Naik, Shruthi

Abstract Background: We previously reported successful treatment of myeloma with an oncolytic virus, MMV-NIS. Preexisting immunity against measles made use of that virus unsatisfactory. The Indiana strain of Vesicular Stomatitis Viruses (VSV) are being developed as anticancer drugs for the treatment of a variety of malignancies. To ensure tumor selective replication and spread, we designed the VSV to encode interferon beta. Expression of IFNβ also serves as a STING agonist to activate host immunity against the cancer. The sodium iodide symporter (NIS) is inserted as a reporter gene into the viral genome to enable noninvasive monitoring of viral spread using PET/CT imaging. We report a Phase I clinical trial of intravenous administration of VSV-IFNβ-NIS for relapsed hematological malignancies including MM, AML, and TCL. Methods: Arm A consisted of patients with low tumor burden. Arm B included patients with high tumor burden. Both arms consisted of a classical 3+3 phase I trial, starting at 5x10^9 TCID50 (dose level 1) through 5x10^11 TCID50 (dose level 4), given as a single IV dose. In order to obviate potential toxicity from high interferon levels, Arm B received ruxolitinib 15 mg twice daily for 10 days beginning on day -1. The primary objective was determining the maximum tolerated dose (MTD) of VSV-IFNβ-NIS alone and in combination with ruxolitinib; secondary objectives include estimating the safety profile and preliminary efficacy. Correlative objectives include monitoring the pharmacodynamics of viral replication through SPECT/CT imaging with NIS gene, viremia, virus shedding, changes in the immune profile of peripheral blood leukocytes, and immunohistochemistry for immune cell infiltrates in tumors. Adverse events (AEs) are reported herein based on CTCAE v4 with the exception of cytokine release syndrome (CRS) which is based on Lee (Blood 2014; 124(2):188-195) criteria. Results: To date, 10 patients have received IV VSV-IFNβ-NIS; 8 in Arm A and 2 in Arm B. In Arm A, 3 patients were treated at dose level 1, 3 at dose level 2 and 2 at dose level 3. At dose level 1, there were three grade 3 hematologic AEs (neutropenia [1], lymphopenia [2]), and no grade 3+ non-hematologic AEs. At dose level 2, there were two grade 3 hematologic AEs (anemia [1], lymphopenia [1]), and two grade 3 non-hematologic AEs (nausea [1], dehydration [1]). A grade 2 CRS by Lee criteria was also observed. At dose level 3, 2 patients have been enrolled and data are maturing for DLT evaluation. In Arm B (VSV + rux), 2 patients have been enrolled and data are maturing for dose limiting toxicity (DLT) evaluation. Other grade 1 and 2 toxicities have included fever, hypertension, headache, electrolyte abnormalities, nausea, vomiting, transient elevation of liver function tests and creatinine. All grade 1 and 2 toxicities resolved within 72 hours. Among the 6 patients evaluable for response, there was one partial remission (TCL patient treated at dose level 2), and 5 with progressive disease. Multiple cytokines increased at 4h post infusion of virus, but most returned to baseline levels by 24h.Viremia was detectable in all patients at the end of infusion, and to varying levels at 30 mins, 1, 2, 4, 24, 48h or 72 hours post virus infusion. No persistent viremia was observed. No infectious virus was recovered in buccal swabs or urine and neutralizing anti-VSV antibodies were present by day 29. Extensive immune phenotyping and ELIspot assays for shared antigens are ongoing. Conclusion: In the lowest dose levels tested to date, VSV-IFNβ-NIS has not led to any observed dose limiting toxicity. Dose escalation is ongoing and updated results will be reported. Disclosures Lacy: Celgene: Research Funding. Peng:Vyriad: Equity Ownership. Russell:Vyriad: Equity Ownership. Dueck:Bayer: Employment; Phytogine: Employment; Pfizer: Honoraria. Witzig:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Dispenzieri:Celgene, Takeda, Prothena, Jannsen, Pfizer, Alnylam, GSK: Research Funding. Gertz:spectrum: Consultancy, Honoraria; Physicians Education Resource: Consultancy; Ionis: Honoraria; janssen: Consultancy; Medscape: Consultancy; celgene: Consultancy; Apellis: Consultancy; Prothena: Honoraria; Amgen: Consultancy; annexon: Consultancy; Abbvie: Consultancy; Research to Practice: Consultancy; Teva: Consultancy; Alnylam: Honoraria. Dingli:Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Millennium Takeda: Research Funding; Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Millennium Takeda: Research Funding. Kapoor:Celgene: Research Funding; Takeda: Research Funding. Al-Kali:Novartis: Research Funding. Naik:Vyriad: Equity Ownership. Kumar:AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract Abstract 378 The need for new and more effective long-term treatments for Multiple Myeloma (MM) has led to the utilization and engineering of replication competent (oncolytic) viruses as potential therapies. Vesicular stomatitis virus (VSV) is a potent oncolytic agent with several features that make it a favorable choice as a potential myeloma therapy. Specifically, (i) VSV replicates rapidly and can be grown to high titers (for effective clinical use) (ii) VSV undergoes transcription and replication exclusively in the cytoplasm avoiding host genome integration (iii) there is low/absent pre-existing immunity against VSV among the general population, (iv) naturally occurring human VSV infections are generally asymptomatic or result in minimal flu-like symptoms, (v) VSV is not easily transmitted between individuals (natural transmission is by hematophagous insects). Previously we showed weak oncolytic efficacy with an attenuated strain of VSV coding for the sodium iodide symporter (NIS) gene, VSV-D51-NIS, in the immune competent 5TGM1 syngeneic MM mouse model (C57Bl/KalwRijHsd) (Goel at. al. Blood. 2007 Oct 1;110(7):2342-50). Since VSV replication is strongly inhibited by IFN-induced innate immune responses in normal cells, but not in myeloma cells and IFN has known anti-myeloma activity, we hypothesized that the IFN-coding VSVs would be safer and more potent than previously tested VSV recombinants. We therefore constructed and tested the efficacy of VSVs coding for b-Interferon (VSV-IFN) or b-IFN and NIS (VSV-IFN-NIS). Interestingly, all of the newly constructed viruses, including VSV-IFN-NIS, showed greatly superior replication kinetics compared to the previously reported VSV-D51-NIS virus. Furthermore, compared to VSV-D51-NIS, VSV-IFN-NIS vectors induced higher NIS expression in vitro. In vivo therapy studies showed that a single intravenous dose of each of the IFN-coding VSVs promoted tumor regression and significantly prolonged survival of immunocompetent mice bearing subcutaneous or orthotopic 5TGM1 myeloma tumors. Tc-99m imaging studies conducted in mice treated with VSV-IFN-NIS, showed tumor specific virus mediated NIS expression and radio-isotope uptake that increased concurrently with intratumoral viral spread. Most importantly, there was no evidence of neurotoxicity following treatment with the IFN-coding VSVs. These studies indicate that VSV-IFN-NIS has potential as a novel therapeutic agent for multiple myeloma that can be combined with radio-isotopes for both non-invasive imaging of viral biodistribution and radiovirotherapy. A phase I clinical study is currently planned. Disclosures: No relevant conflicts of interest to declare.

Osteosarcoma is the most common primary tumor of bone. Osteosarcomas are rare in humans, but occur more commonly in dogs. A comparative approach to studying osteosarcoma has highlighted many clinical and biologic aspects of the disease that are similar between dogs and humans; however, important species-specific differences are becoming increasingly recognized. In this review, we describe risk factors for the development of osteosarcoma in dogs and humans, including height and body size, genetics, and conditions that increase turnover of bone-forming cells, underscoring the concept that stochastic mutational events associated with cellular replication are likely to be the major molecular drivers of this disease. We also discuss adaptive, cancer-protective traits that have evolved in large, long-lived mammals, and how increasing size and longevity in the absence of natural selection can account for the elevated bone cancer risk in modern domestic dogs.

Abstract Clinical translation of intravenous therapies to treat disseminated or metastatic cancer is imperative. Comparative oncology, the evaluation of novel cancer therapies in animals with spontaneous cancer, can be utilized to inform and accelerate clinical translation. Preclinical murine studies demonstrate that single-shot systemic therapy with a vesicular stomatitis virus (VSV)-IFNβ-NIS, a novel recombinant oncolytic VSV, can induce curative remission in tumor-bearing mice. Clinical translation of VSV-IFNβ-NIS therapy is dependent on comprehensive assessment of clinical toxicities, virus shedding, pharmacokinetics, and efficacy in clinically relevant models. Dogs spontaneously develop cancer with comparable etiology, clinical progression, and response to therapy as human malignancies. A comparative oncology study was carried out to investigate feasibility and tolerability of intravenous oncolytic VSV-IFNβ-NIS therapy in pet dogs with spontaneous cancer. Nine dogs with various malignancies were treated with a single intravenous dose of VSV-IFNβ-NIS. Two dogs with high-grade peripheral T-cell lymphoma had rapid but transient remission of disseminated disease and transient hepatotoxicity that resolved spontaneously. There was no shedding of infectious virus. Correlative pharmacokinetic studies revealed elevated levels of VSV RNA in blood in dogs with measurable disease remission. This is the first evaluation of intravenous oncolytic virus therapy for spontaneous canine cancer, demonstrating that VSV-IFNβ-NIS is well-tolerated and safe in dogs with advanced or metastatic disease. This approach has informed clinical translation, including dose and target indication selection, leading to a clinical investigation of intravenous VSV-IFNβ-NIS therapy, and provided preliminary evidence of clinical efficacy and potential biomarkers that correlate with therapeutic response. Mol Cancer Ther; 17(1); 316–26. ©2017 AACR.

ABSTRACT Measles virus (MV) entry requires at least 2 viral proteins, the hemagglutinin (H) and fusion (F) proteins. We describe the rescue and characterization of a measles virus with a specific mutation in the stalk region of H (I98A) that is able to bind normally to cells but infects at a lower rate than the wild type due to a reduction in fusion triggering. The mutant H protein binds to F more avidly than the parent H protein does, and the corresponding virus is more sensitive to inhibition by fusion-inhibitory peptide. We show that after binding of MV to its receptor, H-F dissociation is required for productive infection.

Multiple myeloma is a radiosensitive malignancy that is currently incurable. Here, we generated a novel recombinant vesicular stomatitis virus [VSV(Δ51)-NIS] that has a deletion of methionine 51 in the matrix protein and expresses the human sodium iodide symporter (NIS) gene. VSV(Δ51)-NIS showed specific oncolytic activity against myeloma cell lines and primary myeloma cells and was able to replicate to high titers in myeloma cells in vitro. Iodide uptake assays showed accumulation of radioactive iodide in VSV(Δ51)-NIS–infected myeloma cells that was specific to the function of the NIS transgene. In bg/nd/xid mice with established subcutaneous myeloma tumors, administration of VSV(Δ51)-NIS resulted in high intratumoral virus replication and tumor regression. VSV-associated neurotoxicity was not observed. Intratumoral spread of the infection was monitored noninvasively by serial gamma camera imaging of 123I-iodide biodistribution. Dosimetry calculations based on these images pointed to the feasibility of combination radiovirotherapy with VSV(Δ51)-NIS plus 131I. Immunocompetent mice with syngeneic 5TGM1 myeloma tumors (either subcutaneous or orthotopic) showed significant enhancements of tumor regression and survival when VSV(Δ51)-NIS was combined with 131I. These results show that VSV(Δ51)-NIS is a safe oncolytic agent with significant therapeutic potential in multiple myeloma.