Safety and efficacy of subcutaneous and continuous intravenous infusion rIL-2 in patients with metastatic renal cell carcinoma

Site-Specific Chemical Modification of a Cytokine Mimic for Small Molecule-Based Tumor Targeting

The targeted delivery of bioactive proteins, such as cytokines, for cancer immunotherapy approaches mostly relies on antibodies or antibody fragments. However, fusion proteins may display low tissue penetration due to a large molecular size. Small molecule ligands with high affinity toward tumor-associated antigens provide a promising alternative for the selective delivery of cytokines to tumor lesions. We developed a one-pot procedure for the site-specific thiazolidine formation between an aldehyde bearing small molecule and the in situ generated N-terminal cysteine of a bioactive protein. Thereby, neoleukin-2/15 (Neo-2/15), a computationally engineered interleukin-2 and -15 mimic, was chemically conjugated to acetazolamide plus, a potent carbonic anhydrase IX (CAIX) ligand. The conjugate retained the biological activity of Neo-2/15 and revealed its ability to accumulate in renal cell carcinoma (SK-RC-52) xenografts upon systemic intravenous administration. The results highlight the potential of small molecule targeting moieties to drive the accumulation of a protein cargo to the respective disease site while conserving the small construct size.

An engineered 4-1BBL fusion protein with "activity on demand"

Engineered cytokines are gaining importance in cancer therapy, but these products are often limited by toxicity, especially at early time points after intravenous administration. 4-1BB is a member of the tumor necrosis factor receptor superfamily, which has been considered as a target for therapeutic strategies with agonistic antibodies or using its cognate cytokine ligand, 4-1BBL. Here we describe the engineering of an antibody fusion protein, termed F8-4-1BBL, that does not exhibit cytokine activity in solution but regains biological activity on antigen binding. F8-4-1BBL bound specifically to its cognate antigen, the alternatively spliced EDA domain of fibronectin, and selectively localized to tumors in vivo, as evidenced by quantitative biodistribution experiments. The product promoted a potent antitumor activity in various mouse models of cancer without apparent toxicity at the doses used. F8-4-1BBL represents a prototype for antibody-cytokine fusion proteins, which conditionally display "activity on demand" properties at the site of disease on antigen binding and reduce toxicity to normal tissues.

Concomitant Drug Treatment and Elimination in the RCC-affected Kidneys: Can We Kill Two Birds with One Stone?

BACKGROUND

The kidneys are vital organs acting as the body's filters that eliminate drugs and other waste products from the body. For effective cancer therapy, a delicate balance is required in the drug treatment and its elimination, which is critical for drug accumulation, toxicity, and kidney malfunction. However, how renal cell carcinoma (RCC) affects the kidneys in safely eliminating the byproducts of drug treatments in patients with severely dysregulated kidney functions had remained elusive. Recent advancements in dose adjustment have added to our understanding regarding how drug treatments could be effectively regulated in aberrant kidney cells, driving safe elimination and reducing drug accumulation and toxicity at the right time and space. Dose adjustment is the only standard systemic way applicable; however, it presents certain limitations. There is significant room for developing new strategies and alternatives to improve it.

OBJECTIVES

Our analysis of the available treatments in literature discusses the treatment and their safe eliminations. In this study, we give an overview of the measures that could be taken to maintain the elimination gradient of anti-cancer drugs and restore normal kidney function in RCC. Differential therapeutics of RCC/mRCC in various clinical phase trials and the interaction of targeted therapeutics in response to vascular endothelial growth factor (VEGF) were also discussed.

CONCLUSION

Such information might suggest a new direction in controlling treatment with safe elimination through dose adjustment and its associated alternatives in a judicious manner. A strategy to systematically focus on the safe elimination of anti-cancer drugs in RCC strongly needs advocating.

Effects of interleukin-2 in immunostimulation and immunosuppression

Distinctions in the nature and spatiotemporal expression of IL-2R subunits on conventional versus regulatory T cells are exploited to manipulate IL-2 immunomodulatory effects. Particularly, low-dose IL-2 and some recombinant derivatives are being evaluated to enhance/inhibit immune responses for therapeutic purposes.

Historically, interleukin-2 (IL-2) was first described as an immunostimulatory factor that supports the expansion of activated effector T cells. A layer of sophistication arose when regulatory CD4⁺ T lymphocytes (Tregs) were shown to require IL-2 for their development, homeostasis, and immunosuppressive functions. Fundamental distinctions in the nature and spatiotemporal expression patterns of IL-2 receptor subunits on naive/memory/effector T cells versus Tregs are now being exploited to manipulate the immunomodulatory effects of IL-2 for therapeutic purposes. Although high-dose IL-2 administration has yielded discrete clinical responses, low-dose IL-2 as well as innovative strategies based on IL-2 derivatives, including “muteins,” immunocomplexes, and immunocytokines, are being explored to therapeutically enhance or inhibit the immune response.

Antibody-cytokine fusion proteins: A novel class of biopharmaceuticals for the therapy of cancer and of chronic inflammation

Antibody-cytokine fusion proteins represent a novel class of biopharmaceuticals, with the potential to increase the therapeutic index of cytokine 'payloads' and to promote leukocyte infiltration at the site of disease. In this review, we present a survey of immunocytokines that have been used in preclinical models of cancer and in clinical trials. In particular, we highlight how antibody format, choice of target antigen and cytokine engineering, as well as combination strategies, may have a profound impact on therapeutic performance. Moreover, by using anti-inflammatory cytokines, antibody fusion strategies can conveniently be employed for the treatment of auto-immune and chronic inflammatory conditions.

Interferon-α versus interleukin-2 in Chinese patients with malignant melanoma: a randomized, controlled, trial

The US Food and Drug Association has approved interferon-α (IFN-α) and interleukin-2 (IL-2) as adjuvant therapy in malignant melanoma. The objective of the study was to compare efficacy and safety of subcutaneous interferon-α with continuous intravenous IL-2 in Chinese patients with malignant melanoma. A total of 250 patients with unresectable malignant melanoma were subjected to randomized in 1 : 1 ratio. Patients received subcutaneous 9×10 IU/m IFN-α (IFN-α group, n=125) or continuous intravenous 9×10 IU/m IL-2 (IL-2 group, n=125) at every 21 days for 4 months. The response, progression-free survival, overall survival, adverse effects, and cost were evaluated by experts in the field. IL-2 and IFN-α were effective in improvement of malignant melanoma after 4 months of intervention. IL-2 was effective in improving brain metastasis. Patients of the IL-2 group had a higher overall survival (P<0.0001) and a higher progression-free survival (P=0.002) than those of IFN-α group. The IL-2 group reported hypotension, kidney dysfunction, liver dysfunctions, flu-like symptoms, and capillary leak syndrome as adverse effects. IFN-α group reported thrombocytopenia and neutropenia as adverse effects. Healthcare management and expert charges lead to increase in the cost of treatment for IL-2 group patients than IFN-α group (P<0.0001). Continuous intravenous IL-2 should be recommended in relapse-free Chinese patients with malignant melanoma. Level of Evidence: I.

The challenges and molecular approaches surrounding interleukin-2-based therapeutics in cancer

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IL2-based cancer therapies are limited by their toxicity and pleiotropy.

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Current engineering approaches target IL2 half-life and cell/receptor specificity.

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IL2 may enhance the efficacy of checkpoint inhibitors and CAR-T-based therapies.

Interleukin-2 has had a long history as a promising cancer therapeutic, being capable of eliciting complete and durable remissions in patients with metastatic renal cell carcinoma and metastatic melanoma. Despite high toxicity and efficacy limited to only certain patient subpopulations and cancer types, the prospective use of novel, engineered IL2 formats in combination with the presently expanding repertoire of immuno-oncological targets remains very encouraging. This is possible due to the significant research efforts in the IL2 field that have yielded critical structural and biological insights that have made IL2 more effective and more broadly applicable in the clinic. In this review, we discuss some of the molecular approaches that have been used to further improve IL2 therapy for cancer.

Trial Watch: Immunostimulation with recombinant cytokines for cancer therapy

Cytokines regulate virtually aspects of innate and adaptive immunity, including the initiation, execution and extinction of tumor-targeting immune responses. Over the past three decades, the possibility of using recombinant cytokines as a means to elicit or boost clinically relevant anticancer immune responses has attracted considerable attention. However, only three cytokines have been approved so far by the US Food and Drug Administration and the European Medicines Agency for use in cancer patients, namely, recombinant interleukin (IL)-2 and two variants of recombinant interferon alpha 2 (IFN-α2a and IFN-α2b). Moreover, the use of these cytokines in the clinics is steadily decreasing, mostly as a consequence of: (1) the elevated pleiotropism of IL-2, IFN-α2a and IFN-α2b, resulting in multiple unwarranted effects; and (2) the development of highly effective immunostimulatory therapeutics, such as immune checkpoint blockers. Despite this and other obstacles, research in the field continues as alternative cytokines with restricted effects on specific cell populations are being evaluated. Here, we summarize research preclinical and clinical developments on the use of recombinant cytokines for immunostimulation in cancer patients.

Sequence of treatment in locally advanced and metastatic renal cell carcinoma

The spectrum of drugs that have shown activity in advanced or metastatic renal cell carcinoma (RCC) has led to a debate on the optimal sequence of treatments. There is agreement on recommending targeted agents as the standard of care in this disease. Uncertainty, however, remains on the best first-line drug choice. Physicians and patients may select sunitinib, bevacizumab in combination with interferon-alpha (IFN-α), pazopanib, or-in poor risk patients-temsirolimus. There are also a variety of therapies with proven efficacy on hand in the second-line setting: sorafenib, pazopanib, axitinib, and everolimus. While most randomized RCC trials assessed progression free survival (PFS) as primary endpoint, some agents were shown to improve median overall survival (OS), and given in sequence they have extended the life expectancy of RCC patients from 13 months in the cytokine era to over 30 months. Despite the progress made, there are sobering aspects to the oncologic success story in RCC, as the new treatments do not obtain an objective response or disease stabilization (SD) in all patients. There are also as yet no predictors to select patients who might benefit and those who are primary resistant to specific drugs, and ultimately almost all patients will experience disease progression. Bearing inevitable treatment failure in mind, availability of further drugs and switching therapy while the patient is in a condition to continue pharmacotherapy is essential. Of note, depending on the setting, only 33-59% of patients receive second-line treatment. In this review we present data on first-, second-, and third-line treatment in RCC, and discuss the difficulties in their interpretation in the context of treatment sequence. We summarize biological aspects and discuss mechanisms of resistance to anti-angiogenic therapy and their implications for treatment selection.

Cytokines

Cytokines, currently known to be more than 130 in number, are small MW (<30 kDa) key signaling proteins that modulate cellular activities in immunity, infection, inflammation, and malignancy. Key to understanding their function is recognition of their pleiotropism and often overlapping and functional redundancies. Classified here into 9 main families, most of the 23 approved cytokine preparations (19 different cytokines and 4 pegylated), all in recombinant human (rh) form, are grouped in the hematopoietic growth factor, interferon (IFN), platelet-derived growth factor (PDGF), and transforming growth factor β (TGFβ) families. In the hematopoietin family, approved cytokines are aldesleukin (rhIL-2), oprelvekin (rhIL-11), filgrastim and tbo-filgrastim (rhG-CSF), sargramostim (rhGM-CSF), metreleptin (rh-leptin), ancestim (rh-SCF), and the rh-erythropoietins, epoetin and darbepoetin alfa. Anakinra, a recombinant receptor antagonist for IL-1, is in the IL-1 family; recombinant interferons alfa-1, alfa-2, beta-1, and gamma-1 make up the interferon family; palifermin (rhKGF) and becaplermin (rhPDGF) are in the PDGF family; and rhBMP-2 and rhBMP-7 represent the TGFβ family. The main physicochemical features, FDA-approved indications, modes of action and side effects of these approved cytokines are presented. Underlying each adverse events profile is their pleiotropism, potency and capacity to release other cytokines producing cytokine “cocktails.” Side effects, some serious, occur despite cytokines being endogenous proteins, and this therefore demands caution in attempts to introduce individual members into the clinic. This caution is reflected in the relatively small number of cytokines currently approved by regulatory agencies and by the fact that 15 of the FDA-approved preparations carry warnings, with 10 being black box warnings.

Heme oxygenase-1 is a predictive biomarker for therapeutic targeting of advanced clear cell renal cell carcinoma treated with sorafenib or sunitinib

Background

We analyzed the expression of heme oxygenase-1 (HO-1) in patients undergoing radical nephrectomy for advanced clear cell renal cell carcinoma (CC-RCC) and evaluated the effects of the targeted therapies treated with sorafenib and sunitinib.

Methods

Expression of HO-1 in cancer tissue from 66 patients was measured by immunohis-tochemical staining. The patients received either oral sorafenib (n=40) or oral sunitinib (n=26) within 4 weeks after nephrectomy and were followed up long term to determine the tumor response and prognosis.

Results

Our current study revealed a high HO-1 expression level in 57.6% (38/66) of patients and a low HO-1 expression level in 42.4% (28/66) of patients with CC-RCC. The study also revealed that patients with high HO-1 expression did not have a higher objective response rate (2.6% versus 53.6%, P<0.01), clinical benefit rate (47.4% versus 92.9%, P<0.01), longer progression-free survival (4.4 versus 42 months, P=0.022), or overall survival (χ²=4.775, P=0.029) than patients with low HO-1 expression. In the low HO-1 level group, a higher tumor response rate and a longer survival time was achieved in patients who received sorafenib or sunitinib. Multivariate analysis showed that HO-1 expression was an independent prognostic factor for tumor response and overall survival.

Conclusion

High expression of HO-1 was associated with a lower tumor response rate and a shorter overall survival time when compared with low expression of HO-1. Overall, HO-1 expression might be a useful biomarker for predicting the response to sunitinib and sorafenib for patients with metastatic CC-RCC.

The optimal choice of medication administration route regarding intravenous, intramuscular, and subcutaneous injection

BACKGROUND

Intravenous (IV), intramuscular (IM), and subcutaneous (SC) are the three most frequently used injection routes in medication administration. Comparative studies of SC versus IV, IM versus IV, or IM versus SC have been sporadically conducted, and some new findings are completely different from the dosage recommendation as described in prescribing information. However, clinicians may still be ignorant of such new evidence-based findings when choosing treatment methods.

METHODS

A literature search was performed using PubMed, MEDLINE, and Web of Sciences™ Core Collection to analyze the advantages and disadvantages of SC, IV, and IM administration in head-to-head comparative studies.

RESULTS

"SC better than IV" involves trastuzumab, rituximab, antitumor necrosis factor medications, bortezomib, amifostine, recombinant human granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, recombinant interleukin-2, immunoglobulin, epoetin alfa, heparin, and opioids. "IV better than SC" involves ketamine, vitamin K1, and abatacept. With respect to insulin and ketamine, whether IV has advantages over SC is determined by specific clinical circumstances. "IM better than IV" involves epinephrine, hepatitis B immu-noglobulin, pegaspargase, and some antibiotics. "IV better than IM" involves ketamine, morphine, and antivenom. "IM better than SC" involves epinephrine. "SC better than IM" involves interferon-beta-1a, methotrexate, human chorionic gonadotropin, hepatitis B immunoglobulin, hydrocortisone, and morphine. Safety, efficacy, patient preference, and pharmacoeconomics are four principles governing the choice of injection route. Safety and efficacy must be the preferred principles to be considered (eg, epinephrine should be given intramuscularly during an episode of systemic anaphylaxis). If the safety and efficacy of two injection routes are equivalent, clinicians should consider more about patient preference and pharmacoeconomics because patient preference will ensure optimal treatment adherence and ultimately improve patient experience or satisfaction, while pharmacoeconomic concern will help alleviate nurse shortages and reduce overall health care costs. Besides the principles, the following detailed factors might affect the decision: patient characteristics-related factors (body mass index, age, sex, medical status [eg, renal impairment, comorbidities], personal attitudes toward safety and convenience, past experience, perception of current disease status, health literacy, and socioeconomic status), medication administration-related factors (anatomical site of injection, dose, frequency, formulation characteristics, administration time, indication, flexibility in the route of administration), and health care staff/institution-related factors (knowledge, human resources).

CONCLUSION

This updated review of findings of comparative studies of different injection routes will enrich the knowledge of safe, efficacious, economic, and patient preference-oriented medication administration as well as catching research opportunities in clinical nursing practice.

Side effects of cytokines approved for therapy

Cytokines, currently known to be more than 130 in number, are small MW (<30 kDa) key signaling proteins that modulate cellular activities in immunity, infection, inflammation and malignancy. Key to understanding their function is recognition of their pleiotropism and often overlapping and functional redundancies. Classified here into 9 main families, most of the 20 approved cytokine preparations (18 different cytokines; 3 pegylated), all in recombinant human (rh) form, are grouped in the hematopoietic growth factor, interferon, platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ) families. In the hematopoietin family, approved cytokines are aldesleukin (rhIL-2), oprelvekin (rhIL-11), filgrastim and tbo-filgrastim (rhG-CSF), sargramostim (rhGM-CSF), metreleptin (rh-leptin) and the rh-erythropoietins, epoetin and darbepoietin alfa. Anakinra, a recombinant receptor antagonist for IL-1, is in the IL-1 family; recombinant interferons alfa-1, alfa-2, beta-1 and gamma-1 make up the interferon family; palifermin (rhKGF) and becaplermin (rhPDGF) are in the PDGF family; and rhBMP-2 and rhBMP-7 represent the TGFβ family. The main physicochemical features, FDA-approved indications, modes of action and side effects of these approved cytokines are presented. Underlying each adverse events profile is their pleiotropism, potency and capacity to release other cytokines producing cytokine 'cocktails'. Side effects, some serious, occur despite cytokines being endogenous proteins, and this therefore demands caution in attempts to introduce individual members into the clinic. This caution is reflected in the relatively small number of cytokines currently approved by regulatory agencies and by the fact that 14 of the FDA-approved preparations carry warnings, with 10 being black box warnings.

Dendritic cell-based vaccination for renal cell carcinoma: challenges in clinical trials

After decades of research, dendritic cell (DC)-based vaccines for renal cell carcinoma have progressed from preclinical rodent models and safety assessments to Phase I/II clinical trials. DC vaccines represent a promising therapy that has produced measurable immunological responses and prolonged survival rates. However, there is still much room to improve in terms of therapeutic efficacy. The key issues that affect the efficiency and reliability of DC therapy include the selection of patients who will respond best to treatment, the proper preparation and administration of DC vaccines, and a combination of DC vaccination with other immune-enhancing therapies (e.g., removal of Tregs, CTLA-4 blockade and lymphodepletion). Additional antiangiogenic agents will hopefully lead to greater survival benefits for patients in early disease stages. This review focuses on the different approaches of DC-based vaccination against renal cell carcinoma and potential strategies to enhance the efficacy of DC vaccination.

An evaluation of a preparation of Mycobacterium vaccae (SRL172) as an immunotherapeutic agent in renal cancer

Two studies were carried out to evaluate heat-killed Mycobacterium vaccae SRL172 as an immunotherapeutic agent for patients with metastatic, post-nephrectomy, renal cell carcinoma. In the first study, 60 patients in France and the UK received injections of SRL172, and their survival was compared with that of historical controls who had been treated either with biological response modifiers (IL-2, IFN-alpha) or chemotherapy. In the second study, 36 patients were randomised to receive treatment with IL-2 alone or IL-2 plus SRL172. Survival and adverse events related to the treatments were assessed and compared between treatment groups. The first study showed that those treated with SRL172 alone survived equally as long as those receiving IL-2 or IFN-alpha and both treatment groups survived longer than those on chemotherapy (p<0.001), a result supported by Cox's proportional hazards regression analysis. The second study, stopped early due to drug supply issues, showed that the addition of SRL172 to IL-2 made no difference to survival compared to IL-2 alone, in the limited numbers treated. Adverse events occurring in those receiving SRL172 in the first study were mild and in the second study those receiving IL-2 alone had significantly more adverse events than those receiving SRL172 plus IL-2 (p<0.001). It is concluded that SRL172 may have activity in metastatic renal cancer and has very low toxicity, making it worthy of further study.

A randomized phase II trial of interleukin-2 in combination with four different doses of bryostatin-1 in patients with renal cell carcinoma

PURPOSE

Bryostatin-1 is a PKC modulator with direct anti-tumor activity and immunomodulatory properties. We combined different doses of Bryostatin-1 with IL-2 to determine effects on clinical response rate and T cell phenotype in patients with advanced kidney cancer.

EXPERIMENTAL DESIGN

IL-2 naïve patients were given 11 x 10(6) IU subcutaneously of IL-2 on days 1-4, 8-11, and 15-18 of every 28-day cycle. Twenty four patients were randomized to treatment cohorts of 5, 15 or 25 mcg/m2 of Bryostatin-1 on days 1, 8 and 15, starting in the second cycle. An additional nine, non-randomized patients were given 35 mcg/m2. Lymphocytes were analyzed for number, activation status, and production of IL-2, IL-4 and IFN-gamma. Response evaluation was performed every 3 cycles.

RESULTS

Common grade 3 toxicities included fatigue (5), nausea/vomiting (5), myopathy (3), dyspnea (3), and syncope (3). Four patients, in the two highest dose cohorts, demonstrated evidence of tumor shrinkage, although there was only 1 objective PR. The median time to progression was 104 days (95% CI 88-120) and the median survival was 452 days (95% CI = 424-480). There was no significant boosting effect of Bryostatin-1 on lymphocytes.

CONCLUSIONS

The addition of Bryostatin-1 to IL-2 was well tolerated, but the overall response rate was low (3.2%), indicating that further studies with this combination are not warranted.

Interleukin 21 therapy increases the density of tumor infiltrating CD8+ T cells and inhibits the growth of syngeneic tumors

Interleukin (IL)-21 is a recently discovered cytokine in early clinical development, which has shown anti-tumor activity in various animal models. In the present study, we examine the anti-tumor activity of IL-21 protein therapy in two syngeneic tumor models and its effect on the density of tumor infiltrating T cells. We treated mice bearing established subcutaneous B16 melanomas or RenCa renal cell carcinomas with intraperitoneal (i.p.) or subcutaneous (s.c.) IL-21 protein therapy and subsequently scored the densities of tumor infiltrating CD4(+) and CD8(+) T cells by immunohistochemistry. Whereas both routes of IL-21 administration significantly inhibited growth of small, established RenCa and B16 tumors, only s.c. therapy significantly inhibited the growth of large, established tumors. We found a greater bioavailability and significant drainage of IL-21 to regional lymph nodes following s.c. administration, which could account for the apparent increase in anti-tumor activity. Specific depletion of CD8(+) T cells with monoclonal antibodies completely abrogated the anti-tumor activity, whereas NK1.1(+) cell depletion did not affect tumor growth. In accordance, both routes of IL-21 administration significantly increased the density of tumor infiltrating CD8(+) T cells in both B16 and RenCa tumors; and in the RenCa model s.c. administration of IL-21 led to a significantly higher density of tumor infiltrating CD8(+) T cells compared to i.p. administration. The densities of CD4(+) T cells were unchanged following IL-21 treatments. Taken together, these data demonstrate that IL-21 protein has anti-tumor activity in established syngeneic tumors, and we show that IL-21 therapy markedly increases the density of tumor infiltrating CD8(+) T cells.

Immuntherapie des metastasierten Nierenzellkarzinoms mit Interleukin-2, Interferon-α2a und Erythropoetin-β

BACKGROUND

The combination of interferon-alpha2a (IFN-alpha2a) and interleukin-2 (IL-2) induces objective responses in patients with metastatic renal cell carcinoma (MRCC). Anaemia is associated with poor cancer control and reduced quality of life. The aim of the study was to investigate response rate and quality of life in patients with MRCC receiving the combination of Erythropoetin, IFN-alpha2a and IL-2.

MATERIAL AND METHOD

Patients with MRCC received epoetin beta (150 IU/kg and haemoglobin <130 g/l or 75 IU/kg and haemoglobin >or=130 g/l) three times weekly, from 14 days before and continuing throughout immunotherapy. In weeks 3-6 the patients received IFN-alpha2a 6 x 10(6) IU/m2 and IL-2 4.5 x 10(6) IU/m2 three times weekly on days 1, 3 and 5. The treatment was repeated two times and in the case of success a third cycle was added. The quality of life was assessed with the FACT questionnaire for fatigue, before, during and after therapy.

RESULTS

A total of 21 patients were treated, 19 of whom could be evaluated concerning response, toxicity and quality of life. We observed 1 complete remission, 2 partial remissions, 5 cases of stable disease and 11 with progressive disease. The overall response rate was 16%. Toxicity was mild to moderate; there were no WHO grade III or IV toxicity. The quality of life increased in ten patients, nine of whom exhibited an increase in their haemoglobin during therapy. Five of the nine patients with decreased quality of life also experienced a decrease in their haemoglobin. The correlation of increased haemoglobin and quality of life was significant (p<0.05).

CONCLUSION

The combination of IFN-alpha2a, IL-2 and epoetin beta resulted in objective remissions with mild to moderate toxicity. The quality of life correlates significantly with increasing haemoglobin.

Activity of Continuous Infusion Plus Pulse Interleukin-2 with Famotidine in Patients with Metastatic Kidney Cancer or Melanoma Previously Treated with Interleukin-2

Lymphokine-activated killer (LAK) cells generated by high-dose continuous infusion interleukin-2 (IL-2) are able to nonspecifically lyse melanoma and kidney cancer cells. In vitro famotidine enhances cytotoxicity of LAK against tumor cells, possibly by increasing IL-2 uptake at the IL-2 receptor on lymphocytes. Outpatient IL-2 regimens typically have response rates of 15% or less, with most patients eventually experiencing progressive disease. Second-line therapy is, therefore, needed. We treated 11 patients (6 with metastatic melanoma; 5 having metastatic kidney cancer) who had previously experienced progressive disease on prior IL-2 regimens, with a combination of famotidine 20 mg intravenously (i.v.) twice per day and continuous-infusion IL-2 18 MIU/M2/24 hours x 72 hours, followed 24 hours later by a pulse IL-2 dose (18 MIU/M2 over 15 minutes). Cycles were repeated every 3 weeks. Patient characteristics were: 9 males, median age 63 years (range, 57-75), median Eastern Cooperative Oncology Group (ECOG) performance status: 1; most common metastatic sites: lungs, lymph nodes, and soft tissue/subcutaneous (s.c.); median number of cycles received: 4; most common toxicities were fever, nausea/emesis, hypophosphatemia, and hypomagnesemia. Five (5) patients (3 with melanoma, 2 with kidney cancer) have had partial responses. Two (2) patients with kidney cancer have been converted to complete responders with resection of residual disease, remaining without relapse at 5+ and 20+ months. Responding sites are lungs, lymph nodes, abdominal mass, and s.c. Median duration of response was 9.5 months. Median survival was 12 months. This combination has activity in patients with metastatic kidney cancer or melanoma who have received prior IL-2.

Adjuvant subcutaneous interleukin-2 in patients with resected renal cell carcinoma: a pilot study

BACKGROUND

A pilot study was conducted to investigate the toxicity and tolerance to low-dose subcutaneous interleukin-2 (IL-2) for patients with resected renal cell carcinoma (RCC) at high risk for recurrent disease (TNM stages III and IV resected distant metastases).

PATIENTS AND METHODS

Patients with surgically resected locally advanced (T3-4 or N1-2) or metastatic RCC were randomly assigned to 1 of 4 treatment groups that received different dose levels and schedules of subcutaneous IL-2 as follows: dose level 1, 4 MIU/m2 per day, every other week for 24 weeks (n = 10); dose level 2, 8 MIU/m2 per day, every other week for 24 weeks (n = 9); dose level 3, 4 MIU/m2 per day, weeks 1-4, 9-12, and 17-20 (n = 11); and dose level 4, 8 MIU/m2 per day, weeks 1-4, 9-12, and 17-20 (n = 10). Interleukin-2 was administered in 2 daily doses on days 1-5 of each week indicated. A dose level was considered tolerable if no more than 2 patients experienced grade 3/4 toxicity.

RESULTS

Forty-one patients were entered in the study and 40 were evaluable for toxicity. Therapy was well tolerated at all dose levels and schedules, with most patients (98%) experiencing mild-to-moderate constitutional symptoms. Grade 3/4 toxicity was seen in 8 patients (20%). Interleukin-2 dose reductions were required in 7 patients, and no patient discontinued therapy secondary to toxicity. Of 39 patients evaluable for efficacy, 31 have experienced relapse (79%), and 15 have died (38%). Median survival was 1.4 years, and the 3-year disease-free survival rate was 33%. Median overall survival has not been reached; however, the 3-year survival rate was 70%. There was no statistically significant difference between any of the treatment arms with respect to disease-free survival or 3-year survival (P > 0.54 and P >or= 0.09 for all pairwise comparisons), schedules (dose level 1/2 vs. 3/4; P = 0.46 and P = 0.5), or dose of IL-2 administered (dose level 1/3 vs. 2/4; P = 0.99 and P = 0.1).

CONCLUSION

Subcutaneous IL-2 was well tolerated for 6 months in patients with surgically resected RCC at high risk of recurrence. Future adjuvant trials in this setting are not likely to include IL-2 in view of the clinical efficacy and favorable toxicity profiles of selected multitargeted kinase inhibitors.

Therapeutic Dendritic Cell Vaccination of Patients with Renal Cell Carcinoma

OBJECTIVE

Dendritic cell (DC) vaccination against cancer is a new specific immunotherapeutic approach given with either therapeutic or adjuvant intent. We provide a review of DC vaccination as a treatment for metastatic renal cell carcinoma (RCC).

METHOD

A total of 197 patients with metastatic RCC were treated with DC vaccination in 14 phase I/II clinical trials. Different vaccine preparations, administration routes, and treatment schedules have been tested in these trials. Clinical response and immune response were analysed.

RESULTS

Seventy-three (37%) patients had clinical response with 4 complete responses, 8 partial responses and 61 disease stabilisations, whereas 4 patients had mixed response, but most of these responses have not been transformed into durable clinical effects. Immune responses were observed in a subset of the treated patients but were not always associated with a clinical response. Only mild toxicity was observed in these trials.

CONCLUSION

DC vaccination therapy in patients with metastatic RCC is currently experimental but the results are encouraging with achievement of tumour regression and induction of antigen-specific immune response combined with minimal toxicity in a subset of the treated patients. Future emphasis should be placed on therapy in the adjuvant setting because patients with minimal residual disease are more likely to benefit from the treatment. Combination approaches with DC vaccination and immune-enhancing therapies or antiangiogenic therapy should be further investigated to develop new and more efficient treatment strategies for patients with RCC.

Novel treatments for metastatic renal cell carcinoma

The mainstay of any curative treatment in renal cell carcinoma (RCC) is surgery. In case of metastatic disease at presentation a radical nephrectomy is recommended to good performance status patients prior to start of interferon-alfa treatment. Interferon-alpha (IFN-alpha) offers in a small but significant percentage of patients advantage in overall survival; interleukin-2 (IL-2) based therapy gives similar survival rates. To date hormonal and chemotherapy do not have a proven impact on survival. The recent new insights in the molecular biology of clear RCC has revealed a key-role for vascular endothelial growth factor (VEGF) in the stimulation of angiogenesis in this highly vascularized tumour. This opens interesting new treatment strategies including: blockage of VEGF with the monoclonal antibody bevacizumab and inhibition of VEGF receptor tyrosine kinases (with small oral molecules such as SU11248 or PTK787). Likewise, inhibition of the Raf kinase pathway (with oral Bay 43-9006) or inhibition of the mTOR pathway (with i.v. CCI-779) are under investigation. Preliminary clinical results with all these compounds are interesting and the results of ongoing phase III studies will become available in the next years.

Surgical excision of isolated renal-bed recurrence after radical nephrectomy for renal cell carcinoma

OBJECTIVE

To present our results on managing loco-regional recurrence of renal cell carcinoma (RCC) with surgical excision, as local recurrence at the site of a previous nephrectomy is resistant to both systemic therapy and radiotherapy.

PATIENTS AND METHODS

In all, 16 patients were operated on between 1994 and 2003 for local recurrence of RCC. The median (mean, range) age at the time of local recurrence was 57.9 (57.4, 28.9-71.7) years, and the median interval from primary surgery 2.22 (3.88, 0.27-14.46) years. Before surgery eight patients had been given systemic immunotherapy, with no response of their local recurrence.

RESULTS

Two patients were deemed inoperable because of direct invasion of the great vessels and the liver by tumour. The remaining 14 patients had recurrence in residual adrenal tissue (two), para-aortic nodes (three), para-caval nodes (two), retrocaval nodes (one), renal bed (six), liver, spleen and stomach (one each), and diaphragm (two). Although complete macroscopic en-bloc clearance was achieved in these patients, only eight had tumour-free margins on histological examination. The histology was consistent with RCC recurrence in all cases. All of the patients were followed with computed tomography at regular intervals. At a median follow-up of 1.0 (1.65, 0.25-6.5) years, five patients remain disease-free, four have local and distant relapse, and five developed distant metastasis only. The presence of tumour at the resection margin was a significant factor in predicting local and distant disease-free survival (P < 0.05).

CONCLUSIONS

En bloc excision of isolated locally recurrent RCC is possible, and complete surgical extirpation can lead to prolonged disease-free survival.