Randomized placebo-controlled clinical trial of high-dose interleukin-2 in combination with a soluble p75 tumor necrosis factor receptor immunoglobulin G chimera in patients with advanced melanoma and renal cell carcinoma

First-line therapy for adults with advanced renal cell carcinoma: a systematic review and network meta-analysis

BACKGROUND

Since the approval of tyrosine kinase inhibitors, angiogenesis inhibitors and immune checkpoint inhibitors, the treatment landscape for advanced renal cell carcinoma (RCC) has changed fundamentally. Today, combined therapies from different drug categories have a firm place in a complex first-line therapy. Due to the large number of drugs available, it is necessary to identify the most effective therapies, whilst considering their side effects and impact on quality of life (QoL).

OBJECTIVES

To evaluate and compare the benefits and harms of first-line therapies for adults with advanced RCC, and to produce a clinically relevant ranking of therapies. Secondary objectives were to maintain the currency of the evidence by conducting continuous update searches, using a living systematic review approach, and to incorporate data from clinical study reports (CSRs).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, conference proceedings and relevant trial registries up until 9 February 2022. We searched several data platforms to identify CSRs.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating at least one targeted therapy or immunotherapy for first-line treatment of adults with advanced RCC. We excluded trials evaluating only interleukin-2 versus interferon-alpha as well as trials with an adjuvant treatment setting. We also excluded trials with adults who received prior systemic anticancer therapy if more than 10% of participants were previously treated, or if data for untreated participants were not separately extractable.

DATA COLLECTION AND ANALYSIS

All necessary review steps (i.e. screening and study selection, data extraction, risk of bias and certainty assessments) were conducted independently by at least two review authors. Our outcomes were overall survival (OS), QoL, serious adverse events (SAEs), progression-free survival (PFS), adverse events (AEs), the number of participants who discontinued study treatment due to an AE, and the time to initiation of first subsequent therapy. Where possible, analyses were conducted for the different risk groups (favourable, intermediate, poor) according to the International Metastatic Renal-Cell Carcinoma Database Consortium Score (IMDC) or the Memorial Sloan Kettering Cancer Center (MSKCC) criteria. Our main comparator was sunitinib (SUN). A hazard ratio (HR) or risk ratio (RR) lower than 1.0 is in favour of the experimental arm.

MAIN RESULTS

We included 36 RCTs and 15,177 participants (11,061 males and 4116 females). Risk of bias was predominantly judged as being 'high' or 'some concerns' across most trials and outcomes. This was mainly due to a lack of information about the randomisation process, the blinding of outcome assessors, and methods for outcome measurements and analyses. Additionally, study protocols and statistical analysis plans were rarely available. Here we present the results for our primary outcomes OS, QoL, and SAEs, and for all risk groups combined for contemporary treatments: pembrolizumab + axitinib (PEM+AXI), avelumab + axitinib (AVE+AXI), nivolumab + cabozantinib (NIV+CAB), lenvatinib + pembrolizumab (LEN+PEM), nivolumab + ipilimumab (NIV+IPI), CAB, and pazopanib (PAZ). Results per risk group and results for our secondary outcomes are reported in the summary of findings tables and in the full text of this review. The evidence on other treatments and comparisons can also be found in the full text. Overall survival (OS) Across risk groups, PEM+AXI (HR 0.73, 95% confidence interval (CI) 0.50 to 1.07, moderate certainty) and NIV+IPI (HR 0.69, 95% CI 0.69 to 1.00, moderate certainty) probably improve OS, compared to SUN, respectively. LEN+PEM may improve OS (HR 0.66, 95% CI 0.42 to 1.03, low certainty), compared to SUN. There is probably little or no difference in OS between PAZ and SUN (HR 0.91, 95% CI 0.64 to 1.32, moderate certainty), and we are uncertain whether CAB improves OS when compared to SUN (HR 0.84, 95% CI 0.43 to 1.64, very low certainty). The median survival is 28 months when treated with SUN. Survival may improve to 43 months with LEN+PEM, and probably improves to: 41 months with NIV+IPI, 39 months with PEM+AXI, and 31 months with PAZ. We are uncertain whether survival improves to 34 months with CAB. Comparison data were not available for AVE+AXI and NIV+CAB. Quality of life (QoL) One RCT measured QoL using FACIT-F (score range 0 to 52; higher scores mean better QoL) and reported that the mean post-score was 9.00 points higher (9.86 lower to 27.86 higher, very low certainty) with PAZ than with SUN. Comparison data were not available for PEM+AXI, AVE+AXI, NIV+CAB, LEN+PEM, NIV+IPI, and CAB. Serious adverse events (SAEs) Across risk groups, PEM+AXI probably increases slightly the risk for SAEs (RR 1.29, 95% CI 0.90 to 1.85, moderate certainty) compared to SUN. LEN+PEM (RR 1.52, 95% CI 1.06 to 2.19, moderate certainty) and NIV+IPI (RR 1.40, 95% CI 1.00 to 1.97, moderate certainty) probably increase the risk for SAEs, compared to SUN, respectively. There is probably little or no difference in the risk for SAEs between PAZ and SUN (RR 0.99, 95% CI 0.75 to 1.31, moderate certainty). We are uncertain whether CAB reduces or increases the risk for SAEs (RR 0.92, 95% CI 0.60 to 1.43, very low certainty) when compared to SUN. People have a mean risk of 40% for experiencing SAEs when treated with SUN. The risk increases probably to: 61% with LEN+PEM, 57% with NIV+IPI, and 52% with PEM+AXI. It probably remains at 40% with PAZ. We are uncertain whether the risk reduces to 37% with CAB. Comparison data were not available for AVE+AXI and NIV+CAB.

AUTHORS' CONCLUSIONS

Findings concerning the main treatments of interest comes from direct evidence of one trial only, thus results should be interpreted with caution. More trials are needed where these interventions and combinations are compared head-to-head, rather than just to SUN. Moreover, assessing the effect of immunotherapies and targeted therapies on different subgroups is essential and studies should focus on assessing and reporting relevant subgroup data. The evidence in this review mostly applies to advanced clear cell RCC.

Th1 polarization in the tumor microenvironment upregulates the myeloid-derived suppressor-like function of macrophages

Here, we investigated the effect of Th1 polarization in the tumor microenvironment (TME) on tumor-associated macrophage (TAM) maturation and activation. In our immunotherapy mouse model, with a Th1-dominant TME, tumors regressed in all cases, with complete regression in 80% of the cases. Monocyte-derived dendritic cells and activated CD4⁺ and CD8⁺T-cells increased in the tumor-draining lymph node, and correlated with each other in the therapeutic model. However, the cytotoxicity of tumor-infiltrating CD8⁺T-cells was slightly inhibited, whereas the number of T-cells significantly increased. Moreover, the number of TAMs increased; their maturation was inhibited; and nitrotyrosine (NT) production, as well as iNOS and arginase I expression, was increased, suggestive of the myeloid-derived suppressor cell-like immunosuppressive function of TAMs. IFN-γ knockout in the therapeutic model decreased NT production and induced macrophage maturation. Hence, Th1 polarization in the IFN-γ-dominant condition induces T-cell immune responses; however, it also enhances the immunosuppressive activity of TAMs.

Treatment of Advanced Melanoma: Past, Present and Future

Therapeutic options for treating advanced melanoma are progressing rapidly. Until six years ago, the regimen for treating advanced melanoma mainly comprised cytotoxic agents such as dacarbazine, and type I interferons. Since 2014, anti-programmed cell death 1 (PD1) antibodies have become recognized as anchor drugs for treating advanced melanoma with or without additional combination drugs such as ipilimumab. In addition, v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) kinase inhibitors in combination with mitogen-activated protein kinase kinase (MEK) inhibitors are among the most promising chemotherapeutic regimens for treating advanced BRAF-mutant melanoma, especially in patients with low tumor burden. Since anti-PD1 antibodies are widely applicable for the treatment of both BRAF wild-type and mutated advanced melanomas, several clinical trials for drugs in combination with anti-PD1 antibodies are ongoing. This review focuses on the development of the anti-melanoma therapies available today, and discusses the clinical trials of novel regimens for the treatment of advanced melanoma.

The VE-PTP Inhibitor AKB-9778 Improves Antitumor Activity and Diminishes the Toxicity of Interleukin 2 (IL-2) Administration

Administration of interleukin (IL)-2 has led to a durable response in patients with advanced renal cancer and melanoma but is restricted for clinical application because of adverse effects, including the vascular leak syndrome (VLS). VLS is associated with increased circulating levels of the Tie2 antagonist ligand, angiopoietin 2, and decreased Tie2 receptor phosphorylation and downstream signaling in endothelial cells (ECs). Given that vascular endothelial protein tyrosine phosphatase (VE-PTP) is a specific membrane phosphatase in ECs that dephosphorylates Tie2, the effects of targeting VE-PTP by a selective inhibitor AKB-9778 (AKB) in terms of VLS and antitumor efficacy were examined in this study. The authors found, by targeting VE-PTP, that the antitumor effects induced by IL-2 were augmented [tumor-free 44% (IL-2 alone) vs. 87.5% (IL-2+AKB)], associated with enhanced immune cell infiltrate (90% increase for CD8 T cells and natural killer cells). In addition, the side effects of IL-2 therapy were lessened, as demonstrated by diminished lung weight (less vascular leakage) as well as reduced cytokine levels (serum HMGB1 from 137.04±2.69 to 43.86±3.65 pg/mL; interferon-γ from 590.52±90.52 to 31.37±1.14 pg/mL). The authors further sought to determine the potential mechanism of the action of AKB-9778. The findings suggest that AKB-9778 may function through reducing serum angiopoietin 2 level and regulating EC viability. These findings provide insights into the targeting VE-PTP to improve tolerance and efficacy of IL-2 therapy and highlight the clinical potential of AKB-9778 for treating patients with VLS and cancer.

Immunotherapy for metastatic renal cell carcinoma

BACKGROUND

Since the mid-2000s, the field of metastatic renal cell carcinoma (mRCC) has experienced a paradigm shift from non-specific therapy with broad-acting cytokines to specific regimens, which directly target the cancer, the tumour microenvironment, or both.Current guidelines recommend targeted therapies with agents such as sunitinib, pazopanib or temsirolimus (for people with poor prognosis) as the standard of care for first-line treatment of people with mRCC and mention non-specific cytokines as an alternative option for selected patients.In November 2015, nivolumab, a checkpoint inhibitor directed against programmed death-1 (PD-1), was approved as the first specific immunotherapeutic agent as second-line therapy in previously treated mRCC patients.

OBJECTIVES

To assess the effects of immunotherapies either alone or in combination with standard targeted therapies for the treatment of metastatic renal cell carcinoma and their efficacy to maximize patient benefit.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE (Ovid), Embase (Ovid), ISI Web of Science and registers of ongoing clinical trials in November 2016 without language restrictions. We scanned reference lists and contacted experts in the field to obtain further information.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs with or without blinding involving people with mRCC.

DATA COLLECTION AND ANALYSIS

We collected and analyzed studies according to the published protocol. Summary statistics for the primary endpoints were risk ratios (RRs) and mean differences (MD) with their 95% confidence intervals (CIs). We rated the quality of evidence using GRADE methodology and summarized the quality and magnitude of relative and absolute effects for each primary outcome in our 'Summary of findings' tables.

MAIN RESULTS

We identified eight studies with 4732 eligible participants and an additional 13 ongoing studies. We categorized studies into comparisons, all against standard therapy accordingly as first-line (five comparisons) or second-line therapy (one comparison) for mRCC.Interferon (IFN)-α monotherapy probably increases one-year overall mortality compared to standard targeted therapies with temsirolimus or sunitinib (RR 1.30, 95% CI 1.13 to 1.51; 2 studies; 1166 participants; moderate-quality evidence), may lead to similar quality of life (QoL) (e.g. MD -5.58 points, 95% CI -7.25 to -3.91 for Functional Assessment of Cancer - General (FACT-G); 1 study; 730 participants; low-quality evidence) and may slightly increase the incidence of adverse events (AEs) grade 3 or greater (RR 1.17, 95% CI 1.03 to 1.32; 1 study; 408 participants; low-quality evidence).There is probably no difference between IFN-α plus temsirolimus and temsirolimus alone for one-year overall mortality (RR 1.13, 95% CI 0.95 to 1.34; 1 study; 419 participants; moderate-quality evidence), but the incidence of AEs of 3 or greater may be increased (RR 1.30, 95% CI 1.17 to 1.45; 1 study; 416 participants; low-quality evidence). There was no information on QoL.IFN-α alone may slightly increase one-year overall mortality compared to IFN-α plus bevacizumab (RR 1.17, 95% CI 1.00 to 1.36; 2 studies; 1381 participants; low-quality evidence). This effect is probably accompanied by a lower incidence of AEs of grade 3 or greater (RR 0.77, 95% CI 0.71 to 0.84; 2 studies; 1350 participants; moderate-quality evidence). QoL could not be evaluated due to insufficient data.Treatment with IFN-α plus bevacizumab or standard targeted therapy (sunitinib) may lead to similar one-year overall mortality (RR 0.37, 95% CI 0.13 to 1.08; 1 study; 83 participants; low-quality evidence) and AEs of grade 3 or greater (RR 1.18, 95% CI 0.85 to 1.62; 1 study; 82 participants; low-quality evidence). QoL could not be evaluated due to insufficient data.Treatment with vaccines (e.g. MVA-5T4 or IMA901) or standard therapy may lead to similar one-year overall mortality (RR 1.10, 95% CI 0.91 to 1.32; low-quality evidence) and AEs of grade 3 or greater (RR 1.16, 95% CI 0.97 to 1.39; 2 studies; 1065 participants; low-quality evidence). QoL could not be evaluated due to insufficient data.In previously treated patients, targeted immunotherapy (nivolumab) probably reduces one-year overall mortality compared to standard targeted therapy with everolimus (RR 0.70, 95% CI 0.56 to 0.87; 1 study; 821 participants; moderate-quality evidence), probably improves QoL (e.g. RR 1.51, 95% CI 1.28 to 1.78 for clinically relevant improvement of the FACT-Kidney Symptom Index Disease Related Symptoms (FKSI-DRS); 1 study, 704 participants; moderate-quality evidence) and probably reduces the incidence of AEs grade 3 or greater (RR 0.51, 95% CI 0.40 to 0.65; 1 study; 803 participants; moderate-quality evidence).

AUTHORS' CONCLUSIONS

Evidence of moderate quality demonstrates that IFN-α monotherapy increases mortality compared to standard targeted therapies alone, whereas there is no difference if IFN is combined with standard targeted therapies. Evidence of low quality demonstrates that QoL is worse with IFN alone and that severe AEs are increased with IFN alone or in combination. There is low-quality evidence that IFN-α alone increases mortality but moderate-quality evidence on decreased AEs compared to IFN-α plus bevacizumab. Low-quality evidence shows no difference for IFN-α plus bevacizumab compared to sunitinib with respect to mortality and severe AEs. Low-quality evidence demonstrates no difference of vaccine treatment compared to standard targeted therapies in mortality and AEs, whereas there is moderate-quality evidence that targeted immunotherapies reduce mortality and AEs and improve QoL.

WITHDRAWN: Immunotherapy for advanced renal cell cancer

This review is being updated and replaced following the publication of a new protocol (Unverzagt S, Moldenhauer I, Coppin C, Greco F, Seliger B. Immunotherapy for metastatic renal cell carcinoma [Protocol]. Cochrane Database of Systematic Reviews 2015, Issue 4. Art. No.: CD011673. DOI: 10.1002/14651858.CD011673). It will remain withdrawn when the new review is published.

The editorial group responsible for this previously published document have withdrawn it from publication.

Toxicities of Immunotherapy for the Practitioner

The toxicities of immunotherapy for cancer are as diverse as the type of treatments that have been devised. These range from cytokine therapies that induce capillary leakage to vaccines associated with low levels of autoimmunity to cell therapies that can induce damaging cross-reactivity with normal tissue to checkpoint protein inhibitors that induce immune-related adverse events that are autoinflammatory in nature. The thread that ties these toxicities together is their mechanism-based immune nature and the T-cell-mediated adverse events seen. The basis for the majority of these adverse events is a hyperactivated T-cell response with reactivity directed against normal tissue, resulting in the generation of high levels of CD4 T-helper cell cytokines or increased migration of cytolytic CD8 T cells within normal tissues. The T-cell immune response is not tissue specific and may reflect a diffuse expansion of the T-cell repertoire that induces cross-reactivity with normal tissue, effectively breaking tolerance that is active with cytokines, vaccines, and checkpoint protein inhibitors and passive in the case of adoptive cell therapy. Cytokines seem to generate diffuse and nonspecific T-cell reactivity, whereas checkpoint protein inhibition, vaccines, and adoptive cell therapy seem to activate more specific T cells that interact directly with normal tissues, potentially causing specific organ damage. In this review, we summarize the toxicities that are unique to immunotherapies, emphasizing the need to familiarize the oncology practitioner with the spectrum of adverse events seen with newly approved and emerging modalities.

Systematic review and network meta-analysis of overall survival comparing 3 mg/kg ipilimumab with alternative therapies in the management of pretreated patients with unresectable stage III or IV melanoma

OBJECTIVE

To compare the overall survival (OS) of patients treated with 3 mg/kg ipilimumab versus alternative systemic therapies in pretreated unresectable stage III or IV melanoma patients.

METHODS

A systematic literature search was performed to identify relevant randomized clinical trials. From these trials, Kaplan-Meier survival curves for each intervention were digitized and combined by means of a Bayesian network meta-analysis (NMA) to compare different drug classes.

RESULTS

Of 38 trials identified, 15 formed one interlinked network by drug class to allow for an NMA. Ipilimumab, at a dose of 3 mg/kg, was associated with a greater mean OS time (18.8 months; 95% credible interval [CrI], 15.5-23.0 months) than single-agent chemotherapy (12.3 months; 95% CrI, 6.3-28.0 months), chemotherapy combinations (12.2 months; 95% CrI, 7.1-23.3 months), biochemotherapies (11.9 months; 95% CrI, 7.0-22.0 months), single-agent immunotherapy (11.1 months; 95% CrI, 8.5-16.2 months), and immunotherapy combinations (14.1 months; 95% CrI, 9.0-23.8 months).

CONCLUSION

Results of this NMA were in line with previous findings and suggest that OS with ipilimumab is expected to be greater than with alternative systemic therapies, alone or in combination, for the management of pretreated patients with unresectable stage III or IV melanoma.

Tumour necrosis factor-alpha expression in tumour islets confers a survival advantage in non-small cell lung cancer

BACKGROUND

The role of TNFalpha in cancer is complex with both pro-tumourigenic and anti-tumourigenic roles proposed. We hypothesised that anatomical microlocalisation is critical for its function.

METHODS

This study used immunohistochemistry to investigate the expression of TNFalpha in the tumour islets and stroma with respect to survival in 133 patients with surgically resected NSCLC.

RESULTS

TNFalpha expression was increased in the tumour islets of patients with above median survival (AMS) compared to those with below median survival (BMS)(p = 0.006), but similar in the stroma of both groups. Increasing tumour islet TNFalpha density was a favorable independent prognostic indicator (p = 0.048) while stromal TNFalpha density was an independent predictor of reduced survival (p = 0.007). Patients with high TNFalpha expression (upper tertile) had a significantly higher 5-year survival compared to patients in the lower tertile (43% versus 22%, p = 0.01). In patients with AMS, 100% of TNFalpha+ cells were macrophages and mast cells, compared to only 28% in the islets and 50% in the stroma of BMS patients (p < 0.001).

CONCLUSIONS

The expression of TNFalpha in the tumour islets of patients with NSCLC is associated with improved survival suggesting a role in the host anti-tumour immunological response. The expression of TNFalpha by macrophages and mast cells is critical for this relationship.

Synergism of hydroxyapatite nanoparticles and recombinant mutant human tumour necrosis factor-alpha in chemotherapy of multidrug-resistant hepatocellular carcinoma

BACKGROUND/AIMS

Locoregional chemotherapy continues to be the mainstay for the treatment of unresectable hepatocellular carcinoma (HCC). One of the principal obstacles implicated in its unsuccessful therapy is multidrug resistance (MDR). Former studies have identified the multidrug-resistant nature and possible mechanisms of hepatoma cells both in vitro and in vivo. This work aimed to develop an effective strategy for the treatment of HCC with MDR.

METHODS

The treatment was exploited to inhibit the MDR cells by co-administration of the recombinant mutant human tumour necrosis factor-alpha (rmhTNF-alpha), a sublethal dose of chemicals [adriamycin (ADM), mitomycin and 5-FU] and hydroxyapatite nanoparticles (nHAPs). Real-time quantitative reverse transcriptase-polymerase chain reaction and electrochemiluminescence Western blot were used to detect the expression of several related genes.

RESULTS

The chemicals acted synergistically with rmhTNF-alpha and nHAP in suppressing the growth of hepatoma cells and inducing apoptosis of the cells, with the MDR phenotype reversed, as measured by intracellular ADM retention. Analysis of mRNA and protein revealed that rmhTNF-alpha inhibited the gene expression of XIAP, survivin, Ki67, PCNA, MDR1 and BCRP to some extent. Moreover, the inhibitory effects mentioned above could be as good or better than when nHAP is incorporated into the regimens.

CONCLUSIONS

rmhTNF-alpha was not only able to restore the chemotherapeutic sensitivity to HepG2/ADM, its xenograft model and clinical samples but also further inhibited the growth of these tumours by a combination of nHAP. These results strongly suggested that chemicals in combination with rmhTNF-alpha and nHAP may be beneficial for the local treatment of advanced HCC.

Pharmacologic administration of interleukin-2

The development of biologic therapies for patients with cancer has in part been impeded by the extraordinary complexity and intrinsic feedback mechanisms promoting homeostasis in tissue injury, repair, inflammation, and immunity. Recombinant interleukin 2 (IL-2) therapy was initiated in 1984 based on its role as the prototypic T-cell growth factor, with novel roles deduced late after its FDA approval in regulating not only effector T cells but also regulatory T cells. Complicating its application, even in the most sophisticated centers, has been the manageable but difficult toxicities attendant on its use in spite of clear evidence of complete responses in 5-10% of treated patients with melanoma and renal cell carcinoma with extraordinary durability lasting now for almost 25 years, thus tantamount to "cures." Although efforts have been made to diminish toxicity or enhance efficacy the only substantive advance in combination therapy has been the application of tumor-infiltrating lymphocytes and the antibody to CTLA4. A deeper understanding of the "limiting" toxicity associated with mild flu-like symptoms and more debilitating cytokine "storm" not forthcoming. Here we propose the notion that the systemic syndrome associated with IL-2 administration is due to global cytokine-induced autophagy and temporally limited tissue dysfunction. The possible role of autophagy inhibitors to enhance efficacy and limit toxicity as well as possible problems with this approach are considered.

Angiopoietin 2 Is a Potential Mediator of High-Dose Interleukin 2–Induced Vascular Leak

PURPOSE

High-dose interleukin 2 (HDIL2) produces durable tumor regressions in 10% of patients with metastatic renal cell carcinoma and melanoma. However, a major toxicity is vascular leak syndrome (VLS). We previously reported elevated serum angiopoietin 2 (Ang2) in septic patients with vascular leak and hypothesized that Ang2 might also contribute to HDIL2 VLS.

EXPERIMENTAL DESIGN

Blood was collected from 14 patients receiving HDIL2 and from 4 patients receiving HDIL2 and bevacizumab, an antibody against vascular endothelial growth factor (VEGF). The effect of Ang2 was studied in vitro by incubating high Ang2 patient serum with cultured endothelial cells.

RESULTS

Pretreatment Ang2 levels were in the reference range (median, 3.3 ng/mL) and rose with each day of IL-2 therapy (median peak, 29.7 ng/mL). No trend was seen in free VEGF levels during therapy. Patients treated with HDIL2 and bevacizumab all developed VLS and elevated Ang2. High Ang2 patient sera induced propermeability structural changes in endothelial cells, an effect reversed by blockade with the competitive ligand angiopoietin 1 (Ang1).

CONCLUSIONS

Ang2 may be a mediator of HDIL2 VLS as evidenced by (a) an increase in Ang2 in all patients on HDIL2; (b) the effect of high Ang2 patient serum on cultured endothelial cells; (c) rescue of those structural changes by Ang1. The lack of correlation between VLS and serum VEGF levels in patients treated with HDIL2 alone or in combination with bevacizumab suggests that VEGF is not a major contributor to VLS or Ang2 release. These data suggest that the inhibition of Ang2 may mitigate VLS in patients receiving HDIL2.

Role of Cytokine Therapy in 2006 and Beyond for Metastatic Renal Cell Cancer

Metastatic renal cell cancer (mRCC) has a long history as a disease with poor prognosis and limited therapeutic options. Immunotherapy has been the mainstay of treatment since the 1980s, and there have been a number of largely phase II studies examining various schedules of interferon-alpha and interleukin-2 based treatments. With the development of molecular targeted drugs the armentarium against mRCC has significantly expanded and cytokine treatments should be only directed at those most likely to benefit with durable remissions and prolonged survival.

Therapeutic potential of cytokine and chemokine antagonists in cancer therapy

A new paradigm is becoming widely accepted, that chronic inflammation, driven in part by chemokines and cytokines at the site of a tumour, may facilitate tumour progression instead of promoting anti-tumour immunity. Tumours and activated stromal cells secrete pro-inflammatory chemokines and cytokines that act either directly or indirectly through stimulation of the vascular endothelium to recruit leukocytes to the tumour. After activation, these tumour-associated leukocytes release angiogenic factors, mitogens, proteolytic enzymes, and chemotactic factors, recruiting more inflammatory cells and stimulating angiogenesis to sustain tumour growth and facilitate tumour metastasis. Breaking this cycle by inhibiting targets such as cytokines, chemokines and other inflammatory mediators, either alone, or more realistically, in combination with other therapies, such as anti-angiogenic or cytotoxic agents, may provide highly efficacious therapeutic regimens for the treatment of malignancies. This article reviews anti-cytokine and anti-chemokine therapies being pursued in cancer, and discusses in more detail anti-tumour necrosis factor-alpha (TNF) approaches.

Interleukin-2 in the treatment of malignant melanoma

Interleukin-2 (IL-2) is a lymphokine produced by T-cells that has a number of immunomodulatory effects. Treatment of metastatic melanoma with recombinant interleukin-2 (rIL-2)-based therapies represents one of the earliest attempts at systemic immunomodulation as a therapy for cancer. Initial studies showed objective response rates with rIL-2 therapy alone in the range of 15 - 20% with some durable responses. A multitude of studies have been undertaken with various rIL-2 regimens, with and without co-administration of lymphokine-activated cells or tumour-infiltrating lymphocytes. However, the optimum dose and treatment schedule for rIL-2-based therapy in metastatic melanoma, remains controversial. There are also no clear immunological parameters that can reliably predict antitumour response to rIL-2-based therapy. Ongoing research remains active in exploring the role of rIL-2 in the therapy of malignant melanoma (MM), particularly in conjunction with cytotoxic therapy.

Immunotherapy for advanced renal cell cancer

BACKGROUND

The course of advanced renal cell carcinoma is extremely variable, ranging from spontaneous remission to disease progression refractory to chemotherapy. Immunotherapy has held promise of improved outcomes based on uncontrolled studies and randomized controlled trials generally limited by small size and low power.

OBJECTIVES

To evaluate immunotherapy for advanced renal cell carcinoma by comparing: (1) high dose interleukin-2 to other options and (2) interferon-alfa to other options. The primary outcome of interest was overall survival at one year, with remission as the main secondary outcome of interest.

SEARCH STRATEGY

A systematic search of the CENTRAL, MEDLINE, and EMBASE databases was conducted for the period 1966 through end of December 2003. Handsearches were made of the proceedings of the periodic meetings of the American Urologic Association, the American Society of Clinical Oncology, ECCO - the European Cancer Conference, and the European Society of Medical Oncology for the period 1995 to June 2004.

SELECTION CRITERIA

Randomized controlled trials that selected (or stratified) patients with advanced renal cell carcinoma, utilized an immunotherapeutic agent in at least one study arm, and reported remission or survival by allocation. Fifty-three identified studies involving 6117 patients were eligible and all but one reported remission; 32 of these studies reported the one-year survival outcome.

DATA COLLECTION AND ANALYSIS

Two reviewers independently abstracted each article by following a prospectively designed protocol. Dichotomous outcomes for treatment remission (partial plus complete) and for deaths at one year were used for the main comparisons. Survival hazard ratios were also used for studies of interferon-alfa versus controls, and for two randomized studies of the value of initial nephrectomy prior to interferon-alfa in fit patients with metastases detected at the time of diagnosis.

MAIN RESULTS

Combined data for a variety of immunotherapies gave an overall chance of partial or complete remission of only 12.9% (99 study arms), compared to 2.5% in 10 non-immunotherapy control arms, and 4.3% in two placebo arms. Twenty-eight percent of these remissions were designated as complete (data from 45 studies). Median survival averaged 13.3 months (range by arm, 6 to 27+ months). The difference in remission rate between arms was poorly correlated with the difference in median survival so that remission rate is not a good surrogate or intermediate outcome for survival for advanced renal cancer. We were unable to identify any published randomized study of high-dose interleukin-2 versus a non-immunotherapy control, or of high-dose interleukin-2 versus interferon-alfa reporting survival. It has been established that reduced dose interleukin-2 given by intravenous bolus or by subcutaneous injection provides equivalent survival to high dose interleukin-2 with less toxicity. Results from four studies (644 patients) indicate that interferon-alfa is superior to controls (OR for death at one year = 0.56, 95% confidence interval 0.40 to 0.77). Using the method of Parmar 1998, the pooled overall hazard ratio for death was 0.74 (95% confidence interval 0.63 to 0.88). The weighted average median improvement in survival was 3.8 months. T he optimal dose and duration of interferon-alfa remains to be elucidated. The addition of a variety of enhancers, including lower dose intravenous or subcutaneous interleukin-2, has failed to improve survival compared to interferon-alfa alone. Two recent randomized studies have examined the role of initial nephrectomy prior to interferon-alfa therapy in highly selected fit patients with metastases at diagnosis and minimal symptoms: despite minimal improvement in the chance of remission, both studies of up-front nephrectomy improved median survival by 4.8 months over interferon-alfa alone. Recent studies have been examining anti-angiogenesis agents. A landmark study of bevacizumab, an anti-vascular endothelial growth factor antibody, was associated with significant prolongation of the time to progression of disease when given at high dose compared to low-dose or placebo therapy though frequency of remissions or survival were not improved.

AUTHORS' CONCLUSIONS

interferon-alfa provides a modest survival benefit compared to other commonly used treatments and should be considered for the control arm of future studies of systemic agents. In fit patients with metastases at diagnosis and minimal symptoms, nephrectomy followed by interferon-alfa gives the best survival strategy for fully validated therapies. The need for more effective specific therapy for this condition is apparent.

Application of IL-2 and other cytokines in renal cancer

Renal cell carcinoma evokes an immune response, which investigators have attempted to augment by administering cytokines in doses above physiological levels. In 1992, high-dose (HD) bolus interleukin-2 (IL-2) received US Food and Drug Administration approval for metastatic renal cell carcinoma based on data that revealed durable responses in a small percentage of patients. However, this regimen is associated with significant toxicity and cost, which has limited its application to highly selected patients treated at specialised centres. Several investigators have evaluated regimens with lower doses of IL-2 in an attempt to decrease toxicity. Attempts were also made to improve treatment efficacy by adding interferon (IFN)-alpha followed by 5-fluorouracil to low-dose IL-2 regimens. These regimens were reported to produce response rates and survival comparable to HD IL-2 with much less toxicity, but possibly fewer durable responses. Based on positive preclinical data, other cytokines (e.g., IFN-gamma, IL-12) have also been given to patients with metastatic renal cell carcinoma with limited success. This review examines the clinical trials that have described the efficacy and toxicity of IL-2 and other cytokines in patients with renal cancer, with a particular focus on the Phase III trials that have helped to define the proper use of these agents.

A systematic review of the relation between interleukin-2 schedule and outcome in patients with metastatic renal cell cancer

In Europe, interleukin 2 (IL-2) is one of the two treatment modalities officially approved for patients with metastatic renal cell cancer. Traditionally, IL-2 has been administered by three different routes: intermittent bolus injection (BIV), continuous intravenous infusion (CIV) and subcutaneous injection (SC). There have been few randomized trials designed to compare these routes of administration. This paper describes a systematic review of the literature in which an attempt has been made to determine which schedule of administration is superior. Heterogeneity of the data makes firm conclusions difficult. It appears that the number of complete remissions (CR) is similar between BIV and SC routes and that these are higher than for CIV schedules. The durability of the CRs induced by BIV appeared superior to those induced by SC IL-2 and definitely higher than with CIV protocols. This analysis highlights some of the difficulties of using evidence-based medicine to determine standard of care when the clinical-trial data are heterogeneous. These data emphasize the importance of randomized clinical trials in determining what should be regarded as optimum therapy.

Immune effects of escalating doses of granulocyte-macrophage colony-stimulating factor added to a fixed, low-dose, inpatient interleukin-2 regimen: a randomized phase I trial in patients with metastatic melanoma and renal cell carcinoma

Previous studies in cancer patients demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) upregulated the interleukin (IL)-2 receptor on T lymphocytes and monocytes suggesting that subsequently administered IL-2 would produce greater immune effects. The authors treated 21 patients with metastatic renal cell carcinoma and melanoma on a randomized phase I study to test this hypothesis. All 21 patients received a fixed dose of IL-2 (72,000 IU/kg every 8 hours for 5 days) administered intravenously as an inpatient. Patients were randomized to receive IL-2 alone or in combination with GM-CSF at a dose of 125 or 250 mcg/m /d (Sargramostim; Immunex Corporation, WA, U.S.A.) daily for 7 days by subcutaneous injection starting on day 1, the day before IL-2 treatment. The results from this study demonstrated that GM-CSF did not worsen the toxicities produced by IL-2 alone. Grade 3 confusion occurred in four patients, three who received IL-2 alone. No partial or complete tumor responses were seen. Assays of serum soluble IL-2 receptor (sIL2R) and neopterin, measures of T cell and monocyte activation, respectively, demonstrated a significant increase in sIL2R but not neopterin, 24 hours after the first dose of GM-CSF. In combination with IL-2, the higher dose of GM-CSF (250 mcg/m ) produced higher sIL2R levels on days 3 and 7 than the 125-mcg/m dose of GM-CSF or IL-2 alone. Although neopterin levels did not increase after 1 day of GM-CSF, the addition of IL-2 resulted in a significantly increased neopterin level on day 3 at the higher dose of GM-CSF. On day 7, neopterin levels in all three groups were similarly increased over baseline. Ten days after treatment, neopterin levels had returned to normal, but sIL2R levels remained markedly increased (12 fold) over baseline in the higher GM-CSF dose group. The authors conclude that 1) monocyte activation was not significantly enhanced by 1 day of GM-CSF treatment; 2) the 250-mcg/m GM-CSF dose plus IL-2 produced superior T cell activation compared with a lower dose of GM-CSF plus IL-2 or to IL-2 alone; and 3) the combination of GM-CSF and IL-2 was safe and tolerable but was not associated with any clinical responses.

Effect of etanercept (Enbrel) on interleukin 6, tumor necrosis factor alpha, and markers of immune activation in HIV-infected subjects receiving interleukin 2

The effect of etanercept, a soluble p75 tumor necrosis factor (TNF) receptor:Fc fusion protein (Enbrel; Immunex, Seattle, WA) on plasma cytokines was evaluated in 11 HIV-infected subjects receiving highly active antiretroviral therapy (HAART) for 28 weeks with or without subcutaneous or intravenous recombinant human interleukin 2 (rhIL-2). Plasma IL-6 and C-reactive protein (CRP) levels increased after rhIL-2 treatment. Etanercept pretreatment attenuated these increases. Median plasma IL-6 levels were 20.29 pg/ml 4 days after rhIL-2 and 7.87 pg/ml 4 days after etanercept and rhIL-2 (p = 0.22); median CRP levels were 78.73 and 46.16 microg/ml, respectively (p = 0.03). An effect on TNF bioactivity could not be assessed as all measurements were below limits of detection. No significant changes were seen in temperature or plasma levels of IL-4, IL-10, IL-12, interferon gamma, or HIV-1 RNA levels. All subjects had undetectable or low-level HIV-1 RNA levels before etanercept dosing. One subject died; however, her death was thought to be unrelated to etanercept. Pretreatment with etanercept may blunt activation of IL-6 and CRP expression induced by rhIL-2. The safety and utility of etanercept in HIV-infected persons should be explored further.

The biological treatment of renal-cell carcinoma and melanoma

Biological therapies are claiming a place in the routine management of some solid tumours. In this review we focus on the biological treatment of melanoma and renal-cell carcinoma, identifying the background to current practice and areas of promise that may be in routine clinical use in the near future. Melanomas and renal-cell carcinomas are particularly resistant to chemotherapy and radiotherapy and are characterised by the host immune response to the tumours. For this reason there has been particular interest in the biological therapy of these diseases. Biological therapies differ from chemotherapeutic approaches in their mechanism of action, time to response, and side-effect profiles. Although biological treatment has a long history, it is only with recent advances in immunology and molecular biology that progress has been made. In the next few years investigators expect to build on their research experience with biotherapeutic agents to provide tangible benefits for patients.

[Value of anti-TNF-alpha molecules in inflammatory and infectious diseases]

INTRODUCTION

The pathophysiological interest of tumor necrosis factor-alpha (TNF-alpha) has been recently reported in inflammatory and infectious diseases. Thus, TNF-alpha blockade has become a new field of therapeutical research.

CURRENT KNOWLEDGE AND KEY POINTS

Several biological agents specifically directed against TNF-alpha are available: anti-TNF-alpha monoclonal antibodies on the one hand--either mainly murine sequence (cA2), partially humanized (CDP 571) or fully human (D2E7)--and TNF-alpha soluble receptors on the other hand (lenercept or etanercept). The first clinical studies reveal interesting results. In rheumatoid arthritis (cA2, etanercept), these molecules may be used either alone or in synergistic combination with methotrexate. They produce a significant response compared to placebo or methotrexate alone, without loss of efficacy in medium-term treatment. In Crohn's disease (cA2 CDP571), they reduce significantly the activity of the disease, compared to placebo, and cA2 makes it possible to accelerate closure of the fistulas. The studies of severe sepsis did not reveal a significant efficacy, however, and only one study has been published on malignant disease, with a possible interesting effect. Even if these medications are usually well tolerated, the frequency of infections is slightly increased. The development of anti-DNA antibodies has also been reported, but drug-induced lupus is highly unusual.

FUTURE PROSPECTS AND PROJECTS

Further studies will define the place of anti-TNF-alpha biological agents among the other available treatments of rheumatoid arthritis and Crohn's disease. Because of their high cost, these drugs will probably be limited to patients with active inflammatory disease despite more conventional treatments.

Immunotherapy for advanced renal cell cancer

BACKGROUND

The course of advanced renal cell carcinoma is extremely variable, ranging from spontaneous remission to disease progression refractory to chemotherapy. Immunotherapy has held promise of improved outcomes based on uncontrolled studies and randomized controlled trials generally limited by small size and low power.

OBJECTIVES

To evaluate immunotherapy for advanced renal cell carcinoma by comparing: (1) high dose interleukin-2 to other options and (2) interferon-alpha to other options.

SEARCH STRATEGY

A search of MEDLINE, Cancerlit, EMBASE and Cochrane Library databases from 1966 through the end of 1999. Handsearches were made of the proceedings of the annual meetings of the American Urologic Association, ASCO, and biennial European ECCO meetings, and the references of identified studies.

SELECTION CRITERIA

Randomized controlled trials that selected (or stratified) patients with advanced renal cell carcinoma, utilized an immunotherapeutic agent in at least one study arm, and reported response or survival by allocation. Forty-two studies involving 4216 patients were eligible and reported response and 26 of these reported survival outcome (3089 patients).

DATA COLLECTION AND ANALYSIS

Two independent reviewers abstracted each article by following a prospectively designed protocol. Dichotomous outcomes for treatment response (partial plus complete) and for deaths at one year were used for the main comparisons. Survival hazard ratios were also used for studies of interferon-alpha versus controls.

MAIN RESULTS

The average response rate was 10.2 % (range by arm, 0 - 39%) and complete response rate was 3.2% (123/3852; n = 38 studies). Median survival averaged 11.6 months (range by arm, 6 - 28 months) and two-year survival averaged 22% (16 studies, range by arm 8 - 41%). There were no placebo-controlled studies and no randomized controlled studies examined survival for high dose interleukin-2 versus controls. Results from 6 studies (n = 963) indicate that interferon-alpha is superior to controls (OR for death at one year = 0.67, 95% CI 0.50 - 0.89. The pooled hazard ratio for survival of 0.78 (0.67 - 0.90) indicates that the treatment effect persisted until 24 months from randomization. The weighted average median improvement in survival was 2.6 months. Additional comparisons failed to prove a survival benefit from the addition of other agents to either modified schedules of interleukin-2 or to interferon-alpha. Dose-response studies examining survival for either agent could not be identified. The difference in response rate between arms was correlated with the difference in survival (P<0.001) suggesting that response rate difference may be a surrogate intermediate endpoint for survival.

REVIEWER'S CONCLUSIONS

Interferon-alpha provides a modest survival benefit compared to other commonly used treatments and should be considered for the control arm of future studies of systemic agents. Interleukin-2 has not been validated in controlled randomized studies.

High-dose recombinant interleukin 2 therapy for patients with metastatic melanoma: analysis of 270 patients treated between 1985 and 1993

PURPOSE

To determine the short- and long-term efficacy and toxicity of the high-dose intravenous bolus interleukin 2 (IL-2) regimen in patients with metastatic melanoma.

PATIENTS AND METHODS

Two hundred seventy assessable patients were entered onto eight clinical trials conducted between 1985 and 1993. IL-2 (Proleukin [aldesleukin]; Chiron Corp, Emeryville, CA) 600,000 or 720,000 IU/kg was administered by 15-minute intravenous infusion every 8 hours for up to 14 consecutive doses over 5 days as clinically tolerated with maximum support, including pressors. A second identical treatment cycle was scheduled after 6 to 9 days of rest, and courses could be repeated every 6 to 12 weeks in stable or responding patients. Data were analyzed through fall 1996.

RESULTS

The overall objective response rate was 16% (95% confidence interval, 12% to 21%); there were 17 complete responses (CRs) (6%) and 26 partial responses (PRs) (10%). Responses occurred with all sites of disease and in patients with large tumor burdens. The median response duration for patients who achieved a CR has not been reached and was 5.9 months for those who achieved a PR. Twelve (28%) of the responding patients, including 10 (59%) of the patients who achieved a CR, remain progression-free. Disease did not progress in any patient responding for more than 30 months. Baseline performance status and whether patients had received prior systemic therapy were the only predictive prognostic factors for response to IL-2 therapy. Toxicities, although severe, generally reversed rapidly after therapy was completed. Six patients (2%) died from adverse events, all related to sepsis.

CONCLUSION

High-dose IL-2 treatment seems to benefit some patients with metastatic melanoma by producing durable CRs or PRs and should be considered for appropriately selected melanoma patients.

Treatment of malignant melanoma

OBJECTIVE

To review the current treatments for cutaneous melanoma and discuss treatment approaches for each patient population.

DATA SOURCES

MEDLINE and IOWA database search from January 1990 to December 1998.

DATA EXTRACTION

Clinical trials and review articles were selected and classified to answer questions considered of clinical relevance.

RESULTS

Patients with stage I, II, and III melanoma should undergo excision after biopsy. In patients with stage IV melanoma, surgical excision of metastatic melanoma is not considered curative but can provide palliation and improve quality of life. Therapeutic lymph node dissection should be performed in patients with melanoma in stages III and IV once pathologic confirmation is obtained. Patients at high risk for recurrence or metastasis may also be considered for elective node dissection. Adjuvant therapy after surgery excision is not a standard of care in patients with stage I and IIa melanoma. In patients with stage IIb and III melanoma, the best results have been obtained with high doses of interferon alfa-2b, although toxicity is of concern. Isolated limb perfusion with melphalan adjuvant to surgery has demonstrated clinically significant benefit in patients with locally recurrent melanoma and in-transit metastases. Studies comparing efficacy and quality of life with this technique or with high doses of interferon alfa-2b are needed. The technique cannot be recommended for high-risk primary melanoma of an extremity with no clinical evidence of metastatic disease.

CONCLUSIONS

To date, dacarbazine still appears to be the treatment of first choice in metastatic melanoma, outside of a clinical trial. The combination of chemotherapy with interferon alfa-2b or interferon alfa-2a enhances toxicity without a significant survival advantage. Aldesleukin may be an alternative in selected patients when other treatments have failed, but the higher toxicity and cost must be considered.

Etanercept

Each month, subscribers to The Formulary® Monograph Service receive five to six researched monographs on drugs that are newly released or are in late Phase III trials. The monographs are targeted to your Pharmacy and Therapeutics Committee. Subscribers also receive monthly one-page summary monographs on the agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation (DUE) is also provided each month. The monographs are published in printed form and on diskettes that allow customization. Subscribers to the The Formulary Monograph Service also receive access to a pharmacy bulletin board called The Formulary Information Exchange (The F.I.X). All topics pertinent to clinical pharmacy are discussed on The F.I.X.

Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. If you would like information about The Formulary Monograph Service or The F.I.X., call The Formulary at 800-322-4349. The April 1999 Formulary monographs include cilostazol, altretinoin, rosiglitazone, oxcarbazepine, and rabeprazole. The DUE is on cilostazol.

Clinical applications of TNF-alpha in cancer

High-dose TNF-alpha plus chemotherapy, with or without IFN-gamma, can be safely administered regionally through isolated limb perfusion. This procedure produced between 70% and 80% complete remission in cases of in transit melanoma metastases and between 25% and 36% complete remission in cases of inextirpable soft-tissue sarcomas. Dual targeting is involved; TNF-alpha and IFN-gamma induce apoptosis of angiogenic endothelium, while melphalan induces apoptosis of tumour cells.

Immunotherapy and experimental approaches for metastatic melanoma

This article reviews the clinical investigations involving recombinant cytokines (either alone or in combination with adoptive immunotherapy, toxicity reduction agents, or cytotoxic chemotherapy), vaccines, monoclonal antibodies or antibody conjugates, and gene therapy. These various approaches are reviewed for their current and potential roles in curing metastatic melanoma.

The tetravalent guanylhydrazone CNI-1493 blocks the toxic effects of interleukin-2 without diminishing antitumor efficacy

The use of interleukin 2 (IL-2) as an antineoplastic agent has been limited by the serious toxicities that accompany the doses necessary for a tumor response. Elevation of nitric oxide (NO) and tumor necrosis factor (TNF) both have been implicated in IL-2 toxicities. CNI-1493, a tetravalent guanylhydrazone, is an inhibitor of macrophage activation including the synthesis of TNF and other cytokines. Doses of CNI-1493 as low as 1 mg/kg/day conferred complete protection against fatal toxicity of IL-2 with IL-2 doses tenfold higher than the safely tolerated level in Sprague-Dawley rats. Moreover, typical pathologic changes in the lungs, kidneys, and the liver caused by IL-2 infusion were blocked by cotreatment with CNI-1493. When animals bearing established hepatomas were given IL-2 and CNI-1493 combination therapy, 10 of 10 hepatomas regressed from 1 cm3 to <1 mm3. Intracytoplasmic TNF levels were increased in normal tissues from IL-2 treated animals, and treatment with CNI-1493 maintained TNF at control levels. The degree of apoptosis measured by terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling staining of tumors following IL-2 therapy was not reduced compared with IL-2 cotreated with CNI-1493. In contrast, apoptosis in the liver and lung parenchyma following IL-2 therapy was blocked completely by cotreatment with CNI-1493. Taken together, these data showed that low and infrequent doses of CNI-1493 markedly protected animals from IL-2 systemic toxicities whereas not affecting tumor response to IL-2 therapy. With the protection afforded by CNI-1493 treatment, IL-2 therapy dose levels could be increased to provide significant antitumor effects in animals with established hepatomas.

Natural history and therapy of metastatic renal cell carcinoma: the role of interleukin-2

BACKGROUND

Despite significant advances in understanding the biology of renal cell carcinoma (RCC) during the past decade, metastatic disease remains nearly incurable and a major medical challenge. Because RCC is known to be immunogenic, immunotherapeutic agents such as recombinant human interleukin-2 (rIL-2) and interferon-alpha (IFN-alpha) have represented encouraging treatment modalities.

METHODS

A review of the natural history of and therapeutic approaches to RCC was examined. Studies involving rIL-2 alone and in combination with other adjuvant therapies were critically evaluated.

RESULTS

Overall response rates for metastatic RCC patients treated with rIL-2 were similar (i.e., in the range of 15-20%), regardless of whether rIL-2 was administered as monotherapy or in combination with IFN-alpha. Recombinant IL-2 monotherapy response rates were similar to those of IFN-alpha, but with an increased frequency of complete responses and enhanced response duration. Subcutaneous administration generally resulted in lower toxicity than intravenous administration. The roles of chemotherapy or adoptive immunotherapy in combination with rIL-2 and IFN-alpha therapy remain unclear and require further study. The importance of patient performance status as a predictor of response and survival in rIL-2 therapy was demonstrated.

CONCLUSIONS

The use of rIL-2 with or without IFN-alpha may represent the most useful therapeutic approach currently available for patients with good performance status. In patients with borderline performance status or severe comorbid disease, therapeutic approaches depend on patient factors and outcome expectation and may involve cytokine therapy. However, regardless of performance status, palliative measures and/or observation are important choices, because the majority of patients with metastatic RCC are incurable.