T. Dorval

Vaccination of metastatic melanoma patients with autologous dendritic cell (DC) derived-exosomes: results of thefirst phase I clinical trial

BackgroundDC derived-exosomes are nanomeric vesicles harboring functional MHC/peptide complexes capable of promoting T cell immune responses and tumor rejection. Here we report the feasability and safety of the first Phase I clinical trial using autologous exosomes pulsed with MAGE 3 peptides for the immunization of stage III/IV melanoma patients. Secondary endpoints were the monitoring of T cell responses and the clinical outcome.Patients and methodsExosomes were purified from day 7 autologous monocyte derived-DC cultures. Fifteen patients fullfilling the inclusion criteria (stage IIIB and IV, HLA-A1+, or -B35+ and HLA-DPO4+ leukocyte phenotype, tumor expressing MAGE3 antigen) were enrolled from 2000 to 2002 and received four exosome vaccinations. Two dose levels of either MHC class II molecules (0.13 versus 0.40 × 1014 molecules) or peptides (10 versus 100 μg/ml) were tested. Evaluations were performed before and 2 weeks after immunization. A continuation treatment was performed in 4 cases of non progression.ResultsThe GMP process allowed to harvest about 5 × 1014 exosomal MHC class II molecules allowing inclusion of all 15 patients. There was no grade II toxicity and the maximal tolerated dose was not achieved. One patient exhibited a partial response according to the RECIST criteria. This HLA-B35+/A2+ patient vaccinated with A1/B35 defined CTL epitopes developed halo of depigmentation around naevi, a MART1-specific HLA-A2 restricted T cell response in the tumor bed associated with progressive loss of HLA-A2 and HLA-BC molecules on tumor cells during therapy with exosomes. In addition, one minor, two stable and one mixed responses were observed in skin and lymph node sites. MAGE3 specific CD4+ and CD8+ T cell responses could not be detected in peripheral blood.ConclusionThe first exosome Phase I trial highlighted the feasibility of large scale exosome production and the safety of exosome administration.

Neoadjuvant versus adjuvant chemotherapy in premenopausal patients with tumours considered too large for breast conserving surgery: Preliminary results of a randomised trial: S6

The aim of this study was to assess a potential advantage in survival by neoadjuvant as compared to adjuvant chemotherapy. 414 premenopausal patients with T2-T3 N0-N1 M0 breast cancer were randomised to receive either four cycles of neoadjuvant chemotherapy (cyclophosphamide, doxorubicin, 5-fluorouracil), followed by local-regional treatment (group I) or four cycles of adjuvant chemotherapy after primary irradiation +/- surgery (group II). Surgery was limited to those patients with a persisting mass after irradiation, and aimed to be as conservative as possible. 390 patients were evaluable. With a median follow-up of 54 months, we observed a statistically significant difference (P = 0.039) in survival in favour of the neoadjuvant chemotherapy group. A similar trend was seen when the time to metastatic recurrence was evaluated (P = 0.09). At this stage, no difference in disease-free interval or local recurrence between these two groups could be observed. The mean total dose of chemotherapy administered was similar in both groups. On average, group I had more intensive chemotherapy regimes (doxorubicin P = 0.02) but fewer treatment courses (P = 0.008) as compared to the treated patients in group II. Haematological tolerance was reduced when chemotherapy succeeded to exclusive irradiation. Breast conservation was identical for both groups at the end of primary treatment (82 and 77% for groups I and II, respectively). Of the 191 evaluable patients in the neoadjuvant treatment arm, 65% had an objective response (> 50% regression) following four cycles of chemotherapy. The objective response rate to primary irradiation (55 Gy) was 85%. Improved survival figures in the neoadjuvant treatment arm could be the result of the early initiation of chemotherapy, but we cannot exclude that this difference might be attributable to a slightly more aggressive treatment. So far, the trend in favour of decreased metastases was not statistically significant. The local control appeared similar in both subgroups.

A monoclonal cytolytic T-lymphocyte response observed in a melanoma patient vaccinated with a tumor-specific antigenic peptide encoded by gene MAGE-3

Vaccination of melanoma patients with tumor-specific antigens recognized by cytolytic T lymphocytes (CTL) produces significant tumor regressions in a minority of patients. These regressions appear to occur in the absence of massive CTL responses. To detect low-level responses, we resorted to antigenic stimulation of blood lymphocyte cultures in limiting dilution conditions, followed by tetramer analysis, cloning of the tetramer-positive cells, and T-cell receptor (TCR) sequence analysis of the CTL clones that showed strict specificity for the tumor antigen. A monoclonal CTL response against a MAGE-3 antigen was observed in a melanoma patient, who showed partial rejection of a large metastasis after treatment with a vaccine containing only the tumor-specific antigenic peptide. Tetramer analysis after in vitro restimulation indicated that about 1/40,000 postimmunization CD8+ blood lymphocytes were directed against the antigen. The same TCR was present in all of the positive microcultures. TCR evaluation carried out directly on blood lymphocytes by PCR amplification led to a similar frequency estimate after immunization, whereas the TCR was not found among 2.5 × 106 CD8+ lymphocytes collected before immunization. Our results prove unambiguously that vaccines containing only a tumor-specific antigenic peptide can elicit a CTL response. Even though they provide no information about the effector mechanisms responsible for the observed reduction in tumor mass in this patient, they would suggest that low-level CTL responses can initiate tumor rejection.

Results of interleukin-2-based treatment in advanced melanoma: a case record-based analysis of 631 patients.

PURPOSE In patients with stage IV melanoma, durable responses have been reported with treatment regimens that involve high-dose interleukin-2 (IL-2). We analyze long-term results of 631 melanoma patients from 12 institutions who had received IL-2 alone, in combination with interferon alfa 2a or 2b (IFNalpha), or with cytotoxic drugs. METHODS Case records that contained pretreatment parameters, response data, and updated survival information were collected. After univariate analysis, the multivariate evaluation of the impact of pretreatment parameters on response and survival was performed by logistic regression and Coxs regression, respectively. RESULTS Patients were divided into four groups according to treatment: IL-2 alone (n=117), IL-2 and chemotherapy (n=49), IL-2 and IFNalpha (n=153), and IL-2, chemotherapy, and IFNalpha (n=312). The median survival of all patients was 10.5 months and the 2- and 5-year survival rates were 19.9% and 10.4%, respectively. Independent prognostic factors for response and survival were entirely different, treatment group being the only significant factor for response, and serum lactate dehydrogenase (LDH), metastatic site, and performance predicting survival. The addition of IFNalpha to IL-2 was associated with prolonged survival, but the effect of additional chemotherapy was less obvious. CONCLUSION Serum LDH, metastatic site, and performance status are useful stratification factors for randomized trials in metastatic melanoma. The improved long-term survival rates observed in melanoma patients treated with IL-2/IFNalpha-containing regimens are notable in contrast to the reported 5-year survival rates of 2% to 6% achieved with chemotherapy, but because selection bias cannot be ruled out, the impact of IL-2, as well as all other components of the treatment regimens, on survival needs to be confirmed in prospective randomized trials.

Tumoral and Immunologic Response After Vaccination of Melanoma Patients With an ALVAC Virus Encoding MAGE Antigens Recognized by T Cells

PURPOSE To evaluate the toxicity, antitumoral effectiveness, and immunogenicity of repeated vaccinations with ALVAC miniMAGE-1/3, a recombinant canarypox virus containing a minigene encoding antigenic peptides MAGE-3(168-176) and MAGE-1(161-169), which are presented by HLA-A1 and B35 on tumor cells and can be recognized by cytolytic T lymphocytes (CTLs). MATERIALS AND METHODS The vaccination schedule comprised four sequential injections of the recombinant virus, followed by three booster vaccinations with the MAGE-3(168-176) and MAGE-1(161-169) peptides. The vaccines were administered, both intradermally and subcutaneously, at 3-week intervals. RESULTS Forty patients with advanced cancer were treated, including 37 melanoma patients. The vaccines were generally well tolerated with moderate adverse events, consisting mainly of transient inflammatory reactions at the virus injection sites. Among the 30 melanoma patients assessable for tumor response, a partial response was observed in one patient, and disease stabilization in two others. The remaining patients had progressive disease. Among the patients with stable or progressive disease, five showed evidence of tumor regression. A CTL response against the MAGE-3 vaccine antigen was detected in three of four patients with tumor regression, and in only one of 11 patients without regression. CONCLUSION Repeated vaccination with ALVAC miniMAGE-1/3 is associated with tumor regression and with a detectable CTL response in a minority of melanoma patients. There is a significant correlation between tumor regression and CTL response. The contribution of vaccine-induced CTL in the tumor regression process is discussed in view of the immunologic events that could be analyzed in detail in one patient.

BREAST TUMOUR RESPONSE TO PRIMARY CHEMOTHERAPY PREDICTS LOCAL AND DISTANT CONTROL AS WELL AS SURVIVAL

The purpose of the present paper was to evaluate correlations between clinical response to chemotherapy and outcome in a subgroup analysis of premenopausal patients with tumours considered too large for breast conserving surgery, treated with primary chemotherapy (n = 200) from a previously published trial (Scholl S.M., Fourquet A., Asselain B, et al. Eur J Cancer 1994, 30A, 645-652). Objective response rates amounted to 65% following four courses. In a multivariate Cox regression analysis, comparing seven parameters, the following variables were associated with poor survival: clinically involved nodes [N1b:RR: 2.7 (95% CI 1.3-5.3)], the failure to respond to chemotherapy [D:RR: 2.62 (95% CI 1.3-5)] and a raised S phase fraction [SPF > 5%: RR: 2.4 (95% CI 1.2-5)]. Parameters associated with increased metastatic recurrence rates, by order of entry in the model, were: young age [< 35: RR: 2.46 (95% CI 1.2-5)], large clinical tumour size [T3: RR: 2.02 (95% CI 1.2-3.4)], poor histological grade (SBR III: RR: 1.93 (95% CI 1.1-3.3)] and the failure to respond to chemotherapy [D: RR: 1.91 (95% CI 1-3.4)]. The assessment of both tumour cell proliferation rates as well as possibly drug resistance markers (although not available in the present study) should be helpful in selecting patients likely to benefit from intensified chemotherapy regimens. The most accurate predictor of response in the present study appeared to be the response to chemotherapy treatment itself.

Phase 1/2 study of subcutaneous and intradermal immunization with a recombinant MAGE-3 protein in patients with detectable metastatic melanoma

The purpose of this phase 1/2 study was to evaluate toxicity, tumor evolution and immunologic response following administration of a fixed dose of a recombinant MAGE‐3 protein by subcutaneous and intradermal routes in the absence of immunologic adjuvant. Thirty‐two patients with detectable metastatic melanoma expressing gene MAGE‐3 were included and 30 received at least one injection with a fixed dose of a ProtD‐MAGE‐3 fusion protein. The immunization schedule included 6 intradermal and subcutaneous injections at 3‐week intervals. Afterward, patients without major tumor progression who required other treatments received additional vaccinations at increasing time intervals. The vaccine was generally well tolerated. Among the 26 patients who received at least 4 vaccinations, we observed 1 partial response and 4 mixed responses. For these 5 responding patients, time to progression varied from 3.5 to 51+ months. An anti‐MAGE‐3 CD4 T‐lymphocyte response was detected in 1 out of the 5 responding patients. The majority of patients had no anti‐MAGE‐3 antibody response. The clinical and immunologic responses generated by the vaccine are rather limited. Nevertheless, given the potential antitumor efficacy and the very mild toxicity of vaccinations, further studies combining MAGE proteins and/or peptides with potent immunologic adjuvants are warranted, not only in metastatic melanoma, but also in the adjuvant setting.

Selection of Immunostimulant AS15 for Active Immunization With MAGE-A3 Protein: Results of a Randomized Phase II Study of the European Organisation for Research and Treatment of Cancer Melanoma Group in Metastatic Melanoma

PURPOSE Active immunization against the tumor-specific MAGE-A3 antigen is followed by a few but impressive and durable clinical responses. This randomized phase II trial evaluated two different immunostimulants combined with the MAGE-A3 protein to investigate whether a more robust and persistent immune response could be associated with increased clinical benefit. PATIENTS AND METHODS Patients with MAGE-A3-positive stage III or IV M1a melanoma were randomly assigned to receive the MAGE-A3 protein combined either with AS02B or with AS15 immunostimulant. Clinical end points were toxicity and rates of objective clinical responses, progression-free survival (PFS), and overall survival (OS). RESULTS Seventy-five patients were treated, with 36 eligible patients per arm. Both treatments were well tolerated. In the AS15 arm, four objective responses were observed (three complete responses and one partial response) versus one partial response in the AS02B arm. In the AS15 and AS02B arms, the PFS rates after 6 months were 25% and 14%, respectively; and the median OS times were 33 months and 19.9 months, respectively, with a median observation period of 48 months. Antibodies against MAGE-A3, found in all patients, showed three-fold higher titers in the AS15 arm. The anti-MAGE-A3 cellular response was also more pronounced in the AS15 arm. CONCLUSION In the MAGE-A3+AS15 arm, clinical activity was higher and the immune response more robust. Therefore, the AS15 immunostimulant was selected for combination with the MAGE-A3 protein in phase III trials.

Serum interleukin 6 and C-reactive protein levels correlate with resistance to IL-2 therapy and poor survival in melanoma patients.

Interleukin 6 and C-reactive protein (CRP) were determined prior to IL-2 therapy in sera from metastatic melanoma patients. Patients with elevated serum IL-6 (> 20 pg ml-1) and/or CRP (> 10 mg l-1) levels were associated with resistance to IL-2 therapy. A correlation between high serum IL-6 levels and a shorter median survival was also observed.

Meningeal Carcinomatosis in Patients with Breast Carcinoma Clinical Features, Prognostic Factors, and Results of a High- Dose Intrathecal Methotrexate Regimen

This retrospective study evaluates the results of a regimen of high‐dose intrathecal methotrexate and the prognostic factors for response in patients with meningeal metastases from breast carcinoma.