶ IU per day) three times per week and an intravenous injection of IL-2 (1.4 × 10⁶ IU per day) twice per week. Tumor response was evaluated every 16 weeks, and as a rule, this weekly regimen was repeated 50 times in patients with evidence of objective response or stable disease. Results One of the 13 patients dropped out because of severe toxicity; hence, 12 patients were evaluable, with a median follow-up period of 18 months after the start of this combined therapy. Six patients (50.0%) achieved objective responses, with 1 complete response (CR), while only 2 (16.7%) demonstrated progressive disease. The median duration of response in the 6 responders was 13.5 months. Toxicity associated with this combined immunotherapy was limited to WHO grade 1 or 2 in these 12 patients. All patients were alive at last follow-up, and 2 remain disease-free after 1 additional patient showed a CR following surgical resection of the remaining metastatic disease. Conclusion Our preliminary experience suggests that long-term, repeated treatment with IFN-α and low-dose IL-2 is feasible in Japanese patients with metastatic RCC who have undergone radical nephrectomy. Although it will be necessary to accumulate data from a larger number of patients with a longer follow-up period, the combined immunotherapy tested in this study may become the preferred therapy for Japanese patients with metastatic RCC.     

Efficacy of large doses of IL-2-activated human leukocyte antigen haploidentical peripheral blood stem cells on refractory metastatic renal cell carcinoma

Traditional immunotherapy for patients with refractory metastatic renal cell carcinoma (RCC) is limited because the tumors themselves induce immunosuppression. The aim of this article was to evaluate the clinical efficacy of the infusion of a high dose of interleukin (IL)-2-activated allogeneic haploidentical peripheral blood stem cells (haplo-PBSCs) in patients with advanced intractable RCC. Ten advanced RCC patients and their haploidentical relatives, who were haplo-PBSC donors, were enrolled in this study. All patients accepted one cycle of activated haplo-PBSCs. The clinical and immunologic responses were evaluated. A range from 2.3 to 5.5×10(10) of activated haplo-PBSCs were harvested after exposure to recombinant human IL-2 (rhIL-2), along with a significant increase in the proportion of natural killer cells and activated lymphocytes (CD69+ and CD25+). Enhanced cytotoxicity of haplo-PBSCs for RCC was also observed. After treatment, 2 (2/10) cases of partial remission, 6 (6/10) cases of stable disease, and 2 (2/10) cases of progressive disease were identified in these 10 patients. The median progression-free survival of the 10 patients was 5.5 months (3-14 months). The adoptive transfusion of IL-2-activated haplo-PBSCs can induce sustained antitumor effects for advanced intractable RCC patients who have had no response to conventional immunotherapy.     

Interleukin-2 therapy of metastatic renal cell carcinoma--predictors of response

For the past 15 years, immunoreactive cytokines have been the mainstay of treatment for metastatic renal cancer. High-dose bolus interleukin-2 (IL-2) was granted US Food and Drug Administration (FDA) approval in 1992 based on its ability to produce durable complete responses (CRs) in a small number of patients. Unfortunately, the toxicity, expense, and restricted accessibility of high-dose IL-2 make it a poor standard therapy. Regimens involving lower doses of IL-2 either alone or in combination with interferon (IFN) have generally produced fewer tumor regressions and these regressions were of less overall quality. Recent efforts have focused on trying to identify factors predictive of response to IL-2 therapy so that this treatment can be limited to those most likely to benefit. This year, investigators will launch a clinical trial designed to prospectively determine if patients who are more likely to respond to high-dose IL-2 can be identified prior to starting therapy.     

Role of immunotherapy for renal cell cancer in 2011

High-dose interleukin-2 (IL-2) and interferon were the most commonly administered therapies before the recent introduction of targeted agents, including vascular endothelial growth factor and mammalian target of rapamycin pathway inhibitors. Although the new agents result in a progression-free survival benefit, high-dose IL-2 remains the only agent with proven efficacy in producing durable complete and partial responses in patients with metastatic renal cell carcinoma (RCC). Furthermore, although the use of single-agent interferon has decreased significantly since the introduction of targeted therapy, it remains in the frontline setting in combination with bevacizumab as a result of 2 large phase III trials. Lastly, improved understanding of immune regulation has led to the advancement of targeted immunotherapy using immune checkpoint inhibitors that have shown promising activity and are moving forward in clinical development. This article focuses on the current status of immunotherapy in the management of metastatic RCC.     

Role of surgery for locally advanced and metastatic renal cell carcinoma

Both locally advanced and metastatic renal cell carcinoma (RCC) present a challenge in terms of their optimal management. This article reviews the literature and evaluates the role of surgery in the treatment of advanced RCC. Surgery is the optimal treatment for locally advanced RCC and minimal, resectable, metastatic disease. Patients with metastatic disease, and some forms of locally advanced disease, may also benefit from multimodal management with local surgical therapy and systemic treatment using either immunotherapy or targeted therapy. Regardless of the disease stage, patients with locally advanced or metastatic RCC represent heterogenous patient populations with different disease characteristics and risk factors. Individualization of care in the setting of a sound oncologic framework may optimize the risk/benefit ratio within individual patient cohorts.     

Cytokine secretion associated with the clearance of apoptotic bodies in renal cell carcinoma patients

The factors determining the outcome of immunotherapy in metastatic renal cell carcinoma (RCC) patients remain elusive. Macrophages from normal donors that phagocytose apoptotic cells secrete the immunosuppressive cytokine IL-10 in vitro. Conversely, IL-10 genetic deletion enhances the immunogenicity of apoptotic tumor cells in vivo. Elevated pre-treatment levels of IL-10 are associated with an unfavorable outcome of RCC. We examined whether the ability to release IL-10 by macrophages from RCC patients that phagocytosed apoptotic cells correlated with the outcome of immunotherapy. To this aim, we derived macrophages from 30 patients with metastatic RCC and from 21 healthy subjects (11 sex- and age-matched healthy controls and 10 younger donors). Patients either had a clinical response after immunotherapy, with a median survival after treatment of more than 18 months (n = 16), or were beginning immunotherapy after diagnosis of metastatic disease (n = 14). Macrophages from responding patients challenged with apoptotic cells released significantly less IL-10 than controls (p = 0.0075) and recently diagnosed patients (p = 0.0198), as ascertained by a 2-sided Student's t-test. This was not because macrophages from responding patients lost the ability to secrete IL-10, because antibody opsonization of apoptotic cells rescued IL-10 secretion. In contrast, macrophages from all groups of donors released similar amounts of TNF-alpha. The failure in IL-10 secretion by engulfing macrophages of responding subjects may exalt the immunogenicity of dying tumor cells, contributing to the success of immunotherapy.     

Survival in renal cell carcinoma-a randomized evaluation of tamoxifen vs interleukin 2, alpha-interferon (leucocyte) and tamoxifen.

Metastatic renal cell carcinoma (RCC) has a poor prognosis. Conventional treatment strategies, including chemotherapy and hormonal therapy, have limited value. Although encouraging results have been achieved in terms of objective response using immunological manipulations, no conclusive studies yet exist with a controlled comparative evaluation of survival. Therefore, the present study was undertaken, which compared one of the present (and presumed best) treatments, interleukin 2/interferon-alpha (IL-2/IFN-alpha) and tamoxifen, with a control arm of tamoxifen only. Tamoxifen has been shown to potentiate in vivo anti-tumour activity of IL-2, and because of its non-toxic behaviour it was included in both groups. The study was open, randomized and included seven institutions in Sweden. The patients were stratified according to the different centres involved. An interim analysis was planned when a minimum of 100 patients were evaluable. The 128 patients finally included had a histologically documented metastatic RCC, with a life expectancy of more than 3 months, a performance status WHO 0-2 and no prior chemo- or immunotherapy. Informed consent was obtained from each patient. The patients randomized to the control arm (n = 63) received only tamoxifen 40 mg p.o. daily for at least 1 year or until progression. The patients (n = 65) randomized to biotherapy received subcutaneous recombinant IL-2, leucocyte IFN-alpha in a treatment cycle of 42 days, as well as tamoxifen p.o. In the absence of undue toxicity or disease progression, these patients received one additional treatment cycle of 42 days followed by maintenance treatment, consisting of 5 days therapy every 4 weeks, for 1 year, or until proven progression. Only two patients in the tamoxifen-only group received immunotherapy when the disease progressed, but without any beneficial effect. All patients received appropriate local treatment when indicated. The interim analysis demonstrated no survival advantage for either group, and therefore further inclusion of patients was stopped. The median follow-up was 11 months (range 0.4-48 months). The final survival analysis showed no significant differences between the two treatment arms in so far as comparison from the day of diagnosis of primary disease, from the day of first evidence of metastatic spread, or from the onset of treatment. This was valid both when the evaluation was performed with regard to intention to treat and when the analysis was directed only to patients that managed at least one treatment cycle (42 days) of IL-2/IFN-alpha. The adverse effects were more pronounced in the IL-2/IFN-alpha group. Although the number of patients is limited, the results raise doubt concerning immunotherapy with IL-2 and IFN-alpha as a routine treatment in the management of advanced RCC. The difference in cost of drugs and health care (drug costs per patient: IL-2/IFN-alpha $27000 vs tamoxifen $360) as well as adverse effects caused by IL-2/IFN-alpha are also factors of importance. The study emphasizes the need for more effort to find the ''optimal schedule'' of immunotherapy, as well as the need for randomized controlled studies before approval of a new treatment in the routine setting.     

A phase II study of interleukin-2 and lymphokine-activated killer cells in patients with metastatic malignant melanoma

Thirty-six patients with metastatic melanoma were entered into a study of the therapeutic efficacy of adoptive immunotherapy with high-dose interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells. Thirty-two patients who received all components of the therapy are evaluable for response, and all patients are evaluable for toxicity. Sites of disease included lung, liver, subcutaneous nodules, and intra-abdominal metastases. One complete response (CR) and five partial responses (PRs) resulted from treatment (19% response rate). The median response duration was 5 months, with the durable CR continuing at 31+ months and one durable PR continuing for 13 months. Sites of response included lung, liver, subcutaneous nodules, and lymph nodes. Response, response duration, or site of response did not correlate with the total dose of IL-2 administered, rebound lymphocytosis, or the number of LAK cells infused. Toxicity included hypotension, fluid retention with a "capillary leak syndrome" in most patients, and transient multiorgan dysfunction that resolved promptly after the completion of therapy. Adverse cardiac events occurred in 16% of patients, with one myocardial infarction leading to a death. This study confirms the activity of the initial IL-2/LAK cell regimen in metastatic melanoma reported by Rosenberg et al, supporting the concept of adoptive immunotherapy as an important new treatment approach for this disease.