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Background Despite improved survival following checkpoint inhibitors, there is still a potential role for anti-cancer therapeutic vaccines. Because of biological heterogeneity and neoantigens resulting from each patient’s mutanome, autologous tumor may be the best source of tumor-associated antigens (TAA) for vaccines. Ex vivo loading of autologous dendritic cells with TAA may be associated with superior clinical outcome compared to injecting irradiated autologous tumor cells. We conducted a randomized phase II trial to compare autologous tumor cell vaccines (TCV) and autologous dendritic cell vaccines (DCV) loaded with autologous TAA. Methods Short-term autologous tumor cell lines were established from metastatic tumor. Vaccines were admixed with 500 micrograms of GM-CSF and injected weekly for 3 weeks, then at weeks 8, 12,16, 20, and 24. The primary endpoint was overall survival. Secondary objectives were identification of adverse events, and results of delayed type hypersensitivity (DTH) reactions to intradermal tumor cell injections. Results Forty-two patients were randomized. All were followed from randomization until death or for five years; none were lost to follow-up. DCV was associated with longer survival: median 43.4 versus 20.5 months (95% CI, 18.6 to > 60 versus 9.3 to 32.3 months) and a 70% reduction in the risk of death (hazard ratio = 0.304, p = 0.0053, 95% CI, 0.131 to 0.702). Tumor DTH reactions were neither prognostic nor predictive. The most common treatment-related adverse events were mild to moderate local injection site reactions and flu-like symptoms; but grade 2 treatment-related adverse events were more frequent with TCV. Serum marker analyses at week-0 and week-4 showed that serum markers were similar at baseline in each arm, but differed after vaccination. Conclusions This is the only human clinical trial comparing DCV and TCV as platforms for autologous TAA presentation. DCV was associated with minimal toxicity and long-term survival in patients with metastatic melanoma. DTH to autologous tumor cells was neither prognostic for survival nor predictive of benefit for either vaccine. Trial registration Clinical trials.gov NCT00948480 retrospectively registered 28 July 2009. Electronic supplementary material The online version of this article (10.1186/s40425-018-0330-1) contains supplementary material, which is available to authorized users.

Aim: Metastatic melanoma patients were treated with patient-specific vaccines consisting of autologous dendritic cells loaded with antigens from irradiated cells from short-term autologous tumor cell lines. Patients & methods: A total of 72 patients were enrolled in a single-arm Phase I/II (NCT00948480) trial or a randomized Phase II (NCT00436930). Results: Toxicity was minimal. Median overall survival (OS) was 49.4 months; 5-year OS 46%. A 5-year OS was 72% for 18 recurrent stage 3 without measurable disease when treated and 53% for 30 stage 4 without measurable disease when treated. A total of 24 patients with measurable stage 4 when treated (median of four prior therapies) had an 18.5 months median OS and 46% 2-year OS. Conclusion: This dendritic cell vaccine was associated with encouraging survival in all three clinical subsets. Clinicaltrial.gov NCT00436930 and NCT00948480.

In patients with metastatic melanoma, sequential single-arm and randomized phase II trials with a therapeutic vaccine consisting of autologous dendritic cells (DCs) loaded with antigens from self-renewing, proliferating, irradiated autologous tumor cells (DC-TC) showed superior survival compared with similar patients immunized with irradiated tumor cells (TC). We wished to determine whether this difference was evident in cohorts who at the time of treatment had (1) no evidence of disease (NED) or (2) had detectable disease. Eligibility criteria and treatment schedules were the same for all three trials. Pooled data confirmed that overall survival (OS) was longer in 72 patients treated with DC-TC compared with 71 patients treated with TC (median OS 60 versus 22 months; 5-year OS 51% versus 32%, p=0.004). Treatment with DC-TC was associated with longer OS in both cohorts. Among 70 patients who were NED at the time that treatment was started, OS was better for DC-TC: 5-year OS 73% versus 43% (p=0.015). Among 73 patients who had detectable metastases, OS was better for DC-TC: median 38.8 months versus 14.7 months, 5-year OS 33% versus 20% (p=0.025). This approach is promising as an adjunct to other therapies in patients who have had metastatic melanoma.

Various published data show that in patients with metastatic melanoma, high-dose interleukin-2 (IL2) is associated with 5-year survival rates of 15% from treatment initiation. We previously reported a median survival of 15.6 months, and a 20% 5-year survival rate for 150 patients who were treated with inpatient IL2 (Cancer Biother Radiopharm 2012;27:337). In the current study, we sought to determine whether treatment with active specific immunotherapy (ASI) with patient-specific tumor stem cell vaccines derived from autologous tumor cell (TC) lines contributed to the survival result. Existing databases revealed that 32/149 IL2-treated patients also received ASI, while 117 did not. ASI was given within 12 months of IL2 therapy in 19/32 patients. Patients who received IL2 plus ASI had better overall survival (p0.001) with longer median survival (39.5 vs. 12.0 months) and a higher 5-year survival rate (39% vs. 13%). Survival was better even after exclusion of 55 IL2-alone patients who died before 12 months of follow-up (p=0.12). In subset analyses, survival was longer for 25 patients who received ASI after IL2 than for 7 who received ASI before IL2 (5-year survival 46% vs. 14%, p0.001) and for 16 patients who received a dendritic cell/TC-based ASI compared with 16 injected with irradiated TC (p=0.17). This retrospective study suggests that receipt of IL2 followed by a patient-specific melanoma stem cell vaccine is associated with better survival than IL2 alone.

Only 10% of metastatic melanoma patients survive 5 years, even though many can achieve substantial tumor reduction by surgical resection and/or radiation therapy and/or systemic therapy. An effective, nontoxic, consolidation immunotherapy could benefit such patients. We initiated a randomized trial to compare 2 promising patient-specific immunotherapy cell products. Patients had to have a diagnosis of metastatic melanoma and availability of an autologous melanoma cell line. Patients were stratified by whether their most advanced stage had been regional or distant metastases, and by whether they had measurable disease at the time of treatment, then they were randomized to receive irradiated autologous proliferating tumor cells or autologous dendritic cells (DC) loaded with antigens from such cells. Both products were injected subcutaneously in 500 µg of granulocyte-macrophage colony stimulating factor, weekly for 3 weeks and then monthly for 5 months. Patients in the 2 arms did not differ in baseline characteristics. All patients received prescribed therapy. Treatment was well tolerated. At the time of initial analysis, with no patients lost to follow-up, 50% of patients deceased, and all surviving patients followed for at least 6 months after randomization, survival is superior in the DC arm (hazard ratio, 0.27; 95% confidence interval, 0.098-0.729) with median survival not reached versus 15.9 months, and 2-year survival rates of 72% versus 31% (P=0.007). This trial provides evidence that a DC vaccine is associated with longer survival compared with a tumor cell vaccine, and is consistent with previous data suggesting a survival benefit from this patient-specific immunotherapy.

Previously, a 54% 5-year survival was reported for metastatic melanoma patients treated with patient-specific vaccines consisting of autologous dendritic cells loaded with antigens from autologous proliferating tumor cells. This study attempted to determine which clinical and laboratory factors best explained long-term survival in this group of patients. Univariate analyses were used to identify factors associated with continuous survival after initiating vaccine therapy. Multivariate logistic regression was used to identify independent factors to classify survival at 3.5 years. Survivors were followed a minimum of 3.7 years (median: 5.7). Univariate analyses identified eight features associated with improved survival: Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0, no measurable disease at study entry, receiving 8 vaccinations, age50 years, normal baseline lactate dehydrogenase, no history of visceral metastases, anergy to standard skin tests, and failure of interferon-gamma (IFN-γ) to induce apoptosis in autologous tumor cells. After examining 54 variables for which complete information was available over all patients, the best multivariate regression for survival at 3.5 years utilized six features: prior radiation therapy, younger age, male gender, ECOG PS 0, higher numbers of cells administered during the first 3 injections, and lower numbers of viable cells administered during the first 3 injections. This model correctly classified survival for 28 of 32 patients (87%) and death for 20 of 22 (91%). When features with incomplete information were included in the analysis, addition of IFN-γ-induced apoptosis (n=49) improved predictive accuracy to 27 of 29 (93%) for survival and 19 of 20 (95%) for death. Dependencies between variables were common, but these multivariate linear models yielded high classification accuracy for survival at 3.5 years and identified two features of the vaccine itself as being of independent significance.

We conducted a multicenter, community-based phase II trial of PCR biochemotherapy (pentostatin 4 mg/m2, cyclophosphamide 600 mg/m2, and rituximab 375 mg/m2) every 3 weeks for up to 6 cycles in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). The study was stopped after enrolling 24 patients because of diminished investigator interest after 8 patients discontinued treatment because of adverse events, and 5 others died during treatment. The median age of patients was 69 years; 11 patients were over age 70, and 71% had Rai stage III or IV disease. The response rate among the 17 evaluable patients who completed 3 cycles of therapy was 58% (35%-81%, 95% confidence interval), with 2 complete responders (both greater than 70 years of age) and 7 partial responders. No patients developed progressive disease while receiving PCR. This is the first report of a trial in CLL utilizing a combination of purine analog, alkylator, and rituximab, in which most patients were older than 65 years and had high-risk disease. PCR is active in CLL/SLL, but appears to be less active and associated with more complications in the community setting, compared to trials with younger, lower risk patients who travel to academic referral centers for treatment.

Determination of potency is a challenging problem for patient-specific products derived from autologous cells. For several years, we have been investigating the safety and therapeutic potential of patient- specific vaccines derived from short-term autologous cell lines. We investigated whether clinical potency of these vaccines could be determined by retrospective correlation between the numbers of cells injected (quantity of tumor antigens) and clinical outcome.The averages and standard deviations of irradiated tumor cells were determined for those patients who received the first 3 weekly injections, and for the subset that had a recording of results from tumor delayed-type hypersensitivity testing (DTH). Correlations were made between the numbers of cells injected and DTH conversion and survival.One hundred fifty-six patients received the vaccine product, 136 of whom received the first 3 weekly vaccinations. The most common reason for not receiving 3 injections or having a repeat tumor DTH test was rapidly progressive disease. Ninety-nine patients had cell count data for all 3 injections; 73 had a tumor DTH test at baseline and at week 4. The average number of cells injected over 3 weeks, in millions per patient, by quartile were: 6.0 +/- 1.8, 10.2 +/- 1.4, 15.1 +/- 1.4, and 31.2 +/- 9.8, with respective median survivals of 24.7, 25.5, 24.0, and 21.0 months, with the respective number of DTH conversions being 4, 8, 4, and 6. There were no statistical differences in survival or in the number of patients who had a positive tumor DTH test at week 4.We were unable to define potency--based on a relationship between the number of tumor cells injected as part of vaccination and survival or the reactivity to pure autologous tumor--in a tumor DTH test, over the range of 2-30 million injected cells over 3 weeks.

The aim of this study was to investigate the feasibility, safety, and clinical efficacy of patient-specific dendritic cell vaccines in patients with metastatic melanoma. A planned interim analysis was conducted on the first 20 patients.Tumor cell lines were established from metastatic tumor, expanded to 200 million cells, and then incubated with interferon-gamma for patients who were candidates for therapy. Cells were irradiated and cryopreserved. Patients underwent leukapheresis to obtain mononuclear cells that were cultured in the presence of IL-4 and GM-CSF to produce dendritic cells, which were incubated with cryopreserved, irradiated tumor cells, and then stored in aliquots of about 20 million cells for subcutaneous (s.c.) injections with GM-CSF once a week for 3 weeks, then once a month for 5 months.The first 20 eligible patients included 10 men and 10 women, with a median age of 48 years (range, 16-79 years). Three (3) patients had brain metastases, and 13 patients had experienced disease progression after biochemotherapy. At the time of vaccine treatment, 6 patients had evaluable metastatic disease, while 14 patients lacked measurable disease. Vaccine therapy was well tolerated, except for what appeared to be GM-CSF-related allergic reactions in 2 patients. Delayed-type hypersensitivity (DTH) tests to irradiated tumor cells were positive in 0 of 20 patients tested at baseline, but converted to positive in 8 patients (40%). At a median follow-up of 13.8 months, there is a 95% overall survival and a 48% progression-free survival. Four (4) patients have already survived more than 3.0 years since starting the vaccine.Based on tolerability, rate of tumor DTH conversion, and encouraging survival, the trial will continue accrual to at least 19 patients with measurable disease and 40 patients who lack measurable disease at the time of treatment.

We previously reported the laboratory methodology for producing patient-specific irradiated autologous tumor-cell products derived from short-term cultured tumor cells from resected renal cell carcinoma, and described preliminary clinical results. In this study, we report the final clinical results and efforts to define vaccine potency on the basis of clinical outcome for these 25 patients with advanced renal cell carcinoma.Approximately 10(8) cells from successful short-term cell lines were irradiated, frozen in aliquots of 10(7) cells, then thawed and administered subcutaneously (s.c.) once a week for 3 weeks, then once a month for 5 months. Patients included 19 men and 6 women, who were 43-82 years of age. Six (6) patients had a large primary lesion, 2 patients had regionally advanced disease, 3 patients had been rendered disease-free by surgical resection of distant metastases, and 14 patients had measurable distant metastatic disease.The vaccines were well tolerated, and no delayed autoimmune effects were documented. Delayed-type hypersensitivity (DTH) tests of irradiated tumor cells were positive in only 1 of 25 patients at week 0, but converted to positive in 6 of 18 patients of DTH-negative patients who were retested at week 4. Objective response rate in patients who had measurable metastatic disease was 0 of 14 patients. With a median follow-up of greater than 7 years from the date of the first DTH test, median survival is 33.4 months, 5-year survival is 43%, and 10 patients are alive 3-12 years later. The 7 DTH+ patients survived a median of 2.5 years, and 3 patients are alive after 3, 4, and 7 years. There was no correlation between the number of irradiated cells or viable irradiated cells injected and tumor DTH reactivity or survival.This approach is feasible and the therapy is well tolerated, but clinical benefit was not established in this trial. Any further exploration of this product should be limited to the adjuvant setting in a randomized trial.

We previously reported the laboratory methodology for producing patient-specific irradiated autologous tumor-cell products derived from short-term cultured tumor cells. We attempted to determine the feasibility, safety, and clinical effects of autologous tumor vaccine-derived sarcomas.Efforts were made to establish tumor cell lines in tissue culture with expansion to 100 million cells for patients who were candidates for therapy. Cells were irradiated and cryopreserved in aliquots of 10 million cells for subcutaneous (s.c.) injections, once a week for 3 weeks, then once a month for 5 months.Efforts were made to establish short-term tumor cell lines from 86 fresh sarcoma specimens (10 primary, 14 recurrent, and 62 metastatic). Initial growth was successful for 48 patients (56%), and cultures were expanded for 36 patients, with 25 patients treated. There were 23 evaluable patients, including 12 women and 11 men, with a median age of 52 years and a range from 16-79 years. Vaccine therapy was well tolerated. Delayed-type hypersensitivity (DTH) tests to irradiated tumor cells were positive in 0 of 20 patients tested at baseline, but converted to positive after 3 weekly vaccinations in 8 of 16 patients who were retested. Median survival for the 8 DTH converters was 16.6 months versus 8.2 months for the 8 responders whose tumor DTH test remained negative, and 6.0 months for the 7 patients who were not tested. No objective responses were recorded among 12 evaluable patients with measurable disease; 10 patients have survived more than 1 year.This approach is feasible, well tolerated, and the resulting DTH conversion rate is of interest. Patients with minimal tumor burden would be preferred for further future testing.

The objective was to study the effects of patient-specific vaccine immunotherapy administered with either interferon-gamma (IFNgamma) or granulocyte-macrophage colony stimulating factor (GM-CSF) in patients with metastatic cancer. Short-term cell lines were established from cancer tissue resected from patients with metastatic cancer for use as autologous tumor cell vaccines. Successful cultures were expanded to 1 to 2 x 108 cells, irradiated, and cryopreserved in aliquots of 106 cells for intradermal testing of delayed tumor hypersensitivity and 107 cells for subcutaneous vaccinations. The study design was that of a randomized phase 2 trial. Patients were stratified by tumor type and by whether they had measurable disease at the time vaccination was to commence, and then randomized to receive either 100 MIU IFNgamma subcutaneously or 500 microg GM-CSF subcutaneously at the time of each tumor cell vaccination. Following a baseline test of delayed-type hypersensitivity (DTH) to an intradermal injection of 106 irradiated autologous tumor cells, patients received 3 weekly subcutaneous injections of 107 cells, had a repeat DTH test at week 4, then received monthly vaccinations for 5 months. A positive DTH test was defined as at least 10 mm of induration; survival was determined from the first DTH test. There were 98 patients enrolled with a median follow-up of over 4 years. The most prevalent diagnoses were melanoma (51), renal cell carcinoma (18), and soft-tissue sarcoma (14). There were 49 patients (26 men, 23 women, average age 50.4 years) randomized to IFNgamma and 49 (28 men, 21 women, average age 54.1 years) to GM-CSF. The average numbers of vaccine and adjuvant injections were 6.3 and 5.9, respectively. For the patients who received IFNgamma, the objective response rate was 0 of 21; for patients who received GM-CSF the response rate was 1 of 26. Only eight patients (four from each arm) had a positive baseline DTH reaction to autologous tumor. The tumor DTH test converted from negative to positive in 13 of 45 of the IFNgamma group and 11 of 43 of the GM-CSF group. With 29 patients deceased in the IFNgamma arm and 31 in the GM-CSF arm, the 2-year and 5-year survival rates were 45% and 29% for the IFNgamma arm and 41% and 23% for the GM-CSF arm (NSD). Both adjuvants were well tolerated and results were similar in both arms of the study. Both adjuvants were associated with a 25% to 30% rate of DTH conversion and a 25% 5-year survival rate. Immune recognition of autologous tumor can be induced with this approach.

The treatment of metastatic renal cell cancer remains unsatisfactory despite encouraging results with biotherapy. Pilot studies from other investigators have suggested that combining cis-retinoic acid and 5-fluorouracil (5FU) with interleukin-2 (IL-2) and interferon-alpha (IFN) may improve outcomes for such patients.Eligible patients had metastatic renal cell cancer, were in good medical condition, and had not been treated previously with more than two of the study agents. A 56-day treatment cycle consisted of: interferon-alpha 2a 3.0 mu/m2 s.c. Monday, Wednesday, and Friday weeks 1-8, interleukin-2 11 mu/m2 s.c. Tuesday, Thursday and Saturday of weeks 1-4, cis-retinoic acid 1 mg/kg p.o. daily weeks 1-8, and 5-FU 750 mg/m2 i.v. weekly during weeks 5-8. Patients were evaluated for tumor response every 8 weeks, and in the absence of tumor progression, patients could receive treatment for up to one year. Survival was determined from the first date of treatment.The 58 renal cell carcinoma patients included 41 men and 17 women, with a median age of 57 years with a range of 28-85 who were enrolled between October 1994 and July 1997. Thirty-seven percent were asymptomatic when treatment was initiated. Sites of disease at study entry included 62% lung, 34% bone, 31% lymph node, 22% kidney, 16% liver and 10% adrenal. There were only three patients with significant tumor responses (one complete, two partial) for a response rate of 5% (0-11% 95% CI) based on intent-to-treat analysis, and 6% (0-12%, 95% CI) for the 53 patients who were evaluable for response. The response rate among evaluable nephrectomized patients who had received no prior radiation or systemic treatment was 3/25 (12%). The median failure-free survival was 2.8 months; median overall survival was 10.9 months. The 1-year survival rate was 50% and 2-year survival rate was 33%. The most frequent toxicities were fatigue-81% (26% grade 3 or 4), nausea/vomiting-59%, and leukopenia/neutropenia 57% (16% grade 3 or 4).Despite a disappointing objective response rate, survival in these patients who were treated entirely as outpatients was similar to that seen in our earlier trials of inpatient, intermediate dose continuous infusion IL-2-based therapy.

We established short-term cultures of pure tumor cells for use as autologous tumor cell vaccines in an effort to study the effects of patients-specific immunotherapy.Surgically resected fresh tumor was obtained from patients with metastatic cancer. Successful tumor cell lines (5 x 10(7)) were expanded to 10(8) cells, irradiated, and cryopreserved for clinical use. Following a baseline test of delayed-type hypersensitivity (DTH) to an i.d. injection of 10(6) irradiated autologous tumor cells, patients received 3 weekly s.c. injections of 10(7) cells, had a repeat DTH test at week-4, then received monthly vaccinations for 5 months. A positive DTH test was defined asor = 10 mm induration; survival was determined from the first DTH test.Short-term cell lines were successfully established for 299/695 patients (43%). Vaccines were prepared for 231 patients, 142 of whom were treated, and 125 had a baseline DTH test recorded. Median follow up at the time of analysis was greater than 5 years. There was no difference in survival for any of the following: gender, age50 years, melanoma histology, anergy to common recall antigens or baseline DTH test result. Only 17 patients had a positive DTH at baseline (14%), but DTH converted from negative to positive in 31/80 (39%) of those who were tested, and in 31/108 (29%) of all patients (intent-to-convert analysis). For the 48 patients who were DTH-positive at entry, or converted to DTH-positive, the median survival was 30.5 months and 5-year survival 41% compared to 11.4 months and 9% 5-year survival for 77 patients whose DTH was never positive (P2 = 0.003). However, survival was even better for patients whose DTH test converted to positive compared to patients who were DTH-positive at baseline (median 37.5 vs 11.9 mos, P2 = 0.066).This patient-specific, cell culture-derived, autologous tumor cell vaccine induced anti-tumor immune reactivity that was associated with improved survival in patients with advanced cancer.

Interferon-alpha (IFN-alpha) has been safely given concurrently with radiation therapy (RT) in treating gliomas. As single agents, both IFN-alpha and cis-retinoic acid (CRA) have produced objective tumor regressions in patients with recurrent gliomas. In vitro, IFN-alpha2a and CRA enhance radiation therapy effects on glioblastoma cells more than either agent alone. This trial was conducted to determine the clinical effects of IFN-alpha2a and CRA when given concurrently with radiation therapy to patients with high-grade glioma. Newly diagnosed patients with high-grade glioma received IFN-alpha2a at a dosage of 3 to 6 million IU s.c. 4 times a day for 3 days per week and 1 mg/kg CRA by mouth 4 times a day for 5 days per week during the delivery of partial brain radiation therapy at 180 cGy x 33 fractions for 5 days per week for a total of 59.4 Gy during the 7-week period. Use of the antiepileptic phenytoin was prohibited after observing that the combination of IFN-alpha2a, CRA, and phenytoin was associated with a high rate of dermatologic toxicity not seen in a previous study with concurrent IFN-alpha2a and radiation therapy. Forty patients (26 men and 14 women) with a median age of 60 (range, 19 to 81 years) were enrolled between August 1996 and October 1998. Histopathologic diagnoses were glioblastoma multiforme or grade 4 anaplastic astrocytoma in 36 patients, and grade 3 anaplastic astrocytoma in 4 patients. Only 4 patients (10%) underwent a gross total resection of tumor prior to this therapy; 50% were asymptomatic when treatment was initiated. The planned 7-week course of concurrent therapy was completed by 75% of patients; 30% completed the 16-week course of IFN-alpha and CRA alone. At a median follow-up of 36 months, there were 37 deaths, with a median overall survival of 9.3 months and a 1-year survival rate of 42%. There was no improvement in survival compared with a similar group of 19 patients treated with concurrent IFN-alpha2a and radiation therapy in a previous trial. In the high-risk group of patients in the present study, concurrent treatment with IFN-alpha2a, CRA, and RT was feasible, but was not associated with a better outcome compared with a similar patient population treated with radiation therapy and IFN-alpha2a, or compared with radiation therapy alone in other trials.

Biochemical modulation of 5-Fluorouracil activity with Leucovorin has been well documented in colorectal cancer. Several studies have shown increased efficacy of 5-fluorouracil in combination with alpha interferon. We therefore initiated a phase II trial of dual modulation of 5-fluorouracil with leucovorin and alpha interferon to evaluate outcomes in patients with metastatic carcinoma of the colon.Patients with metastatic colon carcinoma with expected survival4 months and performance status of ECOGor = 2 were treated weekly with Leucovorin 400 mg i.v. followed by 5-FU 600 mg/m2 i.v. bolus. Alpha interferon 3-9 million units was administered subcutaneously every Monday, Wednesday and Friday. Patients were analyzed for toxicity, tumor response and survival.Sixteen patients with a median age of 66 years were treated. Three patients were not evaluable for response but were evaluable for toxicity. Grades 3 and 4 toxicities were neutropenia, diarrhea, mucositis, nausea and vomiting, fatigue, fever, asthenia and elevated hepatic enzymes. One patient died from complications associated with diverticulitis and neutropenia. Objective response rate was 23% (95% confidence interval 4-46%) and median survival was 11.5 months (95% confidence interval 6.3-19 months). Thirty-eight percent of the patients were alive at one year and 19% at two years.The combination of 5-fluorouracil, leucovorin and alpha interferon as administered in this phase II study did not result in enhanced response rate or survival. However this regimen was associated with considerable toxicity.

Background Interleukin-2 (IL-2) is an active agent for the treatment of renal cell carcinoma. In animal studies, polyethylene glycol conjugated (PEG) IL-2 was found to be effective in certain IL-2-resistant models. When bolus/infusion IL-2 was administered to approximate the pharmacokinetics of PEG-IL-2, resistance was also overcome in these models. Based on these observations, the National Bio-therapy Study Group (NBSG) previously had conducted a pilot study (NBSG 90-01) and then a phase I trial of a hybrid regimen of bolus IL-2 followed by continuous IL-2 (NBSG 91-04). Methods In the current study, NBSG 92-09, a phase II trial was conducted in patients with metastatic renal cell carcinoma using IL-2 at a dose of 36 MIU/m2 followed by a 72-hour continuous infusion of IL-2 at 18 MIU/m2 per day, so that over 3 days a total of 90 MIU/m2 of IL-2 were delivered; the same amount as previously given during 5 days of continuous intravenous (i.v.) IL-2 at 18 MIU/m2 per day. This was repeated every 2 weeks for 2 months, and then monthly for up to 4 months. Results Thirty-one patients with a median age of 62 years were enrolled in this trial. During the first 4 biweekly treatments, the percentages of planned IL-2 administered were 98% for 31 patients, 99% for 27, 98% for 23, and 99% for 20 patients. Toxicities were qualitatively the same as those seen with other IL-2 regimens. During the first 2 months, 4 patients ceased treatment because of rapidly progressive disease while 7 patients stopped because of toxicity; 5 of the 7 were > 65 years of age. At the time of formal reassessment after 2 months of treatment, 7 additional patients had progressive disease for a treatment failure rate of 55% prior to monthly maintenance therapy. There were two partial responses among 22 patients who had measurable disease for a response rate of 9% (1 to 29%, 95% CI). Median survival was 10.2 months and failure-free survival (FFS) 3.4 months for the entire group. Conclusion The response rate seen with this regimen is similar to those of other schedules of IL-2 requiring more prolonged hospitalization. This hybrid bolus/continuous infusion IL-2 schedule appears to be an equally effective and less expensive schedule of IL-2 administration than previously reported inpatient regimens. However, it is not likely that this regimen is superior to outpatient combination biotherapy regimens which are currently under investigation.

Meeting abstracts Treatment with high-dose Interleukin-2 (IL-2) has been associated with long-term survival in small proportion of metastatic melanoma patients. We recently reported a median survival of 15.6 months, and a 20% 5-year survival rate for 150 such patients who were hospitalized for high

Eltrapuldencel-T (CLBS20) consists of autologous dendritic cells loaded with antigens from irradiated, self-renewing, autologous tumor cells that potentially present the entire repertoire of unique patient-specific tumor-associated antigens resulting from nonsynonymous mutations in each patient's melanoma tumor cell line. In a single-arm phase 2 trial, metastatic melanoma patients treated with s.c. injections of CLBS20 had a 2-year overall survival (OS) of 73% (NCT00948480). In a randomized phase 2 trial (NCT00436930), 2-year OS was 72% compared to 31% for a tumor cell vaccine (TCV) consisting of irradiated cancer cells from an autologous tumor cell line. Mild local injection site reactions was the most common toxicity. This report focuses on 5-year follow up data from the randomized trial. During October 2007 to February 2011 42 patients were randomized 1:1 to receive CLBS20 or TCV. After resection of a metastatic tumor, if/when a cell line was established, patients were eligible for randomization if/when they were referred by their managing physician. Both products were mixed in 500 micrograms GM-CSF and injected s.c. weekly for three weeks, then monthly for up to 5 months. Cell lines were successfully established rapidly enough for possible clinical use for 78/183 (43%); 42/78 (54%) patients were referred for randomization. The median time from tumor submission to cell line success was 3.0 months, then 2.5 weeks for safety testing and documentation, then another 3.7 months to randomization. At the time of tumor harvest 24 patients were stage 4 and 18 were recurrent stage 3; at randomization 33 were stage 4 and 9 stage 3. Trends toward imbalances of baseline characteristics were biased against the CLBS20 arm (elevated LDH, detectable disease, brain metastases). There were no differences in tumor resection site, days in cell culture, or days to randomization. Because of leukapheresis and dendritic cell production for CLBS20, the median time from randomization to first dose was 43 days for CLBS20 vs 8 days for TCV. All patients were treated as randomized; survival was calculated from randomization date. At this analysis, 33 (79%) were dead and the 9 survivors had been followed 5 years. OS was higher in the CLBS20 arm: median 42.2 vs 19.9 months for all and 40.4 vs 16.9 for stage 4 patients, and in subsets defined by measurable disease, and serum LDH. The only variable associated with 3-year OS was randomization to CLBS20 (p = 0.018). A patient with refractory progressive measurable disease experienced a delayed complete response that was ongoing at 5 years. In an era before widespread use of anti-BRAF/anti-MEK and anti-checkpoint agents, CLBS20 monotherapy was associated with encouraging 5-year OS. Because of its unique mechanism of action, absence of toxicity, and apparent benefit regardless of tumor burden, CLBS20 is worthy of further evaluation as a monotherapy or in combination with other anti-melanoma therapies. Citation Format: Robert O. Dillman, Edward F. McClay, Thomas T. Amatruda, Carol DePriest, Denysha J. Carbonell, Andrew N. Cornforth. Randomized trial of dendritic vs tumor cell patient-specific vaccines: 5-year analysis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT105.

3090Background: CLBS20 is a patient-specific therapeutic vaccine consisting of autologous dendritic cells loaded with antigens from irradiated cells from an autologous tumor cell line. It potential...

Cancer is lethal because of metastatic spread, and is seldom curable, even in patients who can be rendered free of disease. Autologous, proliferating, self-renewing tumor cells (cancer stem cells and/or early progenitor cells), which are responsible for metastatic tumors, could be excellent sources of antigen for vaccines that could be used for the active specific immunotherapy of patients with advanced cancer. We have established proliferating pure tumor cell cultures from cancer samples, followed by further expansion for patient-specific therapeutic purposes. In clinical trials, patients were treated with a series of s.c. injections of irradiated autologous tumor cells (TCV), or autologous dendritic cells (DCV), loaded with antigens from their tumor cell line. Cell lines were successfully established for nearly half of patients, with the highest success rates in melanoma, renal cell, sarcoma, and glioblastoma. For patients with melanoma and renal cell, who were treated with TCV, observed 5-year survival rates were nearly three times longer than national figures. For patients with melanoma who were treated with DCV, the 5-year survival rate was five times greater than national estimates. In a randomized trial comparing DCV and TCV in patients with metastatic melanoma, at a median follow up of 2 years, survival is better in patients treated with DCV. Patient-specific active immunotherapy with antigens from autologous proliferating, self-renewing tumor cells is a feasible approach. Such treatment is associated with encouraging long-term survival rates, and results are superior in patients treated with DCV loaded with antigen from such cells. A higher success rate of establishing cancer stem cell cultures is needed, and additional clinical trials will be required to establish the clinical benefit.

A patient with metastatic melanoma who experienced a durable complete response after treatment with a patient-specific vaccine has been described in this article. This 59-year-old woman presented with cervical spine metastases and, within the year, had experienced local disease progression and, despite various therapies, metastases to the axilla, rectum, gall bladder, and multiple soft-tissue sites. She had previously received radiation therapy, combination chemotherapy, interleukin-2 plus interferon biotherapy, and gamma knife radiosurgery, and undergone multiple surgical resections. At the time vaccine therapy was initiated, she had multiple, new, measurable, soft-tissue metastases that were increasing in size. She was treated with a vaccine consisting of autologous dendritic cells incubated with irradiated tumor cells from an autologous tumor cell line and suspended in granulocyte-macrophage colony stimulating factor (GM-CSF), with subcutaneous injections once a week for 3 weeks and monthly for 5 months. There was evidence of disease regression by the completion of therapy. A few months later a complete response was documented by radiologic scans, and subsequently reconfirmed at 6-month intervals. She remains in complete remission2.5 years after starting the vaccine, and2 years after completing the vaccine, and survives4 years after her initial presentation with bone, bowel, and lymph node metastases. This is the first time she has been in a complete remission since her initial diagnosis. Patient-specific vaccines can sometimes induce durable complete regression of progressing soft-tissue melanoma metastases.

Between January 2001 and September 2007, we treated 54 metastatic melanoma patients with patient-specific tumor cell vaccines consisting of dendritic cells (DCS), derived from their peripheral blood cells that were cultured in interleukin (IL)-4 and granulocyte macrophage colony-stimulating factor (GM-CSF), which had phagocytosed irradiated autologous tumor cells from a continuously proliferating, self-renewing, autologus tumor cell (TC) culture. The loaded DCs were injected subcutaneously in 500 microg of GM-CSF weekly x three, and then monthly for 5 months, for a total of up to 8 injections. The 34 men and 20 women had a median age of 50.5 years; 32 had M1c (visceral metastases and/or elevated lactate dehydrogenase) as their most advanced disease stage. Overall, 83% had received other systemic therapies, including interferon-alpha (n = 20), biochemotherapy (n = 19), GM-CSF (n = 19), chemotherapy (n = 16), IL-2 (n = 13), and other investigational vaccines (n = 7). Patients received an average of 7.4 vaccinations. Treatment was well-tolerated, with most patients experiencing only mild local pruritus and/or erythema. A positive delayed-type hypersensitivity reaction to purified autologous tumor cells was observed at baseline in only 1 of 54 patients, compared to 12 of 54 following vaccination (p = 0.001). The projected 5-year survival rate is an impressive 54% at a median follow-up of 4.5 years (range, 2.4-7.4) for the 30 surviving patients. This survival was superior to that observed following vaccination with irradiated TC in 48 melanoma patients in a previous trial (64 versus 31 months, p = 0.016). This patient-specific vaccine warrants further investigation, based on its safety and encouraging survival rates. (NCI-V01-1646).

Seventy-four (74) patients with metastatic melanoma were treated with patient-specific vaccines derived from autologous tumor cell lines. Cryopreserved irradiated tumor cells were injected weekly for 3 weeks, then monthly for 5 months. At a median follow up6 years, the median event-free survival (EFS) was 4.5 months, with 13 patients alive and progression free 6-12 years later. Median overall survival (OS) was 20.5 months, with 29% 5-year OS. Tumor response rate was 9% among the 35 patients with evaluable disease who received at least 3 injections. Better survival was observed for patients who had minimal rather than clinically evident metastatic disease at the time vaccine therapy was initiated (5-yr OS 47% vs. 13%; p0.0001), received granulocyte-macrophage colony-stimulating factor and/or interferon gamma as an adjuvant (5-yr EFS 26% vs. 0%; p0.0001) or received an average of7 million cells for each of the first 3 injections, compared to those who received 7-11.9 million or12 million cells per injection (5-yr EFS OS 35% vs. 24%; p = 0.041 and p = 0.034). There was a trend toward better EFS for those who had a positive delayed type hypersensitivity (DTH) reaction to an intradermal injection of 1 million irradiated tumor cells at baseline, or converted to positive after 3 injections, compared to those whose DTH remained negative (5-yr EFS 39% vs. 18%; p = 0.159). This treatment approach is feasible, produces minimal toxicity, and is associated with longterm survival in a significant proportion of patients.

We conducted a phase II trial in metastatic renal cell cancer of outpatient subcutaneous (s.c.) interferon-alpha2b (IFN), followed by an inpatient hybrid schedule of bolus and continuous interleukin-2 (IL- 2).Treatment consisted of monthly IFN 10 MU/m(2) s.c. for 4 consecutive days, followed by 36 MIU/m(2) bolus IL-2, then 72-hour continuous intravenous (i.v.) infusion of 18 MIU/m(2) IL-2 per day. Between May 1997 and June 2000, 25 men and 11 women enrolled, with a median age of 57 years (range, 42-77), including 9 patients over 65. Prior treatment included nephrectomy (31), radiation (8), biotherapy (7), and chemotherapy (4). Sites of disease included 26 lung, 13 lymph node, 9 bone, 8 liver, 4 kidney, and 4 adrenal locations. Patients received an average of 3.1 treatment cycles (range, 1-6).There was 1 complete and 3 partial responses, for a response rate of 11% (3% to 27%; 95% confidence interval [CI]); 40% had stable disease. Median failure-free survival was 2.5 months; median overall survival was 15.0 months. The 1-, 2-, and 5-year survival rates were 53%, 30%, and 12%, respectively. Only 8 patients required a reduction in IL-2 dose. The most frequent grade 3 or 4 toxicities were 11% fatigue, 9% renal insufficiency, and 7% hypotension.Response and survival rates were similar to those seen in other multicenter trials using inpatient high-dose IL-2.

The Cancer Biotherapy Research Group conducted a clinical trial to verify encouraging reports of antitumor activity of autolymphocyte therapy.Patients with a variety of advanced solid malignancies underwent an initial leukapheresis procedure to collect about 5 x 10(9) autologous lymphocytes that were stimulated in vitro for 3 days with anti-CD3 monoclonal antibody in the presence of indomethicin and cis-retinoic acid to obtain media that was frozen in aliquots. This media contained significant amounts of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon-gamma, and IL6, but no IL-2. Subsequently patients underwent up to 6 monthly leukaphereses to collect 2-5 x 10(9) autologous lymphocytes that were incubated in vitro for 6 days in the cryopreserved media containing autologous lymphokines, resulting in a cell population enriched for noncytotoxic T-helper lymphocytes. These were administered intravenously monthly for up to 6 months with daily oral cimetidine at a dose of 600 mg po qid, which was given throughout the treatment period. Tumor response was assessed every 2 months.There were 47 patients (25 women and 22 men) with a median age of 55 years (range 31-79). One hundred seventy four treatments were delivered and were well tolerated. A mean of 2.05 +/- 1.46 (range 0.82-12.8 x 10(9)) cells were infused. Eighty-five percent received two or more doses; 19% received six doses. Objective tumor responses were observed in 1/15 renal cell, 1/13 colorectal, 0/6 breast, 0/5 lung, 0/2 gastric, 0/2 sarcoma, 0/1 pancreas, 0/1 prostate, 0/1 melanoma, and 0/1 eccrine. Forty-three patients have died. Median survival was 8.8 months, 1-year survival 35%, and 2-year survival 15%.This complex treatment program was feasible. Infusion of these cells was well tolerated. Some antitumor activity was seen in patients with renal cell cancer and colorectal cancer.

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Autologous melanoma cells that are proliferating and self-renewing in cell culture, have the phenotypic and functional characteristics of tumor stem cells. Such cells are responsible for invasiveness and metastases. They express not only a variety of melanoma-associated antigens, but also unique neoantigens associated with other mutations. Therefore such cells should provide excellent polyvalent antigenic targets for patient-specific vaccines. In successive trials in metastatic melanoma: [1] 74 patients injected with irradiated proliferating autologous tumor cells (TC) had a 20.5 month median overall survival (OS) and 29% 5-year OS (Cancer Biother Radiopharm 2007), [2] 54 patients injected with autologous dendritic cells that had been loaded with antigen from autologous proliferating tumor cells (DC/TC) had a 54% 5-year OS; (Cancer Biother Radiopharm 2009), [3] in a randomized trial survival was better for 18 patients treated with DC/TC compared to 24 TC-treated patients (J Immunother 2012). In the current analysis we examined the long-term benefits of DC/TC and TC in the subset of patients who, although they had experienced documented metastatic disease, had no detectable metastatic disease by physical examination or radiographic imaging at the time of vaccine treatment. OS was calculated from date of enrollment at the time of initiating vaccine in the various trials. Log rank tests were used to compare survival curves. In order to minimize potential bias, the study was limited to patients who received granulocyte-macrophage colony stimulating factor (GM-CSF) or interferon gamma (IFN-g) as adjuvants, and who received at least the first 3 planned weekly injections. There were 33 patients treated with DC/TC and 37 treated with TC. Median follow up was greater than 5 years for both groups with 8 DC/TC and 5 TC patients censored alive before 5 years; no patients were lost to follow up. There were no obvious prognostic differences between the treatment cohorts in terms of age, gender, or previous sites of metastases. Survival was longer in patients who received DC/TC, median not reached at 60 months vs 32 months, and 5-year OS 73% vs 43% (p=0.015). The survival for the TC cohort is consistent with the 40% to 45% 5-year survival rates reported for similar patients treated with BCG, BCG plus allogeneic tumor cells or melanoma peptide antigen immunotherapy following surgical resection of stage IV metastatic disease (Morton ASCO 2007, Tagawa Cancer 2006). The 73% 5-year survival rate for DC/TC suggests that autologous DC/TC may represent a superior adjunctive immunotherapy in such patients. (NCI-V01-1646 and [NCT00436930][1]) Supported by the Hoag Hospital Foundation and the Cancer Biotherapy Research Group. Citation Format: Robert O. Dillman, Carol DePriest, Robine Ellis, Cristina de Leon. 5-year survival for patients with metastatic melanoma who had no evidence of disease at time of treatment with patient specific tumor stem cell vaccines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 197. doi:10.1158/1538-7445.AM2014-197 [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00436930&atom=%2Fcanres%2F74%2F19_Supplement%2F197.atom

3090 Background: Autologous, proliferating, self-renewing cancer cells (tumor stem cells) express numerous tumor-associated antigens including unique neoantigens. They are an excellent antigen-sour...

Eighteen patients with advanced renal cancer were treated with 0.15 mg/kg/day floxuridine by continuous intravenous infusion for 14 days with 3 million IU/m2/day alpha interferon subcutaneously three times weekly. Treatment cycles were repeated every 28 days. Floxuridine dosages were escalated to a maximum of 0.2 mg/kg/day and alpha interferon dosages were escalated to a maximum of 6 million IU/m2/day depending on patient tolerability. A total of 49 treatment courses were administered with a median of 2.7 courses per patient. Of 14 assessable patients, there were no complete or partial responses. Eight patients (57%) had stabilization of disease. The median survival for patients with stable disease was 20.9 months and for all 18 patients was 7.2 months. Grades 3 and 4 toxicities included diarrhea (44%), nausea/vomiting (28%), mucositis (11%), fever (22%), and fatigue (50%). Dose-limiting toxicities were primarily gastrointestinal symptoms. There were no treatment-related deaths. This combination in the dose schedule used did not result in any significant objective tumor response but was associated with considerable toxicity.

Interleukin-2 (IL-2) is an active agent for the treatment of melanoma. In animal studies, polyethylene glycol conjugated (PEG) IL-2 was found to be effective in certain IL-2-resistant models. Bolus/infusional IL-2 administered to approximate the pharmacokinetics of PEG-IL-2 also overcame resistance in these models. Based on these observations, the Cancer Biotherapy Research Group (CBRG) [formerly the National Biotherapy Study Group (NBSG)] previously had conducted a pilot study and then a phase I trial of bolus IL-2 followed by continuous IL-2 (NBSG 90-01).In the current study, NBSG 92-09, a phase II trial was conducted using IL-2 at a dose of 36 MIU/m2 followed by a 72-hour continuous infusion of IL-2 at 18 MIU/m2/day, so that over 3 days a total of 90 MIU/m2 of IL-2 were delivered; the same amount as previously given during 5 days of continuous i.v. IL-2 at 18 MIU/m2/day. This schedule was repeated every 2 weeks for 2 months, and then monthly for up to 6 months.Twenty-two patients with metastatic melanoma were enrolled in this trial. Toxicities were qualitatively similar to those seen with other IL-2 regimens, but grade 3 and 4 toxicities were observed only in patients who received at least four cycles of treatment; only one patient went off study because of toxicity. For 18 patients with measurable disease, there were two complete and two partial responses in patients ages 32, 66, 72 and 83 years, for a response rate of 22% (6% to 48%; 95% confidence interval [Ci]). The median survival for all 21 evaluable patients enrolled in the trial was 8.5 months.The hybrid schedule of drug delivery in NBSG 92-09 allowed the same dose and intensity of IL-2 to be delivered over 3 days instead of 5 days, which resulted in fewer days of hospitalization and therefore decreased cost; but with no increase in toxicity and no decrease in efficacy in patients with metastatic melanoma.

2569 Background: Metastatic melanoma is seldom cured, even in patients who achieve a complete remission, because new sites of disease emerge. Autologous, proliferating, self-renewing tumor cells (putative tumor stem cells and/or early progenitor cells), are critical to establishment of new depots of metastatic cancer, and may be excellent sources of antigen for vaccines. These trials addressed the impact on survival from immunizing with antigens from such cells. Methods: Data was pooled from 3 successive phase II trials, all of which included patients with documented metastatic melanoma, who were treated in protocols that utilized antigens from cell cultures of autologous tumor cells. S.C. injections were given weekly for 3 weeks, then monthly for 5 months. 1992-2000: 74 patients were injected with irradiated tumor cells (TC). 2000-2006: 54 patients were injected with autologous dendritic cells (DC) that had been co-cultured with irradiated autologous tumor cells (NCI-V01-1646). 2007-2011: in a randomized phase II trial, 24 patients were injected with TC, and 18 with DC (NCT00436930). Results: The table summarizes overall survival (OS) in each trial. In the pooled analysis there were 98 TC and 72 DC patients. Characteristics were similar in terms of age (51, 52), male gender (62%, 62%), no evidence of disease at the time of treatment (46%, 47%), and presence of M1c visceral disease at the time of treatment (13%, 14%). OS was longer in patients treated with DC (median 63.1 vs 20.2 months, 5-year OS 51% vs 26%, p=0.0002 Mantle-Cox log-rank test). The difference in OS in the randomized trial is also significant (p=0.007). Conclusions: Patient-specific DC vaccines primed with antigens from autologous proliferating, self-renewing tumor cells are associated with encouraging long-term survival rates, and are superior to patient-specific TC vaccines in populations of patients who have been diagnosed with metastatic melanoma. [Table: see text]

8555 Background: Patient-specific vaccines utilizing proliferating tumor cells, or tumor stem cells, may be the ideal products for active specific immunotherapy. Methods: Eligible patients had recurrent or metastatic melanoma from which a cell line was established, expanded to 200 million cells, incubated with interferon-gamma, irradiated and cryopreserved. Autologous dendritic cells (DC) were derived from peripheral blood mononuclear cells cultured in IL-4 and GM-CSF. DC were incubated with the irradiated tumor cells, then cryopreserved in 20- million-cell aliquots, which were thawed, washed and suspended in 500 micrograms of GM-CSF for injection. Treatment consisted of s.c. injections weekly × 3, then monthly × 5 in a 2-stage phase II trial with two stratifications. Patients were characterized as having objectively measurable disease (OMD) or non-measurable disease (NMD). Plans were to enroll 30 to 80 patients: 15 to 40 with OMD, 15 to 40 with MD. Objectives were to determine safety, frequency of conversion of delayed type hypersensitivity (DTH) reactions to irradiated autologous tumor cells, objective response rate (ORR) using RECIST criteria, progression-free survival (PFS), overall survival (OS), and comparison to a historical control group. Results: Between January 2001 and April 2006, 55 patients were enrolled; 53 were eligible and evaluable. The 30 men and 23 women had a median age of 50 years; 15 had OMD and 38 NMD. Patients received an average of 7.4 vaccinations out of a possible 8. Treatment was well- tolerated. 25% had a positive tumor DTH test: 1 at baseline, 7 after 3 injections, 5 after 8 injections. ORR was 0/15. Follow up for the 39 surviving patients ranges from 7 to 67 months with a median of 30 months. Median PFS is 7.1 months with 24 patients remaining progression-free. Only 14 patients have died; median OS has not been reached. 5-year projected survival is 70%; 20 patients are alive 2.5 to 5.5 years from start of vaccine. OS is better than observed for 48 comparable patients that we treated previously in a trial with irradiated tumor cells without DC (p=0.016). Conclusion: This patient-specific vaccine approach is feasible, safe, associated with encouraging survival, and warrants further investigation. No significant financial relationships to disclose.

6685 Background: The alkylating agent cyclophosphamide (C), the purine nucleoside analogues pentostatin (P), and fludarabine (F) and the anti-CD20 monoclonal antibody rituximab (R) are active in CL...

In a randomized Phase II trial conducted in patients with metastatic melanoma, superior overall survival (p=0.007) was observed for 18 patients treated with vaccines that consisted of autologous dendritic cells loaded with antigens from irradiated autologous melanoma stem cells, (DC-TC, aka eltrapuldencel-T, NBS20 and CBLS20) compared to 24 patients treated with vaccines consisting of autologous irradiated melanoma stem cells (TC) [ClinicalTrials.gov NCT00436930].[1] Both vaccines were admixed with GM-CSF as an adjuvant. Tumor cell lines that served as the source of patient-specific tumor-associated antigens were derived from metastases resected from patients with stage IV or recurrent stage III melanoma. The treatment schedule consisted of weekly subcutaneous injections for 3 weeks, and then monthly for 5 months. The current analysis was undertaken to determine the treatment effects of DC-TC vs TC in each of the subsets defined by the pre-randomization stratifications that were based on whether patients had measurable or non-measurable disease as defined by RECIST, and whether their most advanced stage of disease at the time of randomization had been stage IV or recurrent stage III disease. At the time of this analysis 5 DC-TC and 3 TC patients had been followed for 5 years; 5 patients (3 TC and 2 DC-TC) were alive but followed less than 5 years (minimum 3.5 years); 29 were deceased. No patients were lost to follow up. The survival results are summarized in Table ​Table1.1. Although the numbers are small, DC-TC immunotherapy was associated with superior survival in each of the four different subsets defined by the stratification variables. Eltrapuldencel-T has moved forward into a pivotal Phase III trial sponsored by Caladrius BioSciences, Inc. Table 1