Randomized Phase II Trial Comparing Bevacizumab Plus Carboplatin and Paclitaxel With Carboplatin and Paclitaxel Alone in Previously Untreated Locally Advanced or Metastatic Non-Small-Cell Lung Cancer

PURPOSE

To investigate the efficacy and safety of bevacizumab plus carboplatin and paclitaxel in patients with advanced or recurrent non-small-cell lung cancer.

PATIENTS AND METHODS

In a phase II trial, 99 patients were randomly assigned to bevacizumab 7.5 (n = 32) or 15 mg/kg (n = 35) plus carboplatin (area under the curve = 6) and paclitaxel (200 mg/m²) every 3 weeks or carboplatin and paclitaxel alone (n = 32). Primary efficacy end points were time to disease progression and best confirmed response rate. On disease progression, patients in the control arm had the option to receive single-agent bevacizumab 15 mg/kg every 3 weeks.

RESULTS

Compared with the control arm, treatment with carboplatin and paclitaxel plus bevacizumab (15 mg/kg) resulted in a higher response rate (31.5% v 18.8%), longer median time to progression (7.4 v 4.2 months) and a modest increase in survival (17.7 v 14.9 months). Of the 19 control patients that crossed over to single-agent bevacizumab, five experienced stable disease, and 1-year survival was 47%. Bleeding was the most prominent adverse event and was manifested in two distinct clinical patterns; minor mucocutaneous hemorrhage and major hemoptysis. Major hemoptysis was associated with squamous cell histology, tumor necrosis and cavitation, and disease location close to major blood vessels.

CONCLUSION

Bevacizumab in combination with carboplatin and paclitaxel improved overall response and time to progression in patients with advanced or recurrent non-small-cell lung cancer. Patients with nonsquamous cell histology appear to be a subpopulation with improved outcome and acceptable safety risks.

Study to evaluate intraperitoneal (IP) ONCOS-102 with systemic durvalumab in patients with peritoneal disease who have epithelial ovarian (OC) or metastatic colorectal cancer (CRC): Phase 2 results

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Background: Locoregional treatment with oncolytic viruses may be used to improve the efficacy of immune checkpoint inhibitors at both treated and distant tumor sites. This study evaluated the combination of IP-administered ONCOS-102, an oncolytic adenovirus encoding for granulocyte macrophage colony stimulating factor (GM-CSF), with systemic durvalumab (durva) in patients (pts) with advanced OC or CRC who have failed prior chemotherapy. Methods: This open-label study (NCT02963831) evaluated ONCOS-102 (IP 3 x 1011 VP in 500ml saline [recommended phase 2 dose] weekly x 6) + durva (IV 1500 mg every 4 weeks x 12). One dose of cyclophosphamide was given prior to first ONCOS-102 dose. Phase 2 evaluated the activity of the combination using Simon’s 2-stage MINIMAX design. In MINIMAX stage 1, if ≥ 5 of 18 OC pts or ≥ 1 of 13 CRC pts met the efficacy criteria (progression free at end of week 24), 15 additional OC pts or 14 additional CRC pts were to be enrolled in stage 2. The efficacy endpoint would be met if ≥ 11 OC pts or ≥ 4 CRC pts remained progression free at 24 weeks. Safety, response rate and progression-free survival (PFS) by RECIST 1.1, overall survival (OS), and immunologic effects in tumors were evaluated. ITT population = all pts who received at least one dose of durva or ONCOS-102; per protocol (PP) population = all pts who received at least 60% of ONCOS-102 doses and at least 1 durva dose in the first 2 cycles. Results: In MINIMAX stage 1, the OC cohort did not meet the efficacy criteria and was closed. For CRC, stage 1 efficacy criteria were achieved and the cohort was opened for stage 2. As of the 14 Dec 2021 cutoff, CRC enrollment was complete, and all pts were followed for 24 weeks or until progression or off study. Two pts were progression free at 24 weeks (see table). Treatment-related adverse events (TRAEs) occurring in > 30% pts were vomiting, nausea, fatigue, chills, and pyrexia. There were no grade 4 or 5 TRAEs. Grade 3 TRAEs were reported in 8 pts, 2 in the OC cohort and 6 in CRC. All grade 3 TRAEs occurred in no more than 1 pt for each AE except abdominal pain, which occurred in 2 pts. Conclusions: The combination of IP ONCOS-102 and durva was well tolerated. The study did not meet its efficacy endpoint. Evaluation of pre- and on-therapy translational parameters is ongoing. Clinical trial information: NCT02963831. [Table: see text]

Exploring the safety, effect on the tumor microenvironment, and efficacy of itacitinib in combination with epacadostat or parsaclisib in advanced solid tumors: a phase I study

BACKGROUND

This phase I multicenter study was designed to evaluate the safety, tolerability, efficacy, and translational effects on the tumor microenvironment of itacitinib (Janus-associated kinase 1 (JAK1) inhibitor) in combination with epacadostat (indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor) or parsaclisib (phosphatidylinositol 3-kinase δ (PI3Kδ) inhibitor).

METHODS

Patients with advanced or metastatic solid tumors were enrolled and received itacitinib (100-400 mg once a day) plus epacadostat (50-300 mg two times per day; group A), or itacitinib (100-400 mg once a day) plus parsaclisib or parsaclisib monotherapy (0.3-10 mg once a day; group B).

RESULTS

A total of 142 patients were enrolled in the study. The maximum tolerated dose was not reached for either the combination of itacitinib plus epacadostat (n=47) or itacitinib plus parsaclisib (n=90). One dose-limiting toxicity of serious, grade 3 aseptic meningitis was reported in a patient receiving itacitinib 300 mg once a day plus parsaclisib 10 mg once a day, which resolved when the study drugs were withdrawn. The most common treatment-related adverse events among patients treated with itacitinib plus epacadostat included fatigue, nausea, pyrexia, and vomiting, and for patients treated with itacitinib plus parsaclisib were fatigue, pyrexia, and diarrhea. In the itacitinib plus epacadostat group, no patient had an objective response. Among patients receiving itacitinib 100 mg once a day plus parsaclisib 0.3 mg once a day, three achieved partial response for an objective response rate (95% CI) of 7.1% (1.50 to 19.48). Treatment with itacitinib plus epacadostat demonstrated some increase in tumor CD8⁺ T cell infiltration and minor changes in six plasma proteins, whereas treatment with itacitinib plus high-dose parsaclisib resulted in downregulation of 20 plasma proteins mostly involved in immune cell function, with no observed change in intratumoral CD8⁺ T cell infiltration.

CONCLUSION

Adverse events with JAK1 inhibition combined with either IDO1 or PI3Kδ inhibition were manageable, but the combinations demonstrated limited clinical activity or enhancement of immune activation in the tumor microenvironment.

TRIAL REGISTRATION NUMBER

NCT02559492.

Subclonal landscape of cancer drives resistance to immune therapy

Tumor mutation burden (TMB) is often used as a biomarker for immunogenicity and prerequisite for immune checkpoint inhibitor (ICI) therapy. However, it is becoming increasingly evident that not all tumors with high TMB respond to ICIs as expected. It has been shown that the ability of T-cells to infiltrate the tumor microenvironment and elicit a specific immune response is dependent not only on the TMB, but also on intra-tumor heterogeneity and the fraction of low-frequency subclonal mutations that make up the tumor. High intra-tumor heterogeneity leads to inefficient recognition of tumor neoantigens by T-cells due to their diluted frequency and spatial heterogeneity. Clinical studies have shown that tumors with a high degree of intra-tumor heterogeneity respond poorly to ICI therapy, and previous cytotoxic treatment may increase the intra-tumor heterogeneity and render second-line ICI therapy less effective. This paper reviews the role of ICI therapy when following chemotherapy or radiation to determine if they may be better suited as first-line therapy in patients with high TMB, low intra-tumor heterogeneity, and high PD-1, PD-L1, or CTLA-4 expression.

Tumor suppressor immune gene therapy to reverse immunotherapy resistance

BACKGROUND

While immune checkpoint inhibitors are becoming a standard of care for multiple types of cancer, the majority of patients do not respond to this form of immunotherapy. New approaches are required to overcome resistance to immunotherapies.

METHODS

We investigated the effects of adenoviral p53 (Ad-p53) gene therapy in combination with immune checkpoint inhibitors and selective IL2 or IL15 CD122/132 agonists in the aggressive B16F10 tumor model resistant to immunotherapies. To assess potential mechanisms of action, pre- and post- Ad-p53 treatment biopsies were evaluated for changes in gene-expression profiles by Nanostring IO 360 assays.

RESULTS

The substantial synergy of "triplet" Ad-p53 + CD122/132 + anti-PD-1 therapy resulted in potential curative effects associated with the complete tumor remissions of both the primary and contralateral tumors. Interestingly, contralateral tumors, which were not injected with Ad-p53 showed robust abscopal effects resulting in statistically significant decreases in tumor size and increased survival (p < 0.001). None of the monotherapies or doublet treatments induced the complete tumor regressions. Ad-p53 treatment increased interferon, CD8⁺ T cell, immuno-proteosome antigen presentation, and tumor inflammation gene signatures. Ad-p53 treatment also decreased immune-suppressive TGF-beta, beta-catenin, macrophage, and endothelium gene signatures, which may contribute to enhanced immune checkpoint inhibitor (CPI) efficacy. Unexpectedly, a number of previously unidentified, strongly p53 downregulated genes associated with stromal pathways and IL10 expression identified novel anticancer therapeutic applications.

CONCLUSIONS

These results imply the ability of Ad-p53 to induce efficacious local and systemic antitumor immune responses with the potential to reverse resistance to immune checkpoint inhibitor therapy when combined with CD122/132 agonists and immune checkpoint blockade. Our findings further imply that Ad-p53 has multiple complementary immune mechanisms of action, which support future clinical evaluation of triplet Ad-p53, CD122/132 agonist, and immune checkpoint inhibitor combination treatment.

Maintenance vigil immunotherapy in newly diagnosed advanced ovarian cancer: Efficacy assessment of homologous recombination proficient (HRP) patients in the phase IIb VITAL trial

5502

Background: In the VITAL (NCT02346747) trial, maintenance therapy with Vigil, an autologous tumor cell vaccine transfected with a DNA plasmid encoding GMCSF and bi-shRNA-furin for TGFβ expression control, following frontline platinum-based chemotherapy led to a recurrence-free survival (RFS) benefit in patients with advanced high-grade ovarian cancer (HR=0.69, 90% CI 0.44–1.07, p=0.078) and significantly in BRCA-wt patients (HR=0.51, 90% CI 0.30-0.88, p=0.020) ( Rocconi et al. Lancet Oncol. 2020). Here we report post-hoc HR deficiency (HRD) subgroup analysis and identification of an additional molecular subgroup sensitive to Vigil therapy involving STRING analysis. Methods: This double-blind, placebo-controlled, Phase 2b study randomized 92 patients with newly diagnosed stage III/IV ovarian cancer with a complete clinical response (CR) to frontline surgery and chemotherapy. Patients received 1 x 10e7 cells/ml of Vigil or placebo intradermally once a month for up to 12 doses or disease progression. RFS was the primary endpoint assessed by blinded independent central review. HRD status was determined according to the Myriad Genetics myChoice CDx assay (HRD score < 42 for proficient). Using tumor annotated DNA polymorphism data, a protein-protein interaction network was constructed using the STRING database. Properties of this network including topological distance and the identification of hub genes were used to predict a target molecular population sensitive to Vigil. Results: In the per-protocol population (PP, n=91), 62 BRCA-wt patients were tested for HRD status. Forty-five patients were HR proficient (HRP) and 17 patients were HR deficient (HRD). No HRP patients in the Vigil group reported treatment related Grade 3 or higher adverse events. From the time of study randomization median RFS was improved with Vigil (n=25) in HRP patients compared to placebo (n=20) (Table 1). Similarly, overall survival (OS) benefit was observed in the Vigil group compared to placebo (Table 1). Improved RFS was demonstrated for a subset of patients with STRING predicted molecular profile. Conclusions: Vigil immunotherapy as frontline maintenance in Stage III/IV ovarian cancer is well tolerated and showed clinical benefit in both BRCA-wt and HRP molecular profile patients. Results suggest a unique molecular network that enhances sensitivity to Vigil therapy. Clinical trial information: NCT02346747. [Table: see text]

Analysis of Adenoviral p53 Gene Therapy Clinical Trials in Recurrent Head and Neck Squamous Cell Carcinoma

Background

We conducted an analysis of previous adenoviral p53 (Ad-p53) treatment data in recurrent head and neck squamous cell carcinoma (HNSCC) patients to identify optimal Ad-p53 treatment methods for future clinical trials.

Methods

The analysis involved recurrent HNSCC patients treated with Ad-p53 for whom p53 genotyping and immunohistochemistry tumor biomarker studies had been performed (n = 70). Ad-p53 tumor treatment responses defined by RECIST 1.1 criteria were correlated with Ad-p53 dose and tumor p53 biomarkers. Gene expression profiles induced by Ad-p53 treatment were evaluated using the Nanostring IO 360 panel.

Results

Ad-p53 dose based upon the injected tumor volume had a critical effect on tumor responses. All responders had received Ad-p53 doses greater than 7 × 10¹⁰ viral particles/cm³ of tumor volume. There was a statistically significant difference in tumor responses between patients treated with greater than 7 × 10¹⁰ viral particles/cm³ compared to patients treated at lower Ad-p53 doses (Tumor Response 31% (9/29) for Ad-p53 > 7 × 10¹⁰ viral particles/cm³ versus 0% (0/25) for Ad-p53 < 7 × 10¹⁰ viral particles/cm³; p = 0.0023). All responders were found to have favorable p53 biomarker profiles defined by less than 20% p53 positive tumor cells by immunohistochemistry (IHC), wild type p53 gene sequence or p53 deletions, truncations, or frame-shift mutations without functional p53 tetramerization domains. Preliminary gene expression profiling results revealed that Ad-p53 treatment increased interferon signaling, decreased TGF-beta and beta-catenin signaling resulting in an increased CD8⁺ T cell signature which are associated with increased responses to immune checkpoint blockade.

Conclusions

Our findings have important implications for future p53 targeted cancer treatments and identify fundamental principles to guide Ad-p53 gene therapy. We discovered that previous Ad-p53 clinical trials were negatively impacted by the inclusion of patients with unfavorable p53 biomarker profiles and by under dosing of Ad-p53 treatment. Future Ad-p53 clinical trials should have favorable p53 biomarker profiles inclusion criteria and Ad-p53 dosing above 7 × 10¹⁰ viral particles/cm³ of injected tumor volume. Preliminary gene expression profiling identified p53 mechanisms of action associated with responses to immune checkpoint blockade supporting evaluation of Ad-p53 in combination with immune checkpoint inhibitors.

The abscopal effect of radiation therapy

Radiation therapy (RT) in some cases results in a systemic anticancer response known as the abscopal effect. Multiple hypotheses support the role of immune activation initiated by RT-induced DNA damage. Optimal radiation dose is necessary to promote the cGAS-STING pathway in response to radiation and initiate an IFN-1 signaling cascade that promotes the maturation and migration of dendritic cells to facilitate antigen presentation and stimulation of cytotoxic T cells. T cells then exert a targeted response throughout the body at areas not subjected to RT. These effects are further augmented through the use of immunotherapeutic drugs resulting in increased T-cell activity. Tumor-infiltrating lymphocyte presence and TREX1, KPNA2 and p53 signal expression are being explored as prognostic biomarkers.

A phase I combination study of vigil and atezolizumab in recurrent/refractory advanced-stage ovarian cancer: Efficacy assessment in BRCA1/2-wt patients

3002

Background: Recent studies have shown poor clinical outcomes and limited survival advantage to checkpoint inhibitors (CIs) in advanced stage ovarian cancer (OvC). Vigil is a personalized precision vaccine constructed from autologous tumor tissue transfected with a DNA plasmid encoding GM-CSF and bi-shRNA-furin thereby creating TGFβ expression control and enhancing immune activation. Phase 1 and 2 trials in OvC demonstrate safety, functional immune activation and clinical response benefit. Combining Vigil with CIs may broaden responsiveness of immunotherapy in OvC. Methods: This is a randomized, 3-part safety Phase 1 study of Vigil in combination with Atezolizumab in recurrent OvC patients. Part 2 is a randomized, intra-patient crossover study of Vigil first (VF) or Atezolizumab first (AF) for two cycles followed by sequence of the combination of the two agents. Vigil (1 x 106 or 1 x 107 cells/ml) or Atezolizumab (1200mg) were administered 1x every 21 days each cycle until progression or untoward adverse event. We now report the preliminary results of part 2 of the study. Results: Twenty-one patients were randomized (1:1) to VF (n = 11) or AF (n = 10), groups were similar in demographics. Grade 3/4 toxic events occurred in 17% of AF patients compared to 3% in VF patients. Median OS of VF patients (n = 11) was not reached vs. AF (n = 10) 10.8 months suggested modest advantage to VF (HR 0.33, one-sided p 0.097). However, the subset analysis of BRCA1/2 wild type (wt) demonstrated more significant overall survival benefit in VF (n = 7) median OS not reached vs. AF (n = 7) 5.2 months (HR 0.12, one-sided p 0.015). Conclusions: The combination of Vigil immunotherapy and checkpoint inhibitor atezolizumab in recurrent OvC demonstrated safety and suggest a lower toxicity profile and a significant OS advantage in recurrent BRCA1/2-wt OvC patients treated with Vigil first followed by the combination of Vigil and Atezolizumab. Clinical trial information: NCT03073525 . [Table: see text]

Phase I/II study to evaluate systemic durvalumab + intraperitoneal (IP) ONCOS-102 in patients with peritoneal disease who have epithelial ovarian (OC) or metastatic colorectal cancer (CRC): Interim phase I clinical and translational results

3017

Background: Metastasis to the peritoneal cavity is associated with end-stage disease in many cancers, including OC and CRC, both of which exhibit poor responses to checkpoint inhibitors. Locoregional treatment with oncolytic viruses may be used to improve the efficacy of checkpoint inhibitors at both treated and distant tumor sites. This study evaluates the combination of IP-administered ONCOS-102, an oncolytic adenovirus encoding for granulocyte macrophage colony stimulating factor (GMCSF), with systemic durvalumab, an anti PD-L1 antibody, in patients with peritoneal disease who have histologically confirmed OC or metastatic CRC and have failed prior standard therapies. Methods: This ongoing Phase 1/2, open-label study (NCT02963831) evaluates safety and antitumor/biologic activity of durvalumab (1500 mg IV, every 4 weeks x 12) + ONCOS-102 (IP, weekly x 6); cyclophosphamide is given pre first ONCOS-102 dose. Phase 1 uses a 3+3 design to evaluate the ONCOS-102 dose (1 or 3 x 1011 VP) to be given with durvalumab. Phase 2 evaluates the activity of the combination using Simon’s 2-stage MINIMAX design. Safety, response rate by RECIST 1.1, and immunological effects in tumors were evaluated for Phase 1; the current abstract reports on the phase 1 results. Results: Enrollment opened 7 Sep 2017; data cutoff, 1 Nov 2019. There were 17 patients treated in Phase 1: 8 CRC, 9 ovarian; 94% female; median age, 56 [37-77] years; ECOG PS0, 47%; ECOG PS1, 53%. There were no DLTs. Grade 3 treatment-related AEs included hypokalemia (n = 2); anemia, myocarditis, increased GGT, and influenza like illness (n = 1 each). There were 4 deaths due to PD. One patient had durable confirmed partial response and remains on treatment > 1 year; 4 patients had stable disease as best overall response. Two patients remained on treatment at data cutoff. Analysis of pre- and on-treatment tumor biopsies revealed changes in the tumor-infiltrating immune cells and PD-L1 expression, including an increase in tumor-infiltrating CD8 T cells in 5 of 11 evaluable patients. Conclusions: Combination of durvalumab and IP ONCOS-102 was safe, and no DLTs were observed. Preliminary analyses demonstrate evidence of biologic and clinical activity. Phase 2 enrollment is ongoing. Clinical trial information: NCT02963831 .

Safety and efficacy of pemigatinib plus pembrolizumab combination therapy in patients (pts) with advanced malignancies: Results from FIGHT-101, an open-label phase I/II study

3606

Background: Pemigatinib (INCB054828) is a selective fibroblast growth factor receptor (FGFR) 1–3 inhibitor with demonstrated efficacy as monotherapy in phase 1/2 (FIGHT-101) and phase 2 (FIGHT-201, -202, -203) trials in pts with advanced cancer. Here, we present preliminary safety, efficacy, and pharmacokinetic (PK) data for pemigatinib (PEMI) combined with pembrolizumab (PEMBRO), a programmed cell death protein-1 (PD-1) inhibitor, in pts with refractory advanced malignancies enrolled in the ongoing FIGHT-101 trial (NCT02393248). Methods: FIGHT-101 includes monotherapy (part 1 and 2) and combination therapy (part 3) cohorts. This analysis is based on pts enrolled in the PEMI + PEMBRO combination dose finding (3a) and dose expansion (3b) cohorts. Eligible adults had advanced malignancies who had progressed after prior therapy and for whom PEMBRO treatment was relevant; pts in part 3b had FGF/FGFR alterations. Pts received oral PEMI at 9 mg or 13.5 mg QD on an intermittent dosing (ID) schedule (21-day cycle, 14-day on/7-day off), or 13.5 mg QD on a continuous dosing (CD) schedule, plus PEMBRO 200 mg IV on day 1 of each 21-day cycle. Results: At data cutoff (August 30, 2019), 23 pts had received PEMI + PEMBRO; 22 (96%) had discontinued therapy (disease progression, 70%). Most frequent tumors were NSCLC (n = 3), bladder (n = 3), pancreatic, testicular, and sarcoma (each n = 2). Of 19 enrolled pts with baseline FGF/FGFR data; 5 had FGFR mutations or rearrangements. No dose-limiting toxicities occurred with PEMI + PEMBRO. The recommended PEMI dose combined with PEMBRO was 13.5 mg QD. Most frequent all-cause, all-grade (Gr) adverse events for ID (n = 17) were hyperphosphatemia (n = 14 [82%]; Gr ≥3, n = 0), anemia (n = 9 [53%]; Gr ≥3, n = 3 [18%]), and decreased appetite (n = 9 [53%]; Gr ≥3, n = 0); for CD (n = 6), hyperphosphatemia (n = 5 [83%]; Gr ≥3, n = 0), and dry mouth (n = 4 [67%]; Gr ≥3, n = 0). One pt discontinued, 2 reduced dose, and 13 interrupted dose due to AEs (none for hyperphosphatemia; dose interruption mainly for gastrointestinal AEs [n = 5]). One fatal AE occurred (suicide, not treatment-related). PK parameters for PEMI in the PEMI + PEMBRO combination were comparable with those for PEMI monotherapy. Five pts had partial response (3 had FGFR rearrangements or mutations); 5 pts had stable disease. Conclusions: PEMI + PEMBRO combination therapy was tolerable with no new safety signals, and demonstrated preliminary antitumor activity in pts with advanced malignancies including those with FGF/FGFR alterations. Clinical trial information: NCT02393248 .

Randomized phase II study of nivolumab (N) alone versus with pegilodecakin (PEG) in combination with N in patients (pts) with post-platinum immunotherapy-naive stage IV non-small cell lung cancer (NSCLC) and no or low PD-L1 expression (CYPRESS 2)

e21744

Background: Nivolumab (N) is an immune checkpoint inhibitor (CPI) approved to treat post-platinum NSCLC as monotherapy. PEG in combination with N has demonstrated promising efficacy in NSCLC pts in a phase I trial (IVY; NCT02009449; Naing et al., 2019 Lancet Oncol), providing rationale for this randomized phase II trial (CYPRESS 2). Methods: CYPRESS 2 was an open label phase II trial, for ECOG 0-1, PD-L1 negative or low (TPS 0-49%), Stage IV NSCLC pts, without known EGFR/ALK mutations. Pts were randomized 1:1 to arm N (240 mg every 14-days or 480 mg every 28-days as decided by investigator) v. arm PEG+N (received N as above + PEG daily of 0.8 mg if weight ≤80kg and 1.6mg if weight > 80 kg). Pts were stratified by tumor histology and smoking history and must have no prior history of cancer or CPI therapy. Primary endpoint was ORR (per RECIST v 1.1 per investigator). Secondary endpoints included PFS, OS, and safety. Exploratory endpoints included immune activation biomarkers (baseline and change from baseline), assessed by immunoassay. Results: As of Aug 28, 2019, 52 pts were randomized to PEG+N (n=27) or N (n=25). Median follow-up time was 11.6 months. The following results were found for PEG+N versus N: ORR 14.8% v. 12.0%, mPFS 1.9 v. 1.9 months with HR = 1.01 (95% CI [0.52, 1.95]), mOS 6.7 v. 10.7 months with HR = 1.87 (95% CI [0.77, 4.53]). Gr ≥3 treatment related adverse events (TRAEs) for PEG+N versus N were 70.4% vs. 16.7%. Gr 3 TRAEs of ≥10% incidence included anemia (40.7% v. 0%), fatigue (18.5% v. 0%), and thrombocytopenia (14.8% v. 0%). In PEG+N arm, increased circulating IL-18, Granzyme B, FasL, and IFNg levels and decreased TGFb levels were observed on treatment. Conclusions: Exploratory pharmacodynamic results were consistent with immunostimulatory signals of the IL-10R pathway. Despite evidence of biological effect, adding PEG to N did not lead to improvement in ORR, PFS, or OS in post-platinum advanced NSCLC with no or low PD-L1 expression. PEG+N arm demonstrated expected safety profile but overall higher toxicity compared to nivolumab alone. Clinical trial information: NCT03382912.

Randomized double-blind placebo-controlled trial of primary maintenance vigil immunotherapy (VITAL study) in stage III/IV ovarian cancer: Efficacy assessment in BRCA1/2-wt patients

6017

Background: Vigil is an autologous tumor cell vaccine constructed from autologous harvested tumor tissue transfected with a DNA plasmid encoding GMCSF and bi-shRNA-furin thereby creating TGFβ expression control. Methods: A randomized double-blind placebo-controlled trial of Vigil vs. placebo was performed in advanced stage frontline OC patients. Relapse-free survival (RFS) and safety were endpoints. Patients who achieved complete clinical response were randomized [1:1 to placebo (control group, CG) or Vigil (Vigil group, VG)] after completion of frontline surgery and chemotherapy. All patients received 1 x 10e7 cells/ml of Vigil or placebo intradermally once a month for up to 12 doses. Results: Ninety-two patients were randomized with 91 patients in the per-protocol population (PP), (VG n=46; CG n=45). 62 patients were tested for BRCA1/2 status. VG showed no added overall toxicity compared to CG and no grade 4/5 toxicities were observed. Grade 2/3 toxic events were observed in 18% of CG patients (most common bone pain, fatigue) compared to 8% of VG patients (most common nausea, musculoskeletal pain). From time of randomization median RFS for all 91 patients was favorable in the VG (HR 0.69, one-sided p 0.088).Stratified by BRCA status, an advantage in RFS was seen in the BRCA1/2-wt patients in VG (19.4 mo) compared to CG (8 mo) (HR 0.51, 90% CI 0.26 – 1.01, one-sided p 0.050) from time of randomization and HR of 0.49 (90% CI 0.25 – 0.97, one-sided p 0.038) from time of surgery. Median time from surgery to randomization was 208.5 days (6.9 mo) in VG vs. 200 days (6.6 mo) in CG. 37.5% BRCA1/2-wt Vigil treated patients relapsed compared to 71% of placebo at time of data snap for analysis (HR 0.51, one-sided p 0.05), (median follow-up of 34.3 mo for all n=91 subjects). Germline and somatic BRCA1/2 molecular testing via central third party is underway on all 91 patients under continued blinded conditions to validate activity in BRCA1/2-wt. Conclusions: Vigil immunotherapy as frontline maintenance in Stage III/IV ovarian cancer is well tolerated and showed RFS clinical benefit, particularly in BRCA1/2-wt disease. Clinical trial information: NCT02346747. [Table: see text]

First-in-Human, Multicenter, Phase I Dose-Escalation and Expansion Study of Anti-Mesothelin Antibody-Drug Conjugate Anetumab Ravtansine in Advanced or Metastatic Solid Tumors

PURPOSE

This phase I study, which to our knowledge is the first-in-human study of this kind, investigates the safety, tolerability, pharmacokinetics, and clinical activity of anetumab ravtansine, an antibody–drug conjugate of anti-mesothelin antibody linked to maytansinoid DM4, in patients with advanced, metastatic, or recurrent solid tumors known to express the tumor-differentiation antigen mesothelin.

PATIENTS AND METHODS

This phase I, open-label, multicenter, dose-escalation and dose-expansion study of anetumab ravtansine enrolled 148 adult patients with multiple solid tumor types. Ten dose-escalation cohorts of patients with advanced or metastatic solid tumors (0.15-7.5 mg/kg) received anetumab ravtansine once every 3 weeks, and 6 expansion cohorts of patients with advanced, recurrent ovarian cancer or malignant mesothelioma received anetumab ravtansine at the maximum tolerated dose once every 3 weeks, 1.8 mg/kg once per week, and 2.2 mg/kg once per week.

RESULTS

Forty-five patients were enrolled across the 10 dose-escalation cohorts. The maximum tolerated dose of anetumab ravtansine was 6.5 mg/kg once every 3 weeks or 2.2 mg/kg once per week. Thirty-two patients were enrolled in the 6.5 mg/kg once-every-3-weeks, 35 in the 1.8 mg/kg once-per-week, and 36 in the 2.2 mg/kg once-per-week expansion cohorts. The most common drug-related adverse events were fatigue, nausea, diarrhea, anorexia, vomiting, peripheral sensory neuropathy, and keratitis/keratopathy. There were no drug-related deaths. Anetumab ravtansine pharmacokinetics were dose proportional; the average half-life was 5.5 days. Among 148 patients with mesothelioma or ovarian, pancreatic, non–small-cell lung, and breast cancers, 1 had a complete response, 11 had partial responses, and 66 had stable disease. High levels of tumor mesothelin expression were detected in patients with clinical activity.

CONCLUSION

Anetumab ravtansine exhibited a manageable safety and favorable pharmacokinetic profile with encouraging preliminary antitumor activity in heavily pretreated patients with mesothelin-expressing solid tumors. The results allowed for the determination of recommended doses, schedules, and patient populations for anetumab ravtansine in phase II studies.

Efficacy and Safety of Avelumab Treatment in Patients With Advanced Unresectable Mesothelioma: Phase 1b Results From the JAVELIN Solid Tumor Trial

Importance

Patients with malignant mesothelioma whose disease has progressed after platinum and pemetrexed treatment have limited options. Anti-programmed cell death 1 (PD-1) antibodies have antitumor activity in this disease, but little is known about the activity of anti-programmed cell death ligand 1 (PD-L1) antibodies in patients with mesothelioma.

Objective

To assess the efficacy and safety of avelumab in a cohort of patients with previously treated mesothelioma.

Design, Setting, and Participants

Phase 1b open-label study (JAVELIN Solid Tumor) in patients with unresectable mesothelioma that progressed after platinum and pemetrexed treatment, enrolled at 25 sites in 3 countries between September 9, 2014, and July 22, 2015.

Interventions

Participants received avelumab, 10 mg/kg, every 2 weeks until disease progression, unacceptable toxic effects, or withdrawal from the study.

Main Outcomes and Measures

Prespecified end points included confirmed best overall response based on Response Evaluation Criteria In Solid Tumors, version 1.1; duration of response; progression-free survival (PFS); overall survival (OS); PD-L1 expression-based analyses; and safety.

Results

Of 53 patients treated with avelumab, the median age was 67 (range, 32-84) years; 32 (60%) were male. As of December 31, 2016, median follow-up was 24.8 (range, 16.8-27.8) months. Twenty patients (38%) had 3 or more previous lines of therapy (median, 2; range, 1-8). The confirmed objective response rate (ORR) was 9% (5 patients; 95% CI, 3.1%-20.7%), with complete response in 1 patient and partial response in 4 patients. Responses were durable (median, 15.2 months; 95% CI, 11.1 to not estimable months) and occurred in patients with PD-L1-positive tumors (3 of 16; ORR, 19%; 95% CI, 4.0%-45.6%) and PD-L1-negative tumors (2 of 27; ORR, 7%; 95% CI, 0.9%-24.3%) based on a 5% or greater PD-L1 cutoff. Disease control rate was 58% (31 patients). Median PFS was 4.1 (95% CI, 1.4-6.2) months, and the 12-month PFS rate was 17.4% (95% CI, 7.7%-30.4%). Median OS was 10.7 (95% CI, 6.4-20.2) months, and the median 12-month OS rate was 43.8% (95% CI, 29.8%-57.0%). Five patients (9%) had a grade 3 or 4 treatment-related adverse event, and 3 (6%) had a grade 3 or 4 immune-related, treatment-related adverse event. There were no treatment-related deaths.

Conclusions and Relevance

Avelumab showed durable antitumor activity and disease control with an acceptable safety profile in a heavily pretreated cohort of patients with mesothelioma.

Trial Registration

ClinicalTrials.gov identifier: NCT01772004.

A phase II, multicenter, single-arm trial of CV301 plus atezolizumab (Atezo) in locally advanced (unresectable) or metastatic urothelial cancer (UC)

TPS494

Background: Anti-PD1/PD-L1 can achieve durable responses in advanced UC but most patients (pts) do not respond. Combination strategies with agents that “prime” the immune system may improve outcomes. CV301 comprises two recombinant poxviruses, Modified Vaccinia Ankara (MVA) and Fowlpox (FPV), encoding the human transgenes for CEA, MUC-1, and a Triad of Co-stimulatory Molecules (TRICOM: ICAM-1, LFA-3, and B7-1). MVA-CV301 is used for priming doses and FPV-CV301 is used for booster doses to achieve a heterologous prime boost regimen. In preclinical studies, BN-platform vaccine plus PD1/PD-L1 inhibitors exhibited synergistic anti-tumor efficacy, T-cell infiltration, and PD-L1 upregulation in tumors. CEA and MUC-1 are expressed, in 41-90% and 55-91% of any stage UC, respectively, and in ~100% of metastatic UC. An ongoing Phase Ib trial of CV301 plus anti-PD-1 agent has demonstrated a similar safety profile to anti-PD-1 monotherapy with only mild vaccine-related adverse events (AEs). Methods: This is a Phase 2, single-arm, multi-institutional trial designed to study CV301 plus atezo as 1st-line treatment in pts with advanced UC ineligible for cisplatin-based chemotherapy regardless of PD-L1 (Cohort 1) and as salvage treatment in pts with UC progressing after platinum-based chemotherapy (Cohort 2). MVA-CV301 is given subcutaneously (SC) on Days 1 and 22 and FPV-CV301 SC every 21 days for 4 doses, then every 6 weeks until 6 months, then every 12 weeks until 2 years. Atezo 1200mg is given every 21 days. Primary endpoint is objective response rate (ORR; RECIST 1.1). Secondary endpoints: immune response, OS, PFS, response duration, AEs. Tumor and serial blood samples will be collected for biomarker analyses; 1-sided α is 0.025/cohort in this design. With a 2-stage design, success criteria are based on historic ORR (H0) and alternative ORR (H1) with ≥70% power. For Cohort 1, assuming H0 = 0.23, H1 = 0.43, then Cohort 1 sample size N1= 14, responders required at stage 1 to continue R1≥3, total accrual goal N = 33, total responders to reject H0, R≥13. For Cohort 2, assuming H0 = 0.15, H1 = 0.33, then N1= 13, R1≥2, N = 35, R≥10. Accrual has begun; completion is expected within 1 year. Clinical trial information: NCT03628716.

Safety and clinical activity of durvalumab monotherapy in patients with microsatellite instability–high (MSI-H) tumors

670

Background: MSI-H tumors have shown to be responsive to PD-1 inhibitor therapy. We evaluated the anti-PD-L1 mAb durvalumab in patients with MSI-H tumors, in two ongoing studies: a phase 1/2, multicenter, open-label study in patients with advanced solid tumors, and a phase 2 single-center study in patients with advanced colorectal cancer (CRC). Methods: Patients with MSI-H tumors (determined locally by immunohistochemistry or sequencing) received durvalumab 10 mg/kg IV every 2 weeks for 12 months or until confirmed progressive disease, whichever was first. Objectives were to evaluate safety and antitumor activity (per investigator-assessed RECIST v1.1). Results: As of Oct 16, 2017, 62 MSI-H patients (97% with prior anti-cancer therapy) received treatment in the multicenter study; median duration of follow-up was 29 months. Treatment-related adverse events (TRAEs) occurred in 37 patients (60%), most commonly diarrhea (15%), asthenia (11%), fatigue (11%), nausea (10%), and hypothyroidism (10%). Grade 3/4 TRAEs occurred in 2 patients (3%). There were no deaths or treatment discontinuations due to TRAEs. Objective response rates (ORR) were 23% for the total population and 22% for patients with CRC; 9 of 14 responders were ongoing at data cutoff. As of Sep 13, 2018, 11 patients with MSI-H CRC were treated in the single-center study; median duration of follow-up was 30 months. One patient discontinued treatment due to treatment-related aseptic meningitis (resolved with steroids); response rate and survival were similar to the multicenter study (Table). Conclusions: Durvalumab had a tolerable safety profile, and showed promising antitumor activity and overall survival in patients with MSI-H tumors. Clinical trial information: NCT01693562 and NCT02227667. [Table: see text]

Avelumab in patients with previously treated metastatic melanoma: phase 1b results from the JAVELIN Solid Tumor trial

Background

We report phase 1b data from patients enrolled in the JAVELIN Solid Tumor clinical trial (NCT01772004) with unresectable stage IIIC or IV melanoma that had progressed after ≥1 line of therapy for metastatic disease.

Patients and methods

Patients received avelumab (10 mg/kg)—a human anti–PD-L1 antibody. Assessments included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety.

Results

As of December 31, 2016, 51 patients were treated and followed for a median of 24.2 months (range, 16.1–31.5). Most patients had cutaneous (n = 28 [54.9%]) or ocular (n = 16 [31.4%]) melanoma and had received a median of 2 prior lines of therapy (range, 0–4), including ipilimumab (n = 26 [51.0%]). The confirmed ORR was 21.6% (95% CI, 11.3–35.3; complete response, 7.8%; partial response, 13.7%). The median duration of response was not estimable (95% CI, 2.6 months-not estimable). Median PFS and OS were 3.1 months (95% CI, 1.4–6.3) and 17.2 months (95% CI, 6.6-not estimable), respectively. Subgroup analyses suggested meaningful clinical activity (ORR [95% CI]) in patients with non-ocular melanoma (31.4% [16.9–49.3]), PD-L1–positive tumors (42.1% [20.3–66.5]), or prior ipilimumab therapy (30.8% [14.3–51.8]). Thirty-nine patients (76.5%) had a treatment-related adverse event (TRAE), most commonly infusion-related reaction (29.4%), fatigue (17.6%), and chills (11.8%); 4 patients (7.8%) had a grade 3 TRAE. Five patients (9.8%) had an immune-related TRAE (all were grade 1/2). No grade 4 TRAEs or treatment-related deaths were reported.

Conclusion

Avelumab showed durable responses, promising survival outcomes, and an acceptable safety profile in patients with previously treated metastatic melanoma.

Trial registration

ClinicalTrials.gov identifier: NCT01772004.

Electronic supplementary material

The online version of this article (10.1186/s40425-018-0459-y) contains supplementary material, which is available to authorized users.

Evofosfamide for the treatment of human papillomavirus-negative head and neck squamous cell carcinoma

Evofosfamide (TH-302) is a clinical-stage hypoxia-activated prodrug of a DNA-crosslinking nitrogen mustard that has potential utility for human papillomavirus (HPV) negative head and neck squamous cell carcinoma (HNSCC), in which tumor hypoxia limits treatment outcome. We report the preclinical efficacy, target engagement, preliminary predictive biomarkers and initial clinical activity of evofosfamide for HPV-negative HNSCC. Evofosfamide was assessed in 22 genomically characterized cell lines and 7 cell line-derived xenograft (CDX), patient-derived xenograft (PDX), orthotopic, and syngeneic tumor models. Biomarker analysis used RNA sequencing, whole-exome sequencing, and whole-genome CRISPR knockout screens. Five advanced/metastatic HNSCC patients received evofosfamide monotherapy (480 mg/m2 qw × 3 each month) in a phase 2 study. Evofosfamide was potent and highly selective for hypoxic HNSCC cells. Proliferative rate was a predominant evofosfamide sensitivity determinant and a proliferation metagene correlated with activity in CDX models. Evofosfamide showed efficacy as monotherapy and with radiotherapy in PDX models, augmented CTLA-4 blockade in syngeneic tumors, and reduced hypoxia in nodes disseminated from an orthotopic model. Of 5 advanced HNSCC patients treated with evofosfamide, 2 showed partial responses while 3 had stable disease. In conclusion, evofosfamide shows promising efficacy in aggressive HPV-negative HNSCC, with predictive biomarkers in development to support further clinical evaluation in this indication.

Avelumab in patients with previously treated mesothelioma: Updated phase 1b results from the JAVELIN Solid Tumor trial

166

Background: Avelumab, a human anti-PD-L1 IgG1 monoclonal antibody, is approved for treatment of metastatic Merkel cell carcinoma (US and EU) and advanced urothelial carcinoma progressed on platinum therapy (US). Here, we report updated phase 1b data for avelumab in patients (pts) with previously treated mesothelioma. Methods: Pts with unresectable pleural or peritoneal mesothelioma whose disease had progressed after platinum and pemetrexed therapy received avelumab 10 mg/kg IV Q2W until progression, unacceptable toxicity, or withdrawal. Tumors were assessed every 6 wks (RECIST 1.1). Endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs; NCI CTCAE v4.0). Results: As of Dec 31, 2016, 53 pts were treated and followed for a median of 24.8 mos (range 16.8–27.8). Median age was 67 y (range 32–84). Pts had received a median of 2 prior lines of therapy (range 1–8). Confirmed ORR was 9.4% (95% CI 3.1–20.7; complete response in 1.9%, partial response in 7.5%). In pts with 1 (n = 18), 2 (n = 15) or ≥3 (n = 20) prior lines of therapy, ORR was 5.6%, 13.3% and 10.0% respectively. Median duration of response was 15.2 mos (95% CI 11.1–not estimable). 26 pts (49.1%) had stable disease as best response and the disease control rate was 58.5%. Median PFS was 4.1 mos (95% CI 1.4–6.2) and the 6-mo PFS rate was 38.0% (95% CI 24.2–51.7). Median OS was 10.9 mos (95% CI 7.5–21.0) and the 12-mo OS rate was 45.9% (95% CI 31.9–58.8). In evaluable pts with PD-L1+ (n = 16) and PD-L1− (n = 27) tumors (≥5% tumor cell cutoff), ORR was 18.8% (95% CI 4.0–45.6) and 7.4% (95% CI 0.9–24.3), and the 6-mo PFS rate was 37.5% (95% CI 14.1–61.2) and 42.0% (95% CI 23.1–59.8). 43 pts (81.1%) had a treatment-related (TR)AE, most commonly ( > 10%) infusion-related reaction (35.8%; all grade 1/2), chills (15.1%), fatigue (15.1%) and pyrexia (11.3%). 5 pts (9.4%) had a grade ≥3 TRAE. 14 pts (26.4%) had an immune-related AE, which was grade ≥3 in 3 pts (5.7%; pneumonitis, colitis, and type 1 diabetes mellitus). No treatment-related deaths occurred. Conclusions: Avelumab showed clinical activity and acceptable safety in pts with previously treated mesothelioma. Clinical trial information: NCT01772004.

Updated overall survival and safety profile of durvalumab monotherapy in advanced NSCLC

169

Background: Single-agent durvalumab is being evaluated in patients with advanced squamous and non-squamous NSCLC in an ongoing Phase 1/2 study (NCT01693562). Here we present updated survival and safety data in NSCLC patients. Methods: Treatment-naïve (1L) and previously treated (2L or 3L+) stage IIIB/IV NSCLC patients received durvalumab 10 mg/kg Q2W for up to 12 months. Patients were stratified by tumor PD-L1 expression (Ventana PD-L1 [SP263] Assay [PD-L1 high: ≥25% of tumor cells with membrane staining]), treatment line, and histology. Results: As of 05 September 2017, 304 NSCLC patients received durvalumab monotherapy. Median duration of follow-up was 35.6 (0.3–50.9) months. Investigator-assessed ORR ranged between 23.2% and 30.0% among PD-L1 high patients, and between 3.6% and 8.3% among PD-L1 low/negative patients. Median PFS and median OS were longer in PD-L1 high vs PD-L1 low/negative patients (Table). Any-grade treatment-related AEs (TRAEs) were reported in 57.2% of pts (including fatigue, 17.4%, decreased appetite, 9.2%, diarrhea, 8.9%); in 10.2% of pts these were Grade 3 or 4. TRAEs resulting in treatment discontinuation were reported in 17 patients (5.6%); 1 patient had a Grade 5 TRAE (pneumonia). Conclusions: In this ongoing phase 1 study, OS and safety profile appear encouraging in treatment-naïve and previously treated NSCLC patients, particularly among PD-L1 high patients. Further investigation regarding PD-L1 expression for selection of patients who most likely benefit from durvalumab is needed. Clinical trial information: NCT01693562. [Table: see text]

Avelumab in patients with previously treated metastatic melanoma: Phase 1b results from the JAVELIN Solid Tumor trial

191

Background: Avelumab is a human anti–PD-L1 IgG1 monoclonal antibody that is approved for the treatment of metastatic Merkel cell carcinoma (US and EU) and advanced urothelial carcinoma progressed on platinum therapy (US). Here, we report phase 1b data for avelumab in a cohort of patients (pts) with previously treated metastatic melanoma. Methods: Pts with unresectable stage IIIC or IV melanoma progressed after ≥1 line of therapy for metastatic disease received avelumab 10 mg/kg IV Q2W until progression, unacceptable toxicity, or withdrawal. Endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs; NCI CTCAE v4.0). Results: As of Dec 31, 2016, 51 pts were treated and followed for a median of 24.2 mo (range 16.1–31.5). Median age was 64 y (range 31–84). Site of primary tumor was cutaneous (n = 28, 54.9%), ocular (n = 16, 31.4%), mucosal (n = 2, 3.9%), or unknown (n = 5, 9.8%). Pts had received a median of 2 prior lines of therapy for advanced disease (range 0–4), including ipilimumab (n = 26, 51.0%). Confirmed ORR was 21.6% (95% CI 11.3–35.3), with complete response in 7.8% and partial response in 13.7%. In pts with cutaneous melanoma, ORR was 28.6% (95% CI 13.2–48.7). There were no objective responses in pts with ocular melanoma; however, 7 pts (43.8%) had stable disease. In pts with ≤1 (n = 25), 2 (n = 17), or ≥3 (n = 9) prior lines, ORR was 36.0% (95% CI 18.0–57.5), 11.8% (95% CI 1.5–36.4), and 0% (95% CI 0–33.6), respectively. Antitumor activity by PD-L1 status will be presented. Median duration of response was not estimable (NE) (95% CI 2.6 mo–NE). Median PFS was 3.1 mo (95% CI 1.4–6.3) and the 6-mo PFS rate was 39.2% (95% CI 25.2–52.9). Median OS was 18.5 mo (95% CI 9.3–NE) and the 12-mo OS rate was 62.3% (95% CI 46.9–74.4). 39 pts (76.5%) had a treatment-related (TR)AE, most commonly infusion-related reaction (25.5%), fatigue (17.6%), and chills (11.8%). 4 pts (7.8%) had a grade ≥3 TRAE. 5 pts (9.8%) had an immune-related AE; all were grade 1/2. No treatment-related deaths occurred. Conclusions: Avelumab showed durable responses, promising survival outcomes, and an acceptable safety profile in pts with previously treated metastatic melanoma. Clinical trial information: NCT01772004.

Safety and Activity of Varlilumab, a Novel and First-in-Class Agonist Anti-CD27 Antibody, in Patients With Advanced Solid Tumors

Purpose

CD27, a costimulatory molecule on T cells, induces intracellular signals that mediate cellular activation, proliferation, effector function, and cell survival upon binding to its ligand, CD70. Varlilumab is a novel, first-in-class, agonist CD27 antibody that stimulates the CD27 pathway, which results in T-cell activation and antitumor activity in tumor models. This first-in-human, dose-escalation and expansion study evaluated the safety, pharmacology, and activity of varlilumab in patients with advanced solid tumors.

Methods

In a 3 + 3 dose-escalation design (n = 25), patients received a single dose of varlilumab (0.1, 0.3, 1.0, 3.0, or 10 mg/kg intravenously) with a 28-day observation, followed by up to five multidose cycles (one dose per week for 4 weeks), depending on tumor response. Expansion cohorts were initiated at 3.0 mg/kg in patients with melanoma (n = 16) and renal cell carcinoma (RCC; n = 15). Primary objectives were to assess the safety and the maximum tolerated and optimal biologic doses of varlilumab. Secondary objectives were to evaluate the pharmacokinetics, pharmacodynamics, and clinical antitumor activity of varlilumab.

Results

Exposure to varlilumab was linear and dose proportional across dose groups. Only one patient experienced a dose-limiting toxicity—grade 3 transient asymptomatic hyponatremia at the 1.0-mg/kg dose level. Treatment-related adverse events were generally grade 1 or 2 in severity. Evidence of biologic activity consistent with CD27 stimulation—chemokine induction, T-cell stimulation, regulatory T cell depletion—was observed at all dose levels. A patient with metastatic RCC experienced a partial response (78% shrinkage, progression-free survival > 2.3 years). Eight patients experienced stable disease > 3 months, including a patient with metastatic RCC with progression-free survival of > 3.9 years.

Conclusion

Dose escalation of varlilumab to 10 mg/kg was well tolerated without identification of a maximum tolerated dose. Varlilumab was biologically and clinically active.

Long-term followup of bi-shRNAfurin and GMCSF augmented autologous tumor cell immunotherapy treated colorectal cancer patients in phase I and IIa studies

e15100

Background: Vigil is an immuno-stimulatory autologous tumor cell therapy, which uses patient tumor cells transfected with a plasmid encoding genes to upregulate GM-CSF and down regulate TGFβ 1&2. It is administered monthly by intra-dermal injection. In Phase I and IIa trials patients with over 19 different tumor types were safely treated. Rapid and durable systemic immune activation was demonstrated using an IFNγ ELISPOT assay. Methods: Data are summarized for a group of 9 patients with advanced colorectal cancer followed for up to 3.5 years. Results: Six women and 3 men with Stage III or IV colorectal cancer were treated between March, 2010 and September, 2013. Six patients received Vigil as a monotherapy and 3 in combination with FOLFOX chemotherapy. Results: Demographics and treatment details are displayed below. Two patients with Stage III disease received combination therapy after complete surgical resection, and remain disease free over 3 years from surgery. The patients received 9 and 12 Vigil injections with a brisk and durable ELISPOT reactions. Conclusions: Preliminary results suggest that Vigil can be combined safely with FOLOX chemotherapy and still elicit a systemic immune response. Long term disease free survival has been observed in several patients justifying further exploration of this combination. More detailed molecular characterization and neoantigen identification of patient tumor will be undertaken in future studies. A combination with immune checkpoint inhibitors may also be explored. [Table: see text]

A phase 1b study to evaluate TAK-659 in combination with nivolumab in patients (pts) with advanced solid tumors

TPS3104

Background: TAK-659 is an investigational, reversible, potent dual inhibitor of SYK and FLT-3. In ongoing early-phase studies (NCT02000934; NCT02323113), TAK-659 demonstrated an acceptable pharmacokinetic and safety profile, with evidence of preliminary activity in pts with DLBCL, follicular lymphoma, CLL, and AML (Kaplan et al. Blood 2016;128:624/2834). In preclinical studies, TAK-659 in combination with nivolumab, an anti-PD-1 checkpoint inhibitor, resulted in loss of myeloid suppressor cells (MDSCs), increased T-cell activation, and complete tumor growth suppression (Kannan et al. Eur J Cancer 2016;69:S92). This first-in-human combination study will investigate the efficacy and safety of TAK-659 and nivolumab in pts with advanced solid tumors. Methods: This open-label, multicenter, phase 1b study (NCT02834247) will include dose-escalation and expansion phases. Pts with advanced solid tumors who have failed ≥1 prior lines of therapy and have no effective therapeutic options available by investigator assessment will be eligible for the dose-escalation phase. Pts will receive oral TAK-659 at doses of 60–100 mg QD in a standard 3+3 schema, plus nivolumab 3 mg IV on days 1 and 15 of 28-day cycles. The expansion phase at the recommended phase 2 dose (RP2D) will include 3 cohorts of pts with relapsed/refractory metastatic triple-negative breast cancer, locally advanced/metastatic NSCLC, or locally advanced/metastatic head and neck squamous cell carcinoma (n = 30 response-evaluable pts in each cohort; 24 naïve, 6 relapsed/refractory to prior anti-PD-1/PD-L1 therapy). Ten pts in each cohort will receive 2 weeks of single-agent TAK-659 before starting combination therapy; the other 20 pts will receive combination therapy throughout. The primary endpoints are maximum tolerated dose/RP2D (dose-escalation phase) and overall response rate by investigator per RECIST v1.1 (expansion phase). Secondary endpoints include adverse events, disease control rate, duration of response, progression-free survival, overall survival, and TAK-659 pharmacokinetics. There are currently 7 pts enrolled; recruitment to the 100 mg dose-escalation cohort is ongoing. Clinical trial information: NCT02834247.

A bi-shRNAfurin and GMCSF engineered autologous tumor cell immunotherapy vs. gemcitabine + docetaxel for Ewing sarcoma and with cryoablation in Ewing family tumors

TPS11079

Background: Vigil, an immuno-stimulatory autologous cellular therapy, uses patient tumor cells transfected with a plasmid encoding genes for GM-CSF and furin (to down regulate TGFβ 1&2). A Phase I study in relapsed Ewing’s sarcoma. (N = 16) had one 9 month partial response and a two-year survival rate of 44% [1]. Rapid, durable systemic immune activation was seen in the majority of patients using an IFNƔ ELISPOT assay [2]. We seek to extend these early findings in a randomized Phase 2 study (NCT02511132). Methods: Following surgery (for Vigil manufacture), patients are randomized 1:1 to Vigil (1 x 107cells/ml by monthly intradermal injection), or to chemotherapy with gemcitabine 675mg/m2 IV D1 and D8 and docetaxel 75 mg/m2 IV D8 every 21 days. Key eligibility criteria include: Age > 2, histologically documented metastatic Ewing's, refractory or intolerant to ≥2 prior lines of chemotherapy, and availability of at least 4 doses of manufactured Vigil. Patients with bone only disease are ineligible. The primary objective is to compare the overall survival of patients treated with Vigil vs. chemotherapy. The sample size of 62 patients assumes a one-year survival rate of 25% in the chemotherapy group vs. 60% in the Vigil group, corresponding to a hazard ratio of 0.383 favoring Vigil. Results: As of January 2017, thirteen patients have been randomized at 10 centers in the U.S. The design allows for reduction in disease burden prior to surgery using modalities like SBRT and interventional radiology. Toxicity of Vigil has been low compared to chemotherapy. Time to disease progression is being assessed in patients who crossover to Vigil after progressing on chemotherapy. Systemic control of metastatic lesions using cryoablation is also being assessed in other patients (e.g. DSRCT liver metastases) using a separate IND. Conclusions: Although associated with systemic immune activation, additional means to reduce disease burden such as SBRT and cryoablation can possibly improve patient health and augment Vigil efficacy. References: 1.Ghisoli M, Barve M, et al. Mol Ther. 2016 Apr 25 2. Oh J, Barve M, et al. Gynecologic Oncology 2016; 143: 504–510. Clinical trial information: NCT02511132.

Safety and clinical activity of durvalumab monotherapy in patients with hepatocellular carcinoma (HCC)

4071

Background: Durvalumab, an anti-PD-L1 mAb, has shown early and durable clinical activity with manageable safety in an ongoing Phase 1/2, multicenter, open-label study in pts with advanced solid tumors. Interim analyses from the HCC cohort in the dose-expansion part of this study are reported here. Methods: Patients with HCC (Child-Pugh class A) received durvalumab 10 mg/kg i.v. q2w for 12 months or until confirmed progressive disease, whichever occurred first. The primary objective was to evaluate the safety profile; secondary objective was to assess the antitumor activity (investigator-assessed RECIST v1.1). Clinical activity was evaluated for the total HCC population and by viral status. Results: As of Oct 24 2016, 40 HCC pts with median 23.9 (range 2.4–34.7) weeks follow-up received durvalumab. 93% had prior sorafenib. Treatment-related AEs occurred in 80.0% of pts, most commonly fatigue (27.5%), pruritus (25.0%) and elevated aspartate aminotransferase (AST) (22.5%). Grade 3–4 treatment-related AEs were reported in 20.0% of pts, most commonly elevated AST (7.5%) and elevated alanine aminotransferase (5.0%). 7 (17.5%) pts completed the initial 12-month treatment and 7 (17.5%) pts discontinued treatment because of an AE (none related to treatment). There were no deaths due to treatment-related AEs. Clinical activity is presented in the table. 4 pts achieved a PR; 2 were ongoing at data cut-off. Conclusions: Durvalumab had an acceptable safety profile and showed promising antitumor activity and OS in pts with HCC, particularly HCV+ pts. Clinical trial information: NCT01693562. [Table: see text]

PROCLAIM-001: A first-in-human trial to assess tolerability of the protease-activatable anti-PD-L1 Probody CX-072 in solid tumors and lymphomas

TPS3107

Background: CX-072 is a novel Probody™ therapeutic (PbTx) targeting PD-L1. PbTx’s are fully recombinant antibody prodrugs designed to be converted to active antibodies by tumor-associated proteases that are highly expressed malignant tissue; the PbTx remains largely inactive in normal tissues. In pre-clinical tumor models, a PD-L1-directed PbTx provided comparable anti-tumor efficacy to its parental anti-PD-L1 antibody, but displayed reduced auto-immunity in a model of Type 1 diabetes. Based on these pre-clinical data, CX-072 has the potential to enable combination therapies that are otherwise poorly tolerated. This Phase 1/2 study (PROCLAIM-001 (PRObody CLinical Assessment In Man) assesses the tolerability and antitumor activity of CX-072 in humans with an emphasis on immune-related adverse events, particularly in combinations. CX-072 will be administered as monotherapy (Part A), in combination with 2 schedules of ipilimumab (Parts B1 and B2) and in combination with vemurafenib (Part C). The expansion cohort (Part D) will include CX-072 monotherapy in PD-L1 responsive tumor types. Methods: Key eligibility criteria are as follows: Parts A and B1: checkpoint inhibitor-naive patients with advanced, refractory solid tumor or lymphoma (unmeasurable disease allowed) for whom approved PD agents are not available. Part B2: advanced, refractory solid tumors or lymphomas with measurable disease who have progressed on a previous treatment with a PD-(L)1 inhibitor, but did not discontinue due to toxicity. Part C: checkpoint inhibitor, BRAF-inhibitor and MEK-inhibitor-naïve metastatic V600E BRAF-mutated melanoma. Patients without an active autoimmune disease, ongoing infection, and ECOG PS 0-1 may be eligible to participate in the study. Dose escalation follows the 3+3 design in all arms. Ipilimumab (Parts B1 and B2) is dosed at the approved 3 mg/kg every 3 weeks x 4. The dose of vemurafenib (Part C) is 960 mg/kg twice daily. Exploratory biomarkers are used to characterize tumor protease activity, inflammatory changes within the tumor, and CX-072 activation in tumor versus peripheral blood. Clinical trial information: NCT03013491.

Phase 1b/2, open label, multicenter, study of intratumoral SD-101 in combination with pembrolizumab in anti-PD1 naïve & experienced metastatic melanoma patients

9550

Background: SD-101 is a synthetic CpG-ODN agonist of TLR 9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells to activate T cell anti-tumor responses. Pembro is a PD-1 inhibitor approved for the treatment of metastatic melanoma. This study, MEL-01 (NCT02521870), assesses the safety and preliminary efficacy of SD-101 in combination with pembro in stage IIIC-IV melanoma. Methods: A modified 3+3 design was used for SD-101 dose escalation of 1, 2, 4, and 8 mg injected in a single tumor lesion Q1W x 4 then Q3W x 7 in combination with pembro (200 mg IV Q3W). Tumor responses were assessed per investigator using RECIST v1.1. Results: In phase Ib, 22 pts were enrolled: median age 64 y/o, male 68%, white 82%, Stage IV/IIIc 86%/14%, LDH > 1 ULN 27%, ≥ 3 prior lines therapy 36%, anti-PD-1 naïve (n = 9) and experienced (n = 13). There has been no dose limiting toxicity (DLT) to date. The most common (≥20%) treatment-related AEs (TRAEs) were transient low-grade fatigue, myalgia, headache, chills and injection site reactions. Grade ≥ 3 TRAEs were observed in 59.1% pts (most common: myalgia 13.6% and injection site pain 13.6%). Immune-related AEs occurred in 2 pts. One had a G2 pneumonitis on Day 23 resulting in drug withdrawal and the other G3 hypophysitis (85 days after last treatment). No deaths occurred. Responses were observed at all doses in PD-1 inhibitor naïve pts, both at the injected and non-injected lesions. A response was seen at the 8 mg dose in PD-1 inhibitor experienced pts. With median f/u of 97 days (max 382), the ORR was 66.7% in the PD-1 inhibitor naïve patients with best overall response of CR 22.2% (n = 2), PR 44.4% (n = 4), SD 11.1% (n = 1), PD 11.1% (n = 1), and NE 11.1% (n = 1). In the PD-1 inhibitor experienced pts: PR 7.7% (n = 1) and SD 38.5% (n = 5). Conclusions: The combination of SD-101 and pembro was well tolerated and demonstrates no worsening of the expected toxicities of each of the individual monotherapies. These interim data support enhanced activity of adding SD-101 to pembro in anti-PD-1 naive metastatic melanoma as well as potential activity in anti-PD-1 experienced pts. Additional follow up data through May 15, 2017 will be presented. Clinical trial information: NCT02521870.

Phase 1 study to evaluate the safety and tolerability of MEDI4736 (durvalumab, DUR) + tremelimumab (TRE) in patients with advanced solid tumors

3069

Background: DUR is a human IgG1 monoclonal antibody (mAb) that blocks PD-L1. TRE is a human IgG2 mAb inhibitor of CTLA-4. Blocking these checkpoints can result in antitumor activity in some solid tumors. The targets for DUR and TRE are non-redundant, providing sound rationale for clinical testing of the combination. Methods: This is an ongoing Phase 1, multicenter, open label study (NCT01975831) with a dose escalation (3+3 design) and subsequent expansion phase. Patients (pts) with renal cell carcinoma (RCC), cervical (CC), colorectal (CRC), non-triple-negative breast (NTNBC), ovarian (OC), non-small cell lung, or head and neck cancer are eligible. Primary endpoints are safety/tolerability and identification of maximum tolerated dose (MTD) of the combination. Secondary objectives include tumor response and progression-free/overall survival. Results: As of 16 Dec 2016, 105 pts were treated. DUR 1500 mg every 4 weeks (Q4W) and TRE 75 mg Q4W X 4 was the regimen used for opening the expansion phase. Dose-limiting toxicities were reported in 4 pts: diarrhea, colitis, abnormal liver function tests (abn LFTs), and hyponatremia. The majority of treatment-related AEs (TRAEs) were Grades (Gr) 1 and 2. TRAEs ≥ Gr 3 were reported in 12 pts; the majority were diarrhea/colitis (n = 5) and abn LFTs (n = 4) and responded to established treatment algorithms. There was 1 Gr 5 TRAE: multi organ failure. No new toxicities were identified. The preliminary responses by tumor type with n ≥ 10 pts are shown in the table below. Responses were seen in OC and RCC at the Cohort 2 dose escalation level (DUR 1/TRE 3 mg/kg). There were 4 cases of SD > 24 weeks: CC, n=2; CRC, n=1; OC, n=1. PD-L1 status was not tested. Conclusions: The DUR + TRE combination has a manageable safety profile, with preliminary evidence of clinical activity. These data support continued study of the combination therapy; the study is ongoing. Clinical trial information: NCT01975831. [Table: see text]

Safety and clinical activity of adenosine A2a receptor (A2aR) antagonist, CPI-444, in anti-PD1/PDL1 treatment-refractory renal cell (RCC) and non-small cell lung cancer (NSCLC) patients

3004

Background: Adenosine production in the tumor leads to immunosuppression through A2aR on infiltrating immune cells. CPI-444 is an oral A2aR antagonist with single agent(SA) anti-tumor activity in pre-clinical models. This phase 1/1b clinical trial uses a 2-step adaptive design to evaluate CPI-444 as a SA and in combination (combo) with the anti-PDL1 antibody, atezolizumab (atezo). We report results of RCC and NSCLC cohorts. Methods: Primary objectives: safety, efficacy and to identify optimal dose/schedule. Step 1 utilized 3 SA and 1 combo cohort to select dose/schedule. Step 2 included disease-specific expansion cohorts including RCC and NSCLC. Eligible pts had selected advanced cancers and failed standard therapies including checkpoint inhibitors. Results: 34 pts have enrolled and 25 pts were evaluable for response (Table 1). Median prior regimens: 3 (range,1-5) and most pts were resistant/refractory to anti PD1/PDL1 therapy (R/R). Most common AEs were Gr 1 nausea (n = 3) and pyrexia (n = 3); Gr 3 tachycardia was the only possibly related SAE. The selected Step 2 doses were CPI-444 100mg BID as a SA and in combo with atezo 840mg IV q2 weeks. The disease control rate (DCR, CR+PR+SD; duration 2 mo to > 8 mo) for pts with RCC and NSCLC cohorts were 86% and 50%, (100% and 43% for R/R pts), respectively. DCRs were similar in the SA and combo cohorts. Of 7 evaluable RCC pts, 1 pt has an ongoing PR (SA cohort, > 4 mo) and 5 have ongoing SD, duration 3 mo to > 8 mo (2 SA, 3 combo). Biopsy of the PR pt showed no detectable tumor and infiltration with CD8+ lymphocytes. In 18 evaluable NSCLC pts, 1 PR (PDL1 negative pt) and 8 SD were seen. PRs and SDs were seen in R/R pts and in PDL1 negative pts in both diseases. Conclusions: CPI-444 is well tolerated and shows anti-tumor activity in RCC and NSCLC pts as a SA and in combo. Pts who are R/R to anti PD1/PDL1 therapy and who are PDL1 negative can also benefit. Clinical trial information: NCT02655822. [Table: see text]

Phase I study of ABBV-399, a c-Met antibody-drug conjugate (ADC), as monotherapy and in combination with erlotinib in patients (pts) with non-small cell lung cancer (NSCLC)

2509

Background: The c-Met receptor is overexpressed in ~50% of pts with NSCLC. ABBV-399 is a first-in-class ADC composed of ABT-700, an anti–c-Met antibody, conjugated to monomethyl auristatin E (a microtubule inhibitor). Preclinical data demonstrate that ABBV-399 can deliver a potent cytotoxin directly to c-Met+ tumor cells. Methods: ABBV-399 was administered at doses ranging from 2.4 to 3.0 mg/kg (dose expansion and combination cohorts at 2.7 mg/kg) once every 21 days to 29 pts with advanced c-Met+ (immunohistochemistry [IHC] H-score ≥150) NSCLC both as monotherapy (ABBV-399/monoT; 16 pts) and in combination with oral erlotinib 150 mg daily (ABBV-399/ERL; 13 pts) (NCT02099058). c-Met overexpression was assessed by IHC utilizing the SP44 antibody (Ventana; Tucson, AZ, USA). Results: As of January 9, 2017, 16 pts with c-Met+ NSCLC received ≥1 dose of ABBV-399/monoT. Monotherapy treatment-related adverse events (TRAEs) occurring in ≥10% of pts (all dose levels and all grades) were fatigue (43.8%), nausea (37.5%), neuropathy (25.0%), vomiting (18.8%), and anemia, constipation, and diarrhea (12.5% each). Three of 16 (19%) ABBV-399–treated c-Met+ NSCLC pts had a confirmed partial response (PR) with duration of response (DOR) 3, 4.5, and 10+ months. At week 12, 6 of 16 pts (37.5%) had disease control. TRAEs in ABBV-399/ERL occurring in ≥10% of pts (all grades) were neuropathy (30.8%), and acneiform rash, diarrhea, fatigue, nausea, and dry skin (15.4% each). Four of 13 (31%) evaluable ABBV-399/ERL–treated c-Met+ pts had a PR (3 confirmed, 1 unconfirmed) with DOR 1+, 2.7, 5.3+, and 11+ months. Three of the 4 pts with PR had EGFR-mutated tumor and recently progressed on TKI. At week 12, 8 of 13 pts (61.5%) had disease control. There were no treatment-related deaths as monotherapy or in combination with erlotinib. Responses were seen in both squamous and non-squamous histology. Conclusions: ABBV-399 is well tolerated at 2.7 mg/kg once every 21 days and has demonstrated antitumor activity in pts with c-Met+ NSCLC both as monotherapy and in combination with erlotinib. Updated efficacy/safety data and MET gene status will be presented. Clinical trial information: NCT02099058.

Clinical trial in progress: A phase 3 study of maintenance bi-shRNA-furin/GM-CSF-expressing autologous tumor cell vaccine in women with stage IIIb-IV high-grade epithelial ovarian cancer

TPS5604

Background: Vigil is an immuno-stimulatory autologous cellular therapy, which uses patient tumor cells transfected with a plasmid encoding genes for GM-CSF and furin (to down regulate TGFβ 1&2). In Phase I, systemic immune activation was demonstrated in the majority of patients using an IFNƔ ELISPOT assay. A randomized Phase 2 assessment of Vigil maintenance therapy vs. observation in ovarian cancer demonstrated prolonged relapse free survival (RFS) (Oh J, Barve M, et al. Gynecologic Oncology, 2016; 143: 504–510.). Based on these observations, a Phase 3 study of maintenance Vigil therapy in patients with advanced ovarian cancer was initiated (NCT02346747). Methods: This is a multicenter, randomized, double-blind, placebo-controlled, Phase 3 study of maintenance Vigil in women with Stage IIIb,c or IV high-grade papillary serous/clear cell/ endometrioid ovarian, fallopian tube or primary peritoneal cancer. Patients will have a minimum of 4 and a maximum of 12 Vigil doses manufactured from tumor obtained at primary debulking surgery. Patients must achieve a complete clinical remission following primary surgery and chemotherapy before being randomized 1:1 to receive either monthly intradermal Vigil or placebo. Randomization is stratified by extent of surgical cytoreduction (complete/microscopic vs. macroscopic residual disease) and neoadjuvant vs. adjuvant chemotherapy. The primary objective is to compare RFS of subjects randomized to Vigil vs. placebo, and the key secondary objective is overall survival (OS). The sample size calculation of 222 patients assumes 24 months for accrual and 36 months of follow-up with a median RFS of 19 months from randomization, in the control group. This provides 90% power to detect a hazard ratio (HR) of 0.6 favoring Vigil at the 0.05 level of significance. To date, 61 patients have been randomized and an additional 55 patients are receiving chemotherapy in anticipation of randomization. Tumor tissue is being obtained from approximately 20 patients per month at multiple sites across the U.S. At their last meeting in January, 2017 the independent DSMB recommended that the study continue without change. Clinical trial information: NCT02346747.

Safety, tumor trafficking and immunogenicity of chimeric antigen receptor (CAR)-T cells specific for TAG-72 in colorectal cancer

Background

T cells engineered to express chimeric antigen receptors (CARs) have established efficacy in the treatment of B-cell malignancies, but their relevance in solid tumors remains undefined. Here we report results of the first human trials of CAR-T cells in the treatment of solid tumors performed in the 1990s.

Methods

Patients with metastatic colorectal cancer (CRC) were treated in two phase 1 trials with first-generation retroviral transduced CAR-T cells targeting tumor-associated glycoprotein (TAG)-72 and including a CD3-zeta intracellular signaling domain (CART72 cells). In trial C-9701 and C-9702, CART72 cells were administered in escalating doses up to 10¹⁰ total cells; in trial C-9701 CART72 cells were administered by intravenous infusion. In trial C-9702, CART72 cells were administered via direct hepatic artery infusion in patients with colorectal liver metastases. In both trials, a brief course of interferon-alpha (IFN-α) was given with each CART72 infusion to upregulate expression of TAG-72.

Results

Fourteen patients were enrolled in C-9701 and nine in C-9702. CART72 manufacturing success rate was 100% with an average transduction efficiency of 38%. Ten patients were treated in CC-9701 and 6 in CC-9702. Symptoms consistent with low-grade, cytokine release syndrome were observed in both trials without clear evidence of on target/off tumor toxicity. Detectable, but mostly short-term (≤14 weeks), persistence of CART72 cells was observed in blood; one patient had CART72 cells detectable at 48 weeks. Trafficking to tumor tissues was confirmed in a tumor biopsy from one of three patients. A subset of patients had ¹¹¹Indium-labeled CART72 cells injected, and trafficking could be detected to liver, but T cells appeared largely excluded from large metastatic deposits. Tumor biomarkers carcinoembryonic antigen (CEA) and TAG-72 were measured in serum; there was a precipitous decline of TAG-72, but not CEA, in some patients due to induction of an interfering antibody to the TAG-72 binding domain of humanized CC49, reflecting an anti-CAR immune response. No radiologic tumor responses were observed.

Conclusion

These findings demonstrate the relative safety of CART72 cells. The limited persistence supports the incorporation of co-stimulatory domains in the CAR design and the use of fully human CAR constructs to mitigate immunogenicity.

Long-term follow-up of DNA engineered bi-shRNA furin GMCSF plasmid/autologous tumor induced immune response in patients with advanced solid tumors (phase I trial)

110

Background: Previously we described safety and evidence of activity to VigilÒ (FANGÒ) and identified relationship of survival advantage to ELISPOT “+” Vigil treated patients (Senzer N et al. Long Term Follow Up: Phase I Trial of “bi-shRNA furin/GMCSF DNA/Autologous Tumor Cell” Immunotherapy (FANG) in Advanced Cancer. J Vaccines Vaccine 2013; 4: 209. doi: 10.4172/2157-7560.1000209). We have updated survival and long-term ELISPOT assessment of this same group of patients. Methods: A non-randomized phase 1 trial of patient treated with Vigil immunotherapy (n=39) compared to a similar matched comparator (MC) group not treated with Vigil (n=35). Results: Trial results suggest survival benefit without evidence of Vigil related toxicity (no ≥ grade 3). γ-IFN ELISPOT served as a biomarker for response and shows correlation with survival. 22/30 evaluable Vigil-treated patients showed ELISPOT conversion (73%) from negative to positive (threshold of ≥10 spots from baseline) during treatment. Durable evidence of γIFN-secreting circulating cytotoxic T cells was observed (up to 30months from treatment start), suggesting induction of memory T effector cells. Survival correlation demonstrated significant benefit of ELISPOT “+” Vigil treated patients (median OS of 784 days, 26.1 months) compared to ELISPOT “-“ patients (median OS of 353 days, 11.77 moths), and supports immune-related survival benefit compared to MC (median OS of 122 days, 4 months), (Table). Conclusions: Vigil immunotherapy induces a significant immune response. Detailed analysis of the immune effector population phenotype is underway to determine optimal correlation with survival. Clinical trial information: NCT01061840. [Table: see text]

Efficacy/safety analysis of a phase 2 study of ruxolitinib (Rux) + regorafenib (Re) in patients (pts) with relapsed/refractory (r/r) metastatic colorectal cancer (mCRC)

663

Background: The JAK-STAT pathway plays a role in the systemic inflammatory response in CRC. Rux, a potent JAK1/2 inhibitor, was evaluated in r/r mCRC pts. Methods: After a safety run-in (Rux 20 mg BID + Re 160 mg QD), pts were randomized to Rux 15 mg BID or placebo (Pb) + Re 160 mg QD. Rux could be titrated to 20 mg BID. The randomized phase included Substudy 1 (S1, pts with C-reactive protein [CRP] > 10 mg/L) and Substudy 2 (S2, pts with CRP ≤ 10 mg/L). Primary endpoint: OS. Results: Rux 20 mg BID was well tolerated in the safety run-in (n = 11). 396 pts were randomized (S1: n = 175; S2: n = 221). Median age in Rux vs (v) Pb groups: 62 v 60 yr (S1), 59 v 61 yr (S2). Most pts had ≥ 3 prior chemotherapy regimens: 85% v 84% (S1); 81% v 78% (S2). Median treatment durations: 57 d with Rux v 56 d with Pb (S1), 106 d with Rux v 56 d with Pb (S2). Discontinuations were mainly due to disease progression (S1: 61% v 63%, S2: 62% v 66%) or AEs (S1: 10% v 19%, S2: 9% v 9%). Rux + Re did not improve OS/PFS over Re + Pb in S1/S2 (see Table). S1 was terminated for futility at interim analysis; S2 was terminated per sponsor decision. The number of events required for final efficacy analysis was reached in S1, not in S2. Most common non-hematologic AEs (Rux v Pb): palmar-plantar erythrodysesthesia syndrome (PPES; S1: 42% v 44%; S2: 58% v 47%), diarrhea (S1: 38% v 31%; S2: 39% v 27%), decreased appetite (S1: 37% v 36%; S2: 26% v 33%), fatigue (S1: 34% v 36%; S2: 41% v 44%), hypertension (S1: 21% v 26%; S2: 42% v 40%). Most common grade (G) 3/4 non-hematologic AEs: PPES (S1: 13% v 15%; S2: 17% v 13%) and hypertension (S1: 9% v 7%; S2: 22% v 16%). Most common G 3/4 hematologic AEs (new/worsening lab abnormalities): lymphopenia (S1: 13% v 8%; S2: 14% v 7%) and anemia (S1: 4% v 5%; S2: 9% v 4%). Conclusions: Rux + Re did not improve OS/PFS in mCRC pts over Re alone. There was a nonsignificant trend towards improved OS/PFS in S2. Rux 15-20 mg BID safety profile was consistent with previous studies in other tumors. Clinical trial information: NCT02119676. [Table: see text]

Abstract CT083: A pivotal randomized phase II study of anetumab ravtansine or vinorelbine in patients with advanced or metastatic pleural mesothelioma after progression on platinum/pemetrexed-based chemotherapy (NCT02610140)

Background: Mesothelioma is a rare but aggressive cancer with a 5-year survival rate less than 10%. Mesothelin is a protein normally present on mesothelial cells and overexpressed in the majority of mesotheliomas. Anetumab ravtansine (BAY 94-9343) is a novel fully human anti-mesothelin IgG1 antibody conjugated to ravtansine, an antitubulin cytotoxic agent. In a phase I study, anetumab ravtansine at 6.5 mg/kg on a q3w IV schedule was well tolerated and showed encouraging durable tumor responses in patients with previously treated mesothelioma.

Design: A randomized, open-label, active-controlled, 2-arm, multicenter, phase II trial to evaluate the efficacy and safety of anetumab ravtansine at 6.5 mg Q3W versus vinorelbine 30 mg/m2 QW in patients with advanced or metastatic malignant pleural mesothelioma overexpressing mesothelin and who have progressed on first-line platinum/pemetrexed-based chemotherapy.

Objectives: The primary objective is to test the superiority of anetumab ravtansine monotherapy over vinorelbine in progression-free survival (PFS). The secondary objectives of this study include overall survival, patient-reported outcomes (PRO), tumor response, and safety. Exploratory objectives include immunogenicity of anetumab ravtansine, pharmacokinetics, and biomarkers of response.

Methods: Biomarker sampling will be performed on all patients to measure tumor mesothelin expression levels at prescreening. Biomarker-positive patients with moderate (2+) and/or strong (3+) level in at least 30% of tumor cells will be randomized and start study treatment following progression after 1st line treatment of platinum/pemetrexed (with or without bevacizumab).

Approximately 183 patients meeting eligibility criteria will berandomized in a 2:1 ratio to receive anetumab ravtansine or vinorelbine. Randomization will be stratified by geographic region (Rest of World v. Asia) and time to progression on 1st line treatment (? 6 months vs &lt; 6 months). The primary endpoint, PFS per modified RECIST criteria for metastatic pleural mesothelioma per central review, will be tested using a log-rank test stratified by randomization strata, with 1-sided significance level 0.0125. The primary analysis will occur after approximately 117 PFS events. Assuming true median PFS of 3.6 months under vinorelbine treatment, the primary hypothesis test is designed to detect a 100% prolongation of true PFS (median 7.2 months) with 90% power. Novel study methods include a grading system for AEs of special interest and the PRO instrument.

Results: This trial is open and currently accruing patients.

Citation Format: Raffit Hassan, John J. Nemunaitis, Jan P. van Meerbeeck, Ross Jennens, George R. Blumenschein, Jr, Dean A. Fennell, Hedy L. Kindler, Silvia Novello, Cem Elbi, Annette Walter, Danila Serpico, Emma Fountain, Sandra Vingerhoedt, Christine Brown, Jonathan Siegel, Barrett H. Childs. A pivotal randomized phase II study of anetumab ravtansine or vinorelbine in patients with advanced or metastatic pleural mesothelioma after progression on platinum/pemetrexed-based chemotherapy (NCT02610140). [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 CT083.

Cutaneous head and neck melanoma in OPTiM, a randomized phase 3 trial of talimogene laherparepvec versus granulocyte-macrophage colony-stimulating factor for the treatment of unresected stage IIIB/IIIC/IV melanoma

Background

Cutaneous head and neck melanoma has poor outcomes and limited treatment options. In OPTiM, a phase 3 study in patients with unresectable stage IIIB/IIIC/IV melanoma, intralesional administration of the oncolytic virus talimogene laherparepvec improved durable response rate (DRR; continuous response ≥6 months) compared with subcutaneous granulocyte‐macrophage colony‐stimulating factor (GM‐CSF).

Methods

Retrospective review of OPTiM identified patients with cutaneous head and neck melanoma given talimogene laherparepvec (n = 61) or GM‐CSF (n = 26). Outcomes were compared between talimogene laherparepvec and GM‐CSF treated patients with cutaneous head and neck melanoma.

Results

DRR was higher for talimogene laherparepvec–treated patients than for GM‐CSF treated patients (36.1% vs 3.8%; p = .001). A total of 29.5% of patients had a complete response with talimogene laherparepvec versus 0% with GM‐CSF. Among talimogene laherparepvec–treated patients with a response, the probability of still being in response after 12 months was 73%. Median overall survival (OS) was 25.2 months for GM‐CSF and had not been reached with talimogene laherparepvec.

Conclusion

Treatment with talimogene laherparepvec was associated with improved response and survival compared with GM‐CSF in patients with cutaneous head and neck melanoma. © 2016 Wiley Periodicals, Inc. Head Neck38: 1752–1758, 2016