Robert M. Conry

gp100 Peptide Vaccine and Interleukin-2 in Patients with Advanced Melanoma

BACKGROUND Stimulating an immune response against cancer with the use of vaccines remains a challenge. We hypothesized that combining a melanoma vaccine with interleukin-2, an immune activating agent, could improve outcomes. In a previous phase 2 study, patients with metastatic melanoma receiving high-dose interleukin-2 plus the gp100:209-217(210M) peptide vaccine had a higher rate of response than the rate that is expected among patients who are treated with interleukin-2 alone. METHODS We conducted a randomized, phase 3 trial involving 185 patients at 21 centers. Eligibility criteria included stage IV or locally advanced stage III cutaneous melanoma, expression of HLA*A0201, an absence of brain metastases, and suitability for high-dose interleukin-2 therapy. Patients were randomly assigned to receive interleukin-2 alone (720,000 IU per kilogram of body weight per dose) or gp100:209-217(210M) plus incomplete Freunds adjuvant (Montanide ISA-51) once per cycle, followed by interleukin-2. The primary end point was clinical response. Secondary end points included toxic effects and progression-free survival. RESULTS The treatment groups were well balanced with respect to baseline characteristics and received a similar amount of interleukin-2 per cycle. The toxic effects were consistent with those expected with interleukin-2 therapy. The vaccine-interleukin-2 group, as compared with the interleukin-2-only group, had a significant improvement in centrally verified overall clinical response (16% vs. 6%, P=0.03), as well as longer progression-free survival (2.2 months; 95% confidence interval [CI], 1.7 to 3.9 vs. 1.6 months; 95% CI, 1.5 to 1.8; P=0.008). The median overall survival was also longer in the vaccine-interleukin-2 group than in the interleukin-2-only group (17.8 months; 95% CI, 11.9 to 25.8 vs. 11.1 months; 95% CI, 8.7 to 16.3; P=0.06). CONCLUSIONS In patients with advanced melanoma, the response rate was higher and progression-free survival longer with vaccine and interleukin-2 than with interleukin-2 alone. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00019682.).

Bcl-2 Antisense (oblimersen sodium) Plus Dacarbazine in Patients With Advanced Melanoma: The Oblimersen Melanoma Study Group

PURPOSE Chemotherapy resistance in melanoma has been linked to antiapoptotic effects mediated by Bcl-2 protein. We evaluated whether targeting Bcl-2 using an antisense oligonucleotide (oblimersen sodium) could improve the efficacy of systemic chemotherapy in patients with advanced melanoma. PATIENTS AND METHODS We randomly assigned chemotherapy-naïve patients with advanced melanoma to treatment with dacarbazine (1,000 mg/m2) alone or preceded by a 5-day continuous intravenous infusion of oblimersen sodium (7 mg/kg/d) every 3 weeks for up to eight cycles. Patients were stratified by Eastern Cooperative Oncology Group performance status, liver metastases, disease site, and serum lactate dehydrogenase (LDH). The primary efficacy end point was overall survival. RESULTS Among 771 patients randomly assigned, the addition of oblimersen to dacarbazine yielded a trend toward improved survival at 24-month minimum follow-up (median, 9.0 v 7.8 months; P = .077) and significant increases in progression-free survival (median, 2.6 v 1.6 months; P < .001), overall response (13.5% v 7.5%; P = .007), complete response (2.8% v 0.8%), and durable response (7.3% v 3.6%; P = .03). A significant interaction between baseline serum LDH and treatment was observed; oblimersen significantly increased survival in patients whose baseline serum LDH was not elevated (median overall survival, 11.4 v 9.7 months; P = .02). Neutropenia and thrombocytopenia were increased in the oblimersen-dacarbazine group; however, there was no increase in serious infections or bleeding events. CONCLUSION The addition of oblimersen to dacarbazine significantly improved multiple clinical outcomes in patients with advanced melanoma and increased overall survival in patients without an elevated baseline serum LDH.

Human immune response to monoclonal antibodies.

Monoclonal antibodies either of mouse, mouse/human chimeric, or human origin have been used safely in human trials for a decade. Considerable effort has been committed in investigations of manipulating endogenous immunological activity against tumors and targeting various cytotoxic agents to cancers. These studies have identified several problems that need to be resolved before any such reagents can be used routinely in patients. One of these problems has been the immunogenicity of these monoclonal antibodies. This review article discusses what is known regarding human immune response to monoclonal antibodies and their clinical consequences.

Extended schedule, escalated dose temozolomide versus dacarbazine in stage IV melanoma: final results of a randomised phase III study (EORTC 18032)

PURPOSE To compare the efficacy of an extended schedule escalated dose of temozolomide versus standard dose dacarbazine in a large population of patients with stage IV melanoma. PATIENTS AND METHODS A total of 859 patients were randomised to receive oral temozolomide at 150 mg/m(2)/day for seven consecutive days every 2 weeks or dacarbazine, administered as an intravenous infusion at 1000 mg/m(2)/day on day 1 every 3 weeks. The primary endpoint was overall survival (OS), using an intent-to-treat principle. EudraCT number 2004-000654-23 NCI registration number NCT00005052. RESULTS Median OS was 9.1 months in the temozolomide arm and 9.4 months in the dacarbazine arm, with a hazard ratio (HR) of 1.00 (95%confidence interval [CI]: 0.86, 1.17; P=0.99). Median progression-free survival (PFS) was 2.3 months in the temozolomide arm and 2.2 months in the dacarbazine arm, with a HR of 0.92 (95%CI: 0.80, 1.06; P=0.27). In patients with measurable disease, overall response rate was higher in the temozolomide arm than in the dacarbazine arm (14.5% versus 9.8%, respectively), but the median duration of response was longer for dacarbazine. The extended schedule, escalated dose temozolomide arm showed more toxicity than the standard dose, single agent dacarbazine arm. The most common non-haematological treatment emergent adverse events reported in both treatment arms were nausea, fatigue and vomiting and constipation. CONCLUSION Extended schedule escalated dose Temozolomide (7 days on 7 days off) is feasible and has an acceptable safety profile, but does not improve OS and PFS in metastatic melanoma when compared to standard dose dacarbazine.

A phase III multi-institutional randomized study of immunization with the gp100: 209–217(210M) peptide followed by high-dose IL-2 compared with high-dose IL-2 alone in patients with metastatic melanoma

CRA9011 Background: In a phase II study, 13 (42%) of 31 patients with metastatic melanoma receiving high-dose (HD) IL-2 plus gp100:209-217(210M) peptide experienced objective responses (S.A. Rosenberg, et al, Nature Medicine 4: 321-327, 1998). Other studies showed a lower response rate (RR) but no randomized studies have been done. METHODS A prospective randomized phase III trial was conducted at 21 centers with 185 patients. Eligibility: stage IV or locally advanced stage III cutaneous melanoma, HLA A0201, no brain metastases, eligible for HD IL-2, and no previous HD IL-2 or gp100:209-217(210M). Arm 1 received HD IL-2 alone (720,000 IU/kg/dose) and Arm 2 gp100:209-217(210M) peptide + Montanide ISA followed by HD IL-2. The primary objective was clinical response. Secondary objectives were toxicity, disease free/progression free survival, immunologic response and quality of life. Central HLA typing, pathology review, and blinded response assessment were done at the NIH. Central data monitoring was done by The EMMES Corp. and a Data Safety Monitoring Board. RESULTS Numbers of patients enrolled, treated, and evaluable for response in Arm 1 were 94, 93, and 93 respectively; in Arm 2 91, 86, and 86. Toxicities were consistent with HD IL-2 ± vaccine. Investigator assessed RR showed significant improvement in overall RR for Arm 2=22.1% vs 9.7% (P=0.0223, Chi-Square) and progression free survival (PFS) in favor of Arm 2=2.9 months (1.7-4.5) vs 1.6 (1.5-1.8) (P=0.0101). Median overall survival favors Arm 2=17.6 months (11.8-26.6) vs 12.8 (8.7-16.3) (P=0.0964). Blinded response review is ongoing. CONCLUSIONS RR and PFS were superior with peptide vaccine and HD IL-2 compared to HD IL-2 alone. This represents the first evidence of clinical benefit of vaccination in patients with melanoma. [Table: see text].

Combination Chemotherapy and ALVAC-CEA/B7.1 Vaccine in Patients with Metastatic Colorectal Cancer

Purpose: The combination of vaccines and chemotherapy holds promise for cancer therapy, but the effect of cytotoxic chemotherapy on vaccine-induced antitumor immunity is unknown. This study was conducted to assess the effects of systemic chemotherapy on ALVAC-CEA/B7.1–induced T-cell immunity in patients with metastatic colorectal cancer. Experimental Design: Patients with metastatic colorectal cancer were treated with fluorouracil, leucovorin, and irinotecan and were also given ALVAC-CEA/B7.1 vaccine with or without tetanus toxoid adjuvant. Eligible patients were randomized to ALVAC followed by chemotherapy and booster vaccination (group 1), ALVAC and tetanus toxoid followed by chemotherapy (group 2), or chemotherapy alone followed by ALVAC in patients without disease progression (group 3). Humoral immune responses were measured by standard ELISA assay, and carcinoembryonic antigen (CEA)-specific T-cell responses were measured by IFN-γ enzyme-linked immunospot assay. Results: One hundred eighteen patients were randomized to receive either ALVAC before and concomitantly with chemotherapy (n = 39), ALVAC with tetanus adjuvant before and concomitantly with chemotherapy (n = 40), or chemotherapy followed by ALVAC (n = 39). Serious adverse events were largely gastrointestinal (n = 30) and hematologic (n = 24). Overall, 42 patients (40.4%) showed objective clinical responses. All patients developed antibody responses against ALVAC, but increased anti-CEA antibody titers were detected in only three patients. Increases in CEA-specific T cells were detected in 50%, 37%, and 30% of patients in groups 1, 2, and 3, respectively. There were no differences in clinical or immune responses between the treatment groups. Conclusion: The combination of ALVAC-CEA/B7.1 vaccine and systemic chemotherapy has an acceptable safety profile in patients with metastatic colorectal cancer. Systemic chemotherapy did not affect the generation of CEA-specific T-cell responses following vaccination.

Phase 3 study of docosahexaenoic acid–paclitaxel versus dacarbazine in patients with metastatic malignant melanoma

BACKGROUND Docosahexaenoic acid-paclitaxel (DHA-paclitaxel, Taxoprexin(®)) is made by covalently conjugating the essential fatty acid DHA to the paclitaxel molecule. Preclinical studies of DHA-paclitaxel have demonstrated increased activity relative to paclitaxel and the potential for an improved therapeutic ratio. In the present study, the efficacy and toxicity profiles of DHA-paclitaxel were compared with those of dacarbazine. METHODS In this study, 393 chemonaive patients with metastatic melanoma were randomly assigned to receive either DHA-paclitaxel at a starting dose of 900 mg/m(2) IV on day 1 every 3 weeks or dacarbazine at a starting dose of 1000 mg/m(2) IV on day 1 every 3 weeks. The primary end point of the study was the comparison of overall survival (OS). RESULTS No significant difference in OS was noted between patients in the DHA-paclitaxel and dacarbazine arms. Similarly, there were no significant differences in response rate, duration of response, time to progression, and time to treatment failure between the two drugs. Safety results of the two drugs were as predicted from prior studies. Myelosuppression was more common with DHA-paclitaxel. CONCLUSIONS DHA-paclitaxel was not superior to dacarbazine. We conclude that further studies with the drug on an every 3-week schedule in melanoma are not warranted.

Incorporation of β-globin untranslated regions into a Sindbis virus vector for augmentation of heterologous mRNA expression

Polynucleotide immunization has been employed as a means of inducing immune responses through the introduction of antigen-encoding DNA. While immunization against specific tumor antigens may be achieved through this strategy, various candidate tumor antigens may not be approached via DNA-based vaccines as they represent transforming oncogenes. As an alternative approach, we have explored the utility of mRNA vectors for polynucleotide immunization. The transient expression achieved by mRNA may provide an efficient and safe system for stimulating immune responses to tumor-specific antigens. Our previous work demonstrated that a self-replicating RNA enhances the magnitude and duration of transgene expression for this application. Here we further modify the vector for optimal use in gene therapy through the incorporation of untranslated regions flanking the encoded transgene. The β-globin 5′ and 3′ untranslated regions (UTRs) were inserted directly flanking the luciferase gene in both nonreplicative and replicative RNA constructs. In both cases, elevated and prolonged levels of luciferase expression were detected from the β-globin UTR-flanked luciferase as compared to luciferase without these sequences. These modifications improve the ability of replicative RNA vectors to produce high, yet transient transgene expression for cancer immunotherapy strategies.

Phase I Study of the Intratumoral Administration of Recombinant Canarypox Viruses Expressing B7.1 and Interleukin 12 in Patients with Metastatic Melanoma

The objective of this study was to evaluate the safety and activity of the intratumoral administration of the immune costimulatory molecule, B7.1, encoded by a vector derived from the canarypox virus, ALVAC (ALVAC-B7.1), alone and with the intratumoral injection of ALVAC encoding the immune-stimulatory cytokine, interleukin 12 (ALVAC-IL-12). Fourteen patients with metastatic melanoma who had s.c. nodules received intratumoral injections on days 1, 4, 8, and 11. Nine patients were given escalating doses of up to 25 × 108 plaque-forming units of ALVAC-B7.1. Five patients were given 25 × 108 plaque-forming units of ALVAC-B7.1 combined with ALVAC-IL-12 50% tissue culture infective dose of 2 × 106. Toxicity was mild to moderate and consisted of inflammatory reactions at the injection site and fever, chills, myalgia, and fatigue. Higher levels of B7.1 mRNA were observed in ALVAC-B7.1–injected tumors compared with saline-injected control tumors. Higher levels of intratumoral vascular endothelial growth factor and IL-10, cytokines with immune suppressive activities, were also observed in ALVAC-B7.1– and ALVAC-IL-12–injected tumors compared with saline-injected controls. Serum levels of vascular endothelial growth factor increased at day 18 and returned to baseline at day 43. All patients developed antibody to ALVAC. Intratumoral IL-12 and IFN-γ mRNA decreased. Changes in serum IL-12 and IFN-γ levels were not observed. Tumor regressions were not observed. The intratumoral injections of ALVAC-B7.1 and ALVAC-IL-12 were well tolerated at these dose levels and at this schedule and resulted in measurable biological response. This response included the production of factors that may suppress the antitumor immunologic activity of these vectors.

Phase I trial of an anti-CD19 deglycosylated ricin A chain immunotoxin in non-Hodgkin's lymphoma : Effect of an intensive schedule of administration

In a phase I trial, eight patients with non-Hodgkins B-cell lym-phoma received mouse IgG1k monoclonal antibody HD37 specific for CD19 conjugated to deglycosylated ricin A chain (dgA) administered in four doses at 4-h intervals with total doses ranging from 4− 12 mg/m2. This schedule generated serum levels of immunotoxin which were sustained over 36 h. The plasma half-life of HD37-dgA was 17 ± 4 (SD) h. The HD37-dgA conjugate was stable in vivo as demonstrated by serum levels of HD37-dgA conjugate comparable to those of total HD37 antibody. Peak serum levels attained after the fourth dose ranged from 0.36 to 5.63 μg/ml. Two of seven evaluable patients developed modest human anti-immunotoxin antibody responses. Toxicity in patients 1–7 consisted of dose-dependent capillary leak syndrome with hypoalbuminemia, orthostatic hypotension, and weight gain. Patient 8 died on day 8 with severe capillary leak, bronchopneumonia, and rhabdomyolysis. All patients had progressive disease at 4 weeks except patient 8, who exhibited a near-complete remission before his death. This intensive schedule appears to produce inordinate toxicity with a maximal tolerated total dose of 8 mg/m2.