Clinical trial links oncolytic immunoactivation to survival in glioblastoma

Immunotherapy failures can result from the highly suppressive tumour microenvironment that characterizes aggressive forms of cancer such as recurrent glioblastoma (rGBM)1,2. Here we report the results of a first-in-human phase I trial in 41 patients with rGBM who were injected with CAN-3110-an oncolytic herpes virus (oHSV)3. In contrast to other clinical oHSVs, CAN-3110 retains the viral neurovirulence ICP34.5 gene transcribed by a nestin promoter; nestin is overexpressed in GBM and other invasive tumours, but not in the adult brain or healthy differentiated tissue4. These modifications confer CAN-3110 with preferential tumour replication. No dose-limiting toxicities were encountered. Positive HSV1 serology was significantly associated with both improved survival and clearance of CAN-3110 from injected tumours. Survival after treatment, particularly in individuals seropositive for HSV1, was significantly associated with (1) changes in tumour/PBMC T cell counts and clonal diversity, (2) peripheral expansion/contraction of specific T cell clonotypes; and (3) tumour transcriptomic signatures of immune activation. These results provide human validation that intralesional oHSV treatment enhances anticancer immune responses even in immunosuppressive tumour microenvironments, particularly in individuals with cognate serology to the injected virus. This provides a biological rationale for use of this oncolytic modality in cancers that are otherwise unresponsive to immunotherapy (ClinicalTrials.gov: NCT03152318 ).

CTIM-09. ENRICHED TCR/BCR VDJ REARRANGEMENTS CORRELATE WITH MRI AND SURVIVAL OUTCOMES IN PATIENTS WITH RECURRENT HIGH-GRADE GLIOMA TREATED WITH CAN-3110

BACKGROUND

CAN-3110 (rQNestin34.5v2) is an HSV-1 oncolytic viral immunotherapy with one copy of the inflammatory ICP34.5 gene under transcriptional control of the Nestin glioma-specific promoter. We completed a phase 1 sequential dose-escalation trial of CAN-3110 in recurrent high-grade glioma (rHGG).

METHODS

CAN-3110 was injected intratumorally starting at 1x106 plaque forming units (pfu) and dose- escalated by half log up to 1x1010 pfu in biopsy confirmed rHGG. An expansion cohort of 12 patients was then accrued at 1x109 pfus. Blood and post-injection rHGG were collected.

RESULTS

41 rHGG patients were treated (42 separate interventions): median age 56 years (range 27-74); 21 females, 20 males; median baseline KPS 90 (range 70-100). CAN-3110 administration was well-tolerated with no dose limiting toxicities. Median overall survival (mOS) was 11.9 months. Histologic and molecular analyses showed significantly increased T cell infiltration in post treatment samples with elevated T cell and/or B cell receptor (TCR/BCR) transcripts which correlated with patient survival (HR 0.26 for patients with elevated TCR/BCR rearrangements as compared to patients with low). Volumetric analyses of MRI suggest a trend between reduction in the relative change in tumor growth, TCR/BCRs enrichment and survival in CAN-3110 treated patients.

CLINICAL IMPLICATIONS

Administration of CAN-3110 into rHGG was well tolerated. OS of CAN-3110 treated subjects compare favorably to historical controls. The association of increased TCR/BCR transcripts with survival suggests that CAN-3110 induces T cell responses against rHGG, supporting further clinical development of CAN-3110 viral immunotherapy.

First report of safety/tolerability and preliminary antitumor activity of CAN-2409 in inadequate responders to immune checkpoint inhibitors for stage III/IV NSCLC

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Background: Immune checkpoint inhibitors (ICI) are standard of care for advanced NSCLC. Even among patients with initial response, a majority ultimately progress, and rational combination approaches are needed to improve outcomes. CAN-2409 is a replication-deficient adenoviral gene construct that delivers the thymidine kinase gene, resulting in local conversion of a prodrug (valacyclovir) into a toxic metabolite. This leads to tumor cell lysis and immunization against the injected tumor and uninjected metastases. We have previously shown that monotherapy intra-tumoral (IT) delivery of CAN-2409 followed by oral valacyclovir in NSCLC patients is safe and results in CD8+ T cell infiltration in the injected tumor and activation of this cell population in tissue and peripheral blood. Methods: This open-label Ph2 experimental medicine clinical trial evaluates safety and clinical activity of IT CAN-2409 combined with ICI (± chemo) for stage III/IV NSCLC. Three cohorts are defined based on response to ICI at enrollment: stable disease (SD; Cohort 1; C1), progressive disease (PD) after ≥18 weeks (w) of ICI (Cohort 2; C2), or ICI refractory disease (RD; Cohort 3; C3). Two doses of CAN-2409 (5x1011 vp) are given 5-7w apart via bronchoscopic or percutaneous injection into a lung tumor, disease-positive lymph node or peripheral metastasis, followed by valacyclovir. Patients are assessed for safety, immunologic biomarkers (analysis in progress), and clinical response. Results: As of data cutoff (10Jan22), 28 patients received ≥1 dose of CAN-2409 (safety population). Median age was 70 years; 86% stage IV; 32% squamous; 11% PD-L1 >50%; 82% receiving pembrolizumab and 18% nivolumab. Study treatment and procedures were generally well tolerated. The most common TRAEs were Gr1/2, with fatigue, fever, and chills in 18-39% of patients; 1 patient had Gr3 fever. Twenty-two patients are alive and 6 patients died due to disease. Of the 14 RECIST evaluable patients who received 2 doses of CAN-2409, clinical response was seen in 4 patients (Table 1). Two PRs are ongoing (6w, 24w) and reduction in tumor size was observed in non-injected lesions. In C2, 6 of 7 patients achieving SD are ongoing with median duration of 13w (range 10-40w). Conclusions: The addition of CAN-2409 for patients with advanced NSCLC and inadequate response to front-line ICI (± chemo) appears to be well tolerated. Preliminary clinical data suggest that CAN-2409 induced a clinical response in 4/14 evaluable patients and produced disease stabilization in most patients entering the trial with PD, with evidence of abscopal effect in a subset of patients. Clinical trial information: NCT04495153. [Table: see text]

CTIM-13. PHASE 1 CLINICAL TRIAL OF ONCOLYTIC VIRAL IMMUNOTHERAPY WITH CAN-2409 + VALACYCLOVIR IN COMBINATION WITH NIVOLUMAB AND STANDARD OF CARE (SOC) IN NEWLY DIAGNOSED HIGH-GRADE GLIOMA (HGG)

BACKGROUND

CAN-2409 is a replication-deficient adenovirus that delivers HSV thymidine kinase to cancer cells, resulting in local conversion of orally administered valacyclovir into a toxic metabolite. Previously, a phase 1b/2 clinical trial of CAN-2409 combined with standard-of-care (SOC) demonstrated safety and improved survival in HGG patients. Addition of CAN-2409 to nivolumab has the potential to activate locally recruited lymphocytes and teach them to recognize tumor neoantigens, changing the ‘cold’ immunosuppressive tumor microenvironment, and synergizing with the activity mediated by immune checkpoint inhibitors. This notion is supported by preclinical experiments showing that the combination of CAN-2409 with anti-PD1 therapy was more effective than either treatment alone.

METHODS

This ongoing phase 1 clinical trial evaluates safety and initial efficacy of CAN-2409 combined with nivolumab and SOC in newly diagnosed HGG. CAN-2409 is injected during neurosurgery into the tumor bed, followed by 14-days of valacyclovir. Radiation starts within 8 (+/-4) days of surgery. Temozolomide is administered to MGMT-methylation positive patients only. Nivolumab is given every 2 weeks, up to 52-weeks. Deep immune profiling studies are ongoing and initial results will be available shortly.

RESULTS

From February 2019 to March 2021, 41 patients were enrolled and 35 were evaluable for safety from the combination of CAN-2409, nivolumab and SOC: 24 male and 11 female; 34 glioblastoma, 1 diffuse astrocytoma; 33 IDH-wildtype, 2 IDH-mutant; 15 MGMT-methylated, 20 unmethylated. Median age was 62-years (range 28-79), median KPS 90 (range 80-100). With 13 months median follow-up, no unexpected serious adverse events were observed, and 23 patients are still alive. The most frequent possibly related adverse events (>10%) were nausea, fatigue, fever, headache, and increased ALT.

CONCLUSIONS

The combination of CAN-2409 + nivolumab + SOC was well tolerated. Clinical follow-up and extensive biomarker analyses will provide a better understanding of the therapeutic potential of this approach.

Survival disparities following surgery among patients with different histological types of non-small cell lung cancer

OBJECTIVES

Clinical decisions for NSCLC patients are often based on TNM stage, which does not account for different histological subtype. Whether histological subtype affects survival still remains unclear. The main objective of this study was to determine the extent to which the survival outcomes of patients with early-stage NSCLC differ by histological subtype.

MATERIAL AND METHODS

Retrospective cohort study of SEER data base. Patients with stage IA and IB NSCLC that underwent surgery with lymph node dissection were included. The primary outcome was the time to death. Cox proportional hazards models were used to identify risk factors associated with overall survival (OS). The secondary outcome was the time to death from lung cancer. A Cox model and a Fine-Gray subdistribution hazards model in which death from causes other than lung cancer was considered a competing risk event were used to identify risk factors for death from lung cancer.

RESULTS

Analysis of the SEER database identified 28,584 NSCLC patients, of whom 19,750 (69 %) had adenocarcinoma and 8834 (31 %) had squamous cell carcinoma. In the multivariate for OS, older age (p < 0.001), male gender (p < 0.001), pneumonectomy (p < 0.001), larger tumor size (p < 0.001), squamous cell carcinoma (p < 0.001) not being Hispanic or Asian were associated with increased risk of death. In the competing risk model, older age (p < 0.001), male gender (p < 0.001), pneumonectomy (p < 0.001), larger tumor size (p < 0.001), and squamous cell carcinoma (p < 0.001) were was associated with an increased risk of death from lung cancer.

CONCLUSION

This study suggests that among patients with stage I NSCLC, those with squamous histology have a higher risk of mortality than those with adenocarcinoma histology taking into account competing risks.