CYAD-01, an autologous NKG2D-based CAR T-cell therapy, in relapsed or refractory acute myeloid leukaemia and myelodysplastic syndromes or multiple myeloma (THINK): haematological cohorts of the dose escalation segment of a phase 1 trial.

BACKGROUND: CYAD-01 is an autologous chimeric antigen receptor (CAR) T-cell product based on the natural killer (NK) group 2D (NKG2D) receptor, which binds eight ligands that are overexpressed in a wide range of haematological malignancies but are largely absent on non-neoplastic cells. Initial clinical evaluation of a single infusion of CYAD-01 at a low dose in patients with relapsed or refractory acute myeloid leukaemia, myelodysplastic syndromes, and multiple myeloma supported the feasibility of the approach and prompted further evaluation of CYAD-01. The aim of the present study was to determine the safety and recommended phase 2 dosing of CYAD-01 administered without preconditioning or bridging chemotherapy. METHODS: The multicentre THINK study was an open-label, dose-escalation, phase 1 study for patients with relapsed or refractory acute myeloid leukaemia, myelodysplastic syndromes, or multiple myeloma, after at least one previous line of therapy. Patients were recruited from five hospitals in the USA and Belgium. The dose-escalation segment evaluated three dose levels: 3 × 108 (dose level one), 1 × 109 (dose level two), and 3 × 109 (dose level three) cells per infusion with a 3 + 3 Fibonacci study design using a schedule of three infusions at 2-week intervals followed by potential consolidation treatment consisting of three additional infusions. The occurrence of dose-limiting toxicities post-CYAD-01 infusion was assessed as the primary endpoint in the total treated patient population. The trial was registered with ClinicalTrials.gov, NCT03018405, and EudraCT, 2016-003312-12, and has been completed. FINDINGS: Between Feb 6, 2017, and Oct 9, 2018, 25 patients were registered in the haematological dose-escalation segment. Seven patients had manufacturing failure for insufficient yield and two had screening failure. 16 patients were treated with CYAD-01 (three with multiple myeloma and three with acute myeloid leukaemia at dose level one; three with acute myeloid leukaemia at dose level two; and six with acute myeloid leukaemia and one with myelodysplastic syndromes at dose level three). Median follow-up was 118 days (IQR 46-180). Seven patients (44%) had grade 3 or 4 treatment-related adverse events. In total, five patients (31%) had grade 3 or 4 cytokine release syndrome across all dose levels. One dose-limiting toxicity of cytokine release syndrome was reported at dose level three. No treatment-related deaths occurred, and the maximum tolerated dose was not reached. Three (25%) of 12 evaluable patients with relapsed or refractory acute myeloid leukaemia or myelodysplastic syndromes had an objective response. Among responders, two patients with acute myeloid leukaemia proceeded to allogeneic haematopoietic stem-cell transplantation (HSCT) after CYAD-01 treatment, with durable ongoing remissions (5 and 61 months). INTERPRETATION: Treatment with a multiple CYAD-01 infusion schedule without preconditioning is well tolerated and shows anti-leukaemic activity, although without durability outside of patients bridged to allogeneic HSCT. These phase 1 data support the proof-of-concept of targeting NKG2D ligands by CAR T-cell therapy. Further clinical studies with NKG2D-based CAR T-cells are warranted, potentially via combinatorial antigen targeted approaches, to improve anti-tumour activity. FUNDING: Celyad Oncology.

Expression of tumor-associated antigens in breast cancer subtypes.

OBJECTIVES: Tumor-associated antigens (TAAs) are frequently overexpressed in several cancer types. The aim of this study was to investigate the expression of TAAs in breast cancer. MATERIAL AND METHODS: A total of 250 selected invasive breast cancers including 50 estrogen receptor (ER)-positive (Luminal B like), 50 triple-negative (TN), 50 ER-positive lobular type, 50 ER- and progesterone receptor (PgR)-positive (Luminal A like) and 50 cerbB2-positive breast cancers, were assessed for New York esophageal squamous cell carcinoma-1 (NY-ESO-1), Wilms tumor antigen (WT-1) and PReferentially expressed Antigen of MElanoma (PRAME) antigen expression by immunohistochemistry (IHC). RESULTS: A significantly higher expression of cancer testis (CT)-antigens NY-ESO-1 and WT-1 antigen was detected in TN breast cancers compared with ER-positive tumors. NY-ESO-1 overexpression (score 2 + and 3+) assessed by monoclonal and polyclonal antibodies was detected in 9 (18%) TN cancers as compared to 2 (4%) ER-positive tumors (p = 0.002). WT1 over-expression (score 2 + and 3+) was confirmed in 27 (54%) TN tumor samples as compared to 6 (12%) ER-positive (p < 0.0001). PRAME over-expression (score 2 + and 3+) was detected in 8 (16%) HER2 positive tumor samples as compared to no TN and ER-positive cancers (p = 0.0021). CONCLUSIONS: NY-ESO-1 and WT1 antigens are overexpressed in TN breast cancers. Because of the limited therapeutic options for this patient subgroup, CT antigen-based vaccines might prove to be useful for patients with this phenotype of breast cancer.

Chimeric Antigen Receptor-T Cells for Targeting Solid Tumors: Current Challenges and Existing Strategies.

Chimeric antigen receptor-T cells (CAR-Ts) are an exciting new cancer treatment modality exemplified by the recent regulatory approval of two CD19-targeted CAR-T therapies for certain B cell malignancies. However, this success in the hematological setting has yet to translate to a significant level of objective clinical responses in the solid tumor setting. The reason for this lack of translation undoubtedly lies in the substantial challenges raised by solid tumors to all therapies, including CAR-T, that differ from B cell malignancies. For instance, intravenously infused CAR-Ts are likely to make rapid contact with cancerous B cells since both tend to reside in the same vascular compartments within the body. By contrast, solid cancers tend to form discrete tumor masses with an immune-suppressive tumor microenvironment composed of tumor cells and non-tumor stromal cells served by abnormal vasculature that restricts lymphocyte infiltration and suppresses immune function, expansion, and persistence. Moreover, the paucity of uniquely and homogeneously expressed tumor antigens and inherent plasticity of cancer cells provide major challenges to the specificity, potency, and overall effectiveness of CAR-T therapies. This review focuses on the major preclinical and clinical strategies currently being pursued to tackle these challenges in order to drive the success of CAR-T therapy against solid tumors.

Phase I Trial of Autologous CAR T Cells Targeting NKG2D Ligands in Patients with AML/MDS and Multiple Myeloma.

NKG2D ligands are widely expressed in solid and hematologic malignancies but absent or poorly expressed on healthy tissues. We conducted a phase I dose-escalation study to evaluate the safety and feasibility of a single infusion of NKG2D-chimeric antigen receptor (CAR) T cells, without lymphodepleting conditioning in subjects with acute myeloid leukemia/myelodysplastic syndrome or relapsed/refractory multiple myeloma. Autologous T cells were transfected with a γ-retroviral vector encoding a CAR fusing human NKG2D with the CD3ζ signaling domain. Four dose levels (1 × 106-3 × 107 total viable T cells) were evaluated. Twelve subjects were infused [7 acute myeloid leukemia (AML) and 5 multiple myeloma]. NKG2D-CAR products demonstrated a median 75% vector-driven NKG2D expression on CD3+ T cells. No dose-limiting toxicities, cytokine release syndrome, or CAR T cell-related neurotoxicity was observed. No significant autoimmune reactions were noted, and none of the ≥ grade 3 adverse events were attributable to NKG2D-CAR T cells. At the single injection of low cell doses used in this trial, no objective tumor responses were observed. However, hematologic parameters transiently improved in one subject with AML at the highest dose, and cases of disease stability without further therapy or on subsequent treatments were noted. At 24 hours, the cytokine RANTES increased a median of 1.9-fold among all subjects and 5.8-fold among six AML patients. Consistent with preclinical studies, NKG2D-CAR T cell-expansion and persistence were limited. Manufactured NKG2D-CAR T cells exhibited functional activity against autologous tumor cells in vitro, but modifications to enhance CAR T-cell expansion and target density may be needed to boost clinical activity.

Association of homogeneous inflamed gene signature with a better outcome in patients with metastatic melanoma treated with MAGE-A3 immunotherapeutic.

PURPOSE: This study assessed clinical activity, safety and immunogenicity of MAGE-A3 immunotherapeutic in patients with MAGE-A3-positive metastatic melanoma. PATIENTS AND METHODS: In this open-label, multicentre, uncontrolled, Phase II study (ClinicalTrials.gov NCT00896480), patients received ≤24 doses of MAGE-A3 immunotherapeutic (4-cycle schedule). At screening, two skin lesions were biopsied for MAGE-A3 expression analysis and presence/absence of a previously identified gene signature (GS) associated with favourable clinical outcome. Clinical activity was assessed in terms of clinical response, time-to-treatment failure (TTF) and progression-free survival (PFS). Adverse events (AEs) and serious AEs (SAEs) were recorded. MAGE-A3-specific immune responses were assessed. Clinical activity and immunogenicity were analysed overall and separately in patients with 2/2 (GS+/+), 1/2 (GS+/-) or 0/2 (GS-/-) biopsies presenting GS. RESULTS: Of 49 screened patients, 32 had MAGE-A3-positive tumours; 24 (8 GS+/+, 8 GS+/-, 8 GS-/-) were treated. Two complete (GS+/+ patients) and two partial responses (one GS+/+, one GS+/-) were reported; of note, one of the two complete responses was unlikely to be related to the study treatment. Median TTF and PFS were 14.8 and 7.2 months for GS+/+, 2.3 and 2.8 months for GS+/- and 2.4 and 2.9 months for GS-/- patients. Three grade 3 AEs and two SAEs unrelated to treatment were reported. All patients were seropositive for MAGE-A3 antibodies on vaccination with no differences between the different GS profiles. MAGE-A3-specific CD4+ and CD8+ T cell immunogenicity was detected; 12/16 (75.0%) of patients presented CD4+ T cell responses. CONCLUSION: Treatment with MAGE-A3 immunotherapeutic showed signs of clinical activity in GS+/+ patients. Treatment was well tolerated and immunogenic. No differences in immune responses according to GS status were observed. TRIAL REGISTRATION NUMBER: NCT00896480 (Results).

Celyad's novel CAR T-cell therapy for solid malignancies.

Celyad recently initiated several clinical trials with the CYAD-01 product, a natural killer group 2D (NKG2D)-based chimeric antigen receptor (CAR), in both solid and hematologic tumor types. This review discusses the unique properties of CYAD-01, expecting to provide a new paradigm to fight against solid tumors.

Safety and immunogenicity of MAGE-A3 cancer immunotherapeutic with dacarbazine in patients with MAGE-A3-positive metastatic cutaneous melanoma: an open phase I/II study with a first assessment of a predictive gene signature.

BACKGROUND: We assessed safety, immunogenicity and clinical activity of recombinant MAGE-A3 antigen combined with AS15 immunostimulant (MAGE-A3 immunotherapeutic) in association with dacarbazine in patients with metastatic melanoma. METHODS: In this open-label, phase I/II, uncontrolled multicentre trial conducted in Belgium and France, patients with MAGE-A3-positive melanoma received up to 24 doses of MAGE-A3 immunotherapeutic (four cycles) coadministered with eight doses of dacarbazine. Adverse events (AE) were recorded until 31 days postvaccination, and serious AEs (SAE), until 30 days following the last dose. MAGE-A3-specific antibodies were measured by ELISA. Clinical activity of MAGE-A3 immunotherapeutic was assessed in patients positive/negative for previously identified gene signature (GS) associated with clinical outcome. RESULTS: Forty-eight patients were enrolled and treated (32 GS+, 15 GS-, 1 unknown GS status); two patients completed the study. All patients reported AEs, the most common were 'general disorders and administration site conditions' (94%). Treatment-related AEs were reported by 85% of patients; the most common was pain at injection site (38%). Sixteen SAEs were reported by 21% of patients; two were considered as treatment related (neutropenia and thrombocytopenia; grade 4). Postdose 4, all patients were seropositive for MAGE-A3-specific antibodies, with a geometric mean titre of 2778.7 ELISA units (EU)/mL (95% CI 1638.3 to 4712.8). One complete and three partial responses were reported (only in GS+ patients). Median overall survival was 11.4 months for GS+ and 5.3 months for GS- patients. CONCLUSION: Although this trial shows poor results compared with the new results with checkpoint inhibitors, it gives an interesting insight in rapidly developing fields like combinations of immunotherapy and chemotherapy, new generation vaccines and the use of gene profile as a predictive marker. TRIAL REGISTRATION NUMBER: NCT00849875.

Study protocol for THINK: a multinational open-label phase I study to assess the safety and clinical activity of multiple administrations of NKR-2 in patients with different metastatic tumour types.

INTRODUCTION: NKR-2 are autologous T cells genetically modified to express a chimeric antigen receptor (CAR) comprising a fusion of the natural killer group 2D (NKG2D) receptor with the CD3ζ signalling domain, which associates with the adaptor molecule DNAX-activating protein of 10 kDa (DAP10) to provide co-stimulatory signal upon ligand binding. NKG2D binds eight different ligands expressed on the cell surface of many tumour cells and which are normally absent on non-neoplastic cells. In preclinical studies, NKR-2 demonstrated long-term antitumour activity towards a breadth of tumour indications, with maximum efficacy observed after multiple NKR-2 administrations. Importantly, NKR-2 targeted tumour cells and tumour neovasculature and the local tumour immunosuppressive microenvironment and this mechanism of action of NKR-2 was established in the absence of preconditioning. METHODS AND ANALYSIS: This open-label phase I study will assess the safety and clinical activity of NKR-2 treatment administered three times, with a 2-week interval between each administration in different tumour types. The study will contain two consecutive segments: a dose escalation phase followed by an expansion phase. The dose escalation study involves two arms, one in solid tumours (five specific indications) and one in haematological tumours (two specific indications) and will include three dose levels in each arm: 3×108, 1×109 and 3×109 NKR-2 per injection. On the identification of the recommended dose in the first segment, based on dose-limiting toxicity occurrences, the study will expand to seven different cohorts examining the seven different tumour types separately. Clinical responses will be determined according to standard Response Evaluation Criteria In Solid Tumors (RECIST) criteria for solid tumours or international working group response criteria in haematological tumours. ETHICS APPROVAL AND DISSEMINATION: Ethical approval has been obtained at all sites. Written informed consent will be taken from all participants. The results of this study will be disseminated through presentation at international scientific conferences and reported in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: NCT03018405, EudraCT 2016-003312-12; Pre-result.

The prevalence of expression of MAGE-A3 and PRAME tumor antigens in East and South East Asian non-small cell lung cancer patients.

INTRODUCTION: Treatment of non-small cell lung cancer (NSCLC) is an important and often unmet medical need regardless of the disease stage at the time of first diagnosis. Antigen-specific immunotherapy may be a feasible therapeutic option if tumor associated antigens (TAAs) that can be targeted by the patient's immune system are identified. The study objective (NCT01837511) was to investigate the expression rates of MAGE-A3 and PRAME in tumors from East Asian NSCLC patients, and the associations between TAA expression and clinico-pathologic patient characteristics. METHODS: Archived formalin-fixed paraffin-embedded tumor tissue specimens were tested for MAGE-A3 and PRAME expression by quantitative reverse transcription polymerase chain reaction. Exploratory analyses of the impact of patient and tumor characteristics on antigen expression were performed by multivariate logistic regression analyses. RESULTS: A total of 377 specimens were tested and a valid expression result was obtained for 86.5% and 92.6% for MAGE-A3 and PRAME, respectively. Of the specimens with valid test results, 26.4% expressed MAGE-A3, 49.9% PRAME, 20.0% both and 57.5% expressed at least one TAA. The same pattern of associations between antigen expression and patient and tumor characteristics was found for both TAAs: higher rates of antigen-positive tumors were found in squamous cell carcinomas compared to adenocarcinomas, and for smokers compared to non-smokers. CONCLUSIONS: Expression of MAGE-A3 and PRAME suggests an association with tumor histology and the patient's smoking status. The rates of TAA-positive tumors found in these East and South East Asian NSCLC patients indicate that both antigens may serve as targets for antigen-specific immunotherapies.

Safety and Immunogenicity of the PRAME Cancer Immunotherapeutic in Patients with Resected Non-Small Cell Lung Cancer: A Phase I Dose Escalation Study.

INTRODUCTION: Adjuvant platinum-based chemotherapy is standard treatment for surgically resected stage II to IIIA NSCLC, but the relapse rate is high. The preferentially expressed antigen of melanoma (PRAME) tumor antigen is expressed in two-thirds of NSCLC and offers an attractive target for antigen-specific immunization. A phase I dose escalation study assessed the safety and immunogenicity of a PRAME immunotherapeutic consisting of recombinant PRAME plus proprietary immunostimulant AS15 in patients with surgically resected NSCLC (NCT01159964). METHODS: Patients with PRAME-positive resected stage IB to IIIA NSCLC were enrolled in three consecutive cohorts to receive up to 13 injections of PRAME immunotherapeutic (recombinant PRAME protein dose of 20 µg, 100 µg, or 500 µg, with a fixed dose of AS15). Adverse events, predefined dose-limiting toxicity, and the anti-PRAME humoral response (measured by enzyme-linked immunosorbent assay) were coprimary end points. Anti-PRAME cellular responses were assessed. RESULTS: A total of 60 patients were treated (18 received 20 µg of PRAME, 18 received 100 µg of PRAME, and 24 received 500 µg of PRAME). No dose-limiting toxicity was reported. Adverse events considered by the investigator to be causally related to treatment were grade 1 or 2, and most were injection site reactions or fever. All patients had detectable anti-PRAME antibodies after four immunizations. The percentages of patients with PRAME-specific CD4-positive T cells were higher at the dose of 500 µg compared with lower doses. No predefined CD8-positive T-cell responses were detected. CONCLUSION: The PRAME immunotherapeutic had an acceptable safety profile. All patients had anti-PRAME humoral responses that were not dose related, and 80% of those treated at the highest dose showed a cellular immune response. The dose of 500 µg was selected. However, further development was stopped after negative results with a similar immunotherapeutic in patients with NSCLC.

A non-randomized dose-escalation Phase I trial of a protein-based immunotherapeutic for the treatment of breast cancer patients with HER2-overexpressing tumors.

This Phase I dose-escalation study (NCT00058526) assessed the safety and immunogenicity of an anti-cancer immunotherapeutic (recombinant HER2 protein (dHER2) combined with the immunostimulant AS15) in patients with early-stage HER2-overexpressing breast cancer (BC). Sixty-one trastuzumab-naive patients with stage II-III HER2-positive BC received the dHER2 immunotherapeutic after surgical resection and adjuvant therapy. They were allocated into four cohorts receiving different doses of dHER2 (20, 100, 500 µg) combined with a fixed AS15 dose. Safety and immunogenicity (dHER2-specific antibody responses) were assessed. After completing the immunization schedule (three or six doses over 14 weeks) and a six-month follow-up, the patients were followed for 5 years for late toxicity, long-term immunogenicity, and clinical status. The immunizations were well tolerated, and increasing doses of dHER2 had no impact on the frequency or severity of adverse events. Few late toxicities were reported, and after 5 years 45/54 patients (83.3 %) were still alive, while 28/45 (62 %) with known disease status were disease free. Regarding the immunogenicity of the compound, a positive association was found between the dHER2 dose, the immunization schedule, and the prevalence of dHER2-specific humoral responses. Among the patients receiving the most intense immunization schedule with the highest dHER2 dose, 6/8 maintained their dHER2-specific antibody response 5 years after immunization. The dHER2 immunotherapeutic had an acceptable safety profile in early HER2-positive BC patients. dHER2-specific antibody responses were induced, with the rate of responders increasing with the dHER2 dose and the number and frequency of immunizations.

A phase I/II trial of the safety and clinical activity of a HER2-protein based immunotherapeutic for treating women with HER2-positive metastatic breast cancer.

The objectives of this phase I/II study (NCT00140738) were to evaluate the safety and clinical activity of a cancer immunotherapeutic agent (recombinant HER2 protein (dHER2) and the immunostimulant AS15) in patients with HER2-overexpressing metastatic breast cancer (MBC). Forty HER2-positive MBC patients received up to 18 doses (12q2w, 6q3w) of dHER2 immunotherapeutic, as first- or second-line therapy following response to trastuzumab-based treatment as maintenance. Toxicity was graded by the Common Terminology Criteria for Adverse Events (CTCAE) and clinical activity was evaluated by target lesion assessment according to the Response Evaluation Criteria in Solid Tumors (RECIST). Immunogenicity was assessed. The dHER2 immunotherapeutic was well tolerated: grade 1/2 adverse events (AEs) were most common. No cardiac events were observed and one patient experienced an asymptomatic decrease of left ventricular ejection fraction below the normal range (47 %). Both humoral and cellular immunogenicity to the dHER2 antigen was observed. No patient discontinued the immunizations because of AEs but 35/40 withdrew prematurely, 34 because of disease progression (24/34 before or at the tumor assessment after dose 6). One patient achieved a complete response lasting 11 months and one patient had a partial response lasting 3.5 months. Ten patients experienced stable disease ≥26 weeks with 4/10 still in stable disease at the last tumor assessment after 47 weeks. Immunization of MBC patients with the dHER2 immunotherapeutic was associated with minimal toxicity and no cardiac events. Clinical activity was observed with two objective responses and prolonged stable disease for 10/40 patients.

Safety and Immunogenicity of MAGE-A3 Cancer Immunotherapeutic with or without Adjuvant Chemotherapy in Patients with Resected Stage IB to III MAGE-A3-Positive Non-Small-Cell Lung Cancer.

INTRODUCTION: To assess the safety and immunogenicity of MAGE-A3 immunotherapeutic in patients with stage IB-III MAGE-A3-positive non-small-cell lung cancer (NSCLC) who were or were not undergoing standard cisplatin/vinorelbine chemotherapy. METHODS: This open, prospective, multicenter, parallel-group phase I study (NCT00455572) enrolled patients with resected (cohorts 1-3) or unresectable (cohort 4) MAGE-A3-positive NSCLC. MAGE-A3 immunotherapeutic (300 µg recombinant MAGE-A3 formulated with AS15) was administered (eight doses, 3 weeks apart) concurrent with (cohort 1), after (cohort 2), or without (cohort 3) standard-adjuvant chemotherapy, or after standard radiotherapy and/or chemotherapy (cohort 4). RESULTS: Sixty-seven patients received greater than or equal to 1 dose of MAGE-A3 immunotherapeutic. Grade 3/4 adverse events (AEs) were reported for 16 out of 19 (84%), 2 out of 18 (11%), 5 out of 18 (28%), and 1 out of 12 (8%) patients in cohorts 1, 2, 3, and 4, respectively. Many grade 3/4 AEs in cohort 1 (e.g., neutropenia) were typical of chemotherapy. Six patients, including three in cohort 1, reported study treatment-related grade 3/4 AEs (injection-site reactions or musculoskeletal/back pain, which resolved within 5 days). One patient (in cohort 4) died, but this and the other serious adverse events were not study treatment related. MAGE-A3-specific antibody responses to immunotherapy were induced in all patients evaluated in all cohorts. MAGE-A3-specific CD4 T-cell responses to immunotherapy were detected in 4 out of 11 (36%), 4 out of 15 (27%), 2 out of 8 (25%), and 5 out of 6 (83%) evaluated patients in cohorts 1, 2, 3, and 4, respectively; and CD8 T-cell responses were only detected in four patients. CONCLUSION: In resected and unresectable NSCLC patients and irrespective of whether standard chemotherapy was concurrent or not, MAGE-A3 immunotherapeutic is well tolerated and induces MAGE-A3-specific immune responses.

Predictive gene signature in MAGE-A3 antigen-specific cancer immunotherapy.

PURPOSE: To detect a pretreatment gene expression signature (GS) predictive of response to MAGE-A3 immunotherapeutic in patients with metastatic melanoma and to investigate its applicability in a different cancer setting (adjuvant therapy of resected early-stage non-small-cell lung cancer [NSCLC]). PATIENTS AND METHODS: Patients were participants in two phase II studies of the recombinant MAGE-A3 antigen combined with an immunostimulant (AS15 or AS02B). mRNA from melanoma biopsies was analyzed by microarray analysis and quantitative polymerase chain reaction. These results were used to identify and cross-validate the GS, which was then applied to the NSCLC data. RESULTS: In the patients with melanoma, 84 genes were identified whose expression was potentially associated with clinical benefit. This effect was strongest when the immunostimulant AS15 was included in the immunotherapy (hazard ratio [HR] for overall survival, 0.37; 95% CI, 0.13 to 1.05; P = .06) and was less strong with the other immunostimulant AS02B (HR, 0.84; 95% CI, 0.36 to 1.97; P = .70). The same GS was then used to predict the outcome for patients with resected NSCLC treated with MAGE-A3 plus AS02B; actively treated GS-positive patients showed a favorable disease-free interval compared with placebo-treated GS-positive patients (HR, 0.42; 95% CI, 0.17 to 1.03; P = .06), whereas among GS-negative patients, no such difference was found (HR, 1.17; 95% CI, 0.59 to 2.31; P = .65). The genes identified were mainly immune related, involving interferon gamma pathways and specific chemokines, suggesting that their pretreatment expression influences the tumor's immune microenvironment and the patient's clinical response. CONCLUSION: An 84-gene GS associated with clinical response for MAGE-A3 immunotherapeutic was identified in metastatic melanoma and confirmed in resected NSCLC.

Adjuvant MAGE-A3 immunotherapy in resected non-small-cell lung cancer: phase II randomized study results.

PURPOSE: The MAGE-A3 protein is expressed in approximately 35% of patients with resectable non-small-cell lung cancer (NSCLC). Several immunization approaches against the MAGE-A3 antigen have shown few, but often long-lasting, clinical responses in patients with metastatic melanoma. PATIENTS AND METHODS: A double-blind, randomized, placebo-controlled phase II study was performed assessing clinical activity, immunologic response, and safety following immunization with recombinant MAGE-A3 protein combined with an immunostimulant (13 doses over 27 months) in completely resected MAGE-A3-positive stage IB to II NSCLC. The primary end point was disease-free interval (DFI). RESULTS: Patients were randomly assigned to either MAGE-A3 immunotherapeutic (n = 122) or placebo (n = 60). After a median postresection period of 44 months, recurrence was observed in 35% of patients in the MAGE-A3 arm and 43% in the placebo arm. No statistically significant improvement in DFI (hazard ratio [HR], 0.75, 95% CI, 0.46 to 1.23; two-sided P = .254), disease-free survival (DFS; HR, 0.76; 95% CI, 0.48 to 1.21; P = .248), or overall survival (HR, 0.81; 95% CI, 0.47 to 1.40; P = .454) was observed. Corresponding analysis after a median of 70 months of follow-up revealed a similar trend for DFI and DFS. All patients receiving the active treatment showed a humoral immune response to the MAGE-A3 antigen, although no correlation was observed with outcome. No significant toxicity was observed. CONCLUSION: In this early development study with a limited number of patients, postoperative MAGE-A3 immunization proved to be feasible with minimal toxicity. These results are being investigated further in a large phase III study.

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.

Future perspectives in melanoma research. Meeting report from the "Melanoma Research: a bridge Naples-USA. Naples, December 6th-7th 2010".

Progress in understanding the molecular basis of melanoma has made possible the identification of molecular targets with important implications in clinical practice. In fact, new therapeutic approaches are emerging from basic science and it will be important to implement their rapid translation into clinical practice by active clinical investigation. The first meeting of Melanoma Research: a bridge Naples-USA, organized by Paolo A. Ascierto (INT, Naples, Italy) and Francesco Marincola (NIH, Bethesda, USA) took place in Naples, on 6-7 December 2010. This international congress gathered more than 30 international and Italian faculty members and was focused on recent advances in melanoma molecular biology, immunology and therapy, and created an interactive discussion across Institutions belonging to Government, Academy and Pharmaceutical Industry, in order to stimulate new approaches in basic, translational and clinical research. Four topics of discussion were identified: New pathways in Melanoma, Biomarkers, Clinical Trials and New Molecules and Strategies.

Phase I investigation of recombinant anti-human vascular endothelial growth factor antibody in patients with advanced cancer.

We assessed the tolerability, safety, pharmacokinetics and dose-limiting toxicity (DLT) of the recombinant humanized IgG4 anti-vascular endothelial growth factor (VEGF) monoclonal antibody, HuMV833, in patients with advanced cancer. Cohorts of patients with progressive solid tumours received escalating doses of HuMV833 as a 1-h intravenous (I.V.) infusion on days 1, 15, 22, and 29. Twenty patients (median Eastern Cooperative Oncology Group (ECOG) score 1) were accrued. HuMV833 infusions were well tolerated and there were no grade III or IV toxicities definitely related to the antibody. Grade I or II toxicities probably related to the antibody included fatigue, dyspnoea and rash. There were two episodes of asymptomatic hypocalcaemia, one at grade III and one grade IV, which were recorded in early follow-up. There were eight grade I episodes of asymptomatic elevation of activated partial thromboplastin time (APTT) and two grade III events; one in a patient receiving 1 mg/kg and the other receiving extended doses of 10 mg/kg. Pharmacokinetic analysis revealed a non-linear kinetic and an elimination half-life of between 8.2 (0.3 mg/kg) and 18.7 (10 mg/kg) days. One patient with ovarian cancer experienced a partial response (PR) of 9 months duration and eight had disease stabilisation (SD) including one patient with colorectal carcinoma whose disease was stable for 14 months. In 13 of the 14 samples taken from 12 patients, the plasma concentration of hepatocyte growth factor (HGF) was reduced 24 h after drug administration. HuMV833 is safe and lacked DLT at doses up to 10 mg/kg on this schedule. Multiple doses were well tolerated, despite occasional asymptomatic elevations in APTT. By combining pharmacokinetic, pharmacodynamic and toxicity data, we can identify doses of 1 and 3mg/kg for further investigation. HuMV833 appears to possess some clinical activity.

Molecular imaging and biological evaluation of HuMV833 anti-VEGF antibody: implications for trial design of antiangiogenic antibodies.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a potent angiogenic cytokine, and various inhibitory agents, including specific antibodies, have been developed to block VEGF-stimulated angiogenesis. We developed HuMV833, a humanized version of a mouse monoclonal anti-VEGF antibody (MV833) that has antitumor activity against a number of human tumor xenografts, and investigated the distribution and biologic effects of HuMV833 in patients in a phase I trial. METHODS: Twenty patients with progressive solid tumors were treated with various doses of HuMV833 (0.3, 1, 3, or 10 mg/kg). Positron emission tomography with (124)I-HuMV833 was used to measure the antibody distribution in and clearance from tissues. Magnetic resonance imaging was used to measure the vascular permeability surface area product with a first-pass pharmacokinetic model (k(fp)) to determine tumor vascular permeability. RESULTS: The antibody was generally well tolerated, although the incremental dose, phase I study design, and pharmacodynamic endpoints could not identify the optimum biologically active dose. Antibody distribution and clearance were markedly heterogeneous between and within patients and between and within individual tumors. HuMV833 distribution to normal tissues also varied among patients, but the antibody was cleared from these tissues in a homogeneous fashion. Permeability was strongly heterogeneous between and within patients and between and within individual tumors. All tumors showed a reduction in k(fp) 48 hours after the first treatment (median = 44%; range = 4%-91%). CONCLUSIONS: Because of the heterogeneity in tumor biology with respect to antibody uptake and clearance, we suggest that either intrapatient dose escalation approaches or larger, more precisely defined patient cohorts would be preferable to conventional strategies in the design of phase I studies with antiangiogenic compounds like HuMV833.