George M. Gill

A phase I study of the combination of intravenous reovirus type 3 Dearing and gemcitabine in patients with advanced cancer.

Purpose: This study combined systemic administration of the oncolytic reovirus type 3 Dearing (reovirus) with chemotherapy in human subjects. We aimed to determine the safety and feasibility of combining reovirus administration with gemcitabine and to describe the effects of gemcitabine on the antireoviral immune response. Experimental Design: Patients received reovirus in various doses, initially we dosed for five consecutive days but this was poorly tolerated. We amended the protocol to administer a single dose and administered up to 3 × 1010 TCID50. Toxicity was assessed by monitoring of clinical and laboratory measurements. We assessed antibody response by cytotoxicity neutralization assay. Results: Sixteen patients received 47 cycles of reovirus. The two initial patients and one patient in the final cohort experienced dose limiting toxicity (DLT). The DLTs consisted of two asymptomatic grade 3 liver enzyme rises and one asymptomatic grade 3 troponin I rise. Common toxicities consisted of known reovirus and gemcitabine associated side effects. Further analysis showed a potential interaction between reovirus and gemcitabine in causing liver enzyme rises. Grade 3 rises in liver enzymes were associated with concomitant aminocetophen use. Importantly, the duration of the liver enzyme rise was short and reversible. Neutralizing antibody responses to reovirus were attenuated both in time-to-occurrence and peak height of the response. Conclusions: Reovirus at the dose of 1 × 1010 TCID50 can be safely combined with full dose gemcitabine. Combination of reovirus with gemcitabine affects the neutralizing antibody response and this could impact both safety and efficacy of this treatment schedule. Clin Cancer Res; 17(3); 581–8. ©2010 AACR.

Phase 1 Clinical Trial of Intratumoral Reovirus Infusion for the Treatment of Recurrent Malignant Gliomas in Adults

Reovirus, an oncolytic RNA virus exhibiting antiglioma activity, was shown in a previous single institution phase 1 study found that the inoculation of the virus to be well tolerated in patients with recurrent malignant glioma (MG). The goals of multicenter study reported herein were to determine the dose-limiting toxicity, maximum tolerated dose, and target lesion response rate when reovirus was administered in a novel fashion via intratumoral infusion for 72 hours in patients with recurrent malignant glioma. Fifteen adult patients were treated in a dose escalation study ranging from 1 × 10(8) to 1 × 10(10) tissue culture infectious dose 50, tentimes the dose achieved in the previous trial. Neurological, functional examinations, and imaging studies were completed pre- and postinfusion. There was one grade 3 adverse event (convulsions) felt to be possibly related to treatment, but no grade 4 adverse events considered probably or definitely related to treatment. Dose-limiting toxicity were not identified and a maximum tolerated dose was not reached. Evidence of antiglioma activity was seen in some patients. This first report of intratumoral infusion of reovirus in patients with recurrent malignant glioma demonstrated the approach to be safe and well tolerated, warranting further studies.

Oncolytic reovirus in combination with chemotherapy in metastatic or recurrent non–small cell lung cancer patients with KRAS-activated tumors

The type 3 Dearing reovirus (Reolysin) is a naturally occurring virus that preferentially infects and causes oncolysis in tumor cells with a Ras‐activated pathway. It induces host immunity and cell cycle arrest and acts synergistically with cytotoxic agents.

Phase I Trial of Cyclophosphamide as an Immune Modulator for Optimizing Oncolytic Reovirus Delivery to Solid Tumors

Purpose: Reovirus is a wild-type oncolytic virus that is ubiquitous in the environment; most patients are therefore preimmune. Therapeutic administration leads to an increase in neutralizing antireovirus antibody (NARA) titer. We hypothesized that if NARA limited reovirus antitumor activity, the effect might be attenuated by coadministration of cyclophosphamide. Experimental design: In a phase I study, patients with advanced cancer received cyclophosphamide 3 days before intravenous reovirus serotype 3 Dearing (RT3D). The primary objective was to reduce the resulting rise in NARA titer. Cyclophosphamide dose was escalated from 25–1,000 mg/m2 through nine cohorts; we aimed to define a well-tolerated immunomodulatory dose. Results: The combination was well tolerated in 36 patients, with grade 3/4 toxicities only seen at or above the maximum tolerated dose of cyclophosphamide, which was 800 mg/m2 combined with reovirus. Immunosuppressive effect, defined as maintaining NARA titer rise below a predefined threshold, was observed in only one patient. Furthermore, despite expected myelosuppression seen at higher cyclophosphamide doses, no changes in T-cell subsets, including Tregs, occurred with dose escalation. Viable virus was detected in association with peripheral blood mononuclear cells (PBMC) from 14% of patients 10 days after the last RT3D injection, despite high plasma NARA titer, demonstrating a potential mechanism for prolonged evasion of neutralization by reovirus. Conclusions: Coadministration of cyclophosphamide with reovirus is safe, but does not attenuate host antiviral responses. Alternative immunomodulation approaches should be explored, but association with PBMCs may allow reovirus to persist and evade even high levels of neutralizing antibodies. Clin Cancer Res; 21(6); 1305–12. ©2014 AACR.

Abstract C22: A phase II study of intravenous wild-type reovirus (Reolysin®) in combination with paclitaxel plus carboplatin in patients with platinum refractory metastatic and/or recurrent squamous cell carcinoma of the head and neck.

Purpose: REOLYSIN® (Reovirus serotype 3) is a Dearing strain, naturally occurring ubiquitous human reovirus. In transformed cells with activated RAS pathway, this reovirus causes preferential lysis due to the inhibition of RNA-activated protein kinase (PKR) in these cells. In a phase-I dose escalation trial three of six patients with squamous cell cancer of the head and neck showed significant responses in combination with chemotherapy leading to the design of this phase-II study. Methods: A single arm, open-label, phase-II study of REOLYSIN 3 × 10 10 TCID 50 given intravenously Days 1–5, with paclitaxel (175 mg/m 2 ) and carboplatin (AUC 5) on Day-1 every three weeks was conducted in patients with platinum-refractory recurrent and/or metastatic squamous cell cancers of the oral cavity, larynx, or pharynx. The primary end point was to determine the objective response rate (CR + PR) of the treatment regimen in the study population. Secondary objectives included the determination of disease control rate (CR + PR + SD) and the safety and tolerability of the treatment regimen. Patients were required to have measurable disease and evaluation of tumor status was conducted at baseline and every other cycle. Results: Since September 2008, 14 patients age 29–61 (median 54) were enrolled and received a total of 57 cycles (range 1–10). Thirteen of 14 patients were ECOG performance status 0 or 1 and 1 was ECOG 2. All patients were platinum-refractory and received other prior chemotherapy, radiotherapy, or combinations for their metastatic or recurrent disease. Ten of 14 patients received prior treatment with taxanes. Sites of disease included larynx (3), oral cavity (6), and pharynx (4), and other site (1). Side effects were mild to moderate (Grade 1–2) including constitutional symptoms, fever, chills, and fatigue. Grade-3 toxicities included hypokalemia (2 patients), fatigue (1), nausea (1), and AST elevation (1). Hematological side effects included Gr-4 neutropenia in 1 patient, Gr-3 neutropenia in 5 patients, and Gr-3 anemia in 3 patients. Thirteen patients were evaluable for response. Four partial responses were seen for an objective response rate of 31%. Two patients had SD for ≥12 weeks for a disease control rate of 46%.Two of the 4 patients with PR and both patients with SD had received prior treatment with taxanes. Conclusion: REOLYSIN in combination with paclitaxel and carboplatin showed significant activity in patients with platinum-refractory head and neck cancer. An international, randomized, double-blind Phase-III trial of the combination for this target population is under way. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C22.

Abstract C70: A phase 2 study of intravenous administration of REOLYSIN® (reovirus type 3 dearing) in combination with paclitaxel (P) and carboplatin (C) in patients with squamous cell carcinoma of the lung.

Background: REOLYSIN is a unique, dearing strain oncolytic live virus which has demonstrated the ability to replicate in tumor cells with an activated RAS pathway. It has synergistic antitumor activity in combination with chemotherapy in both preclinical and clinical studies. Based on the promising activity of the combination of REOLYSIN with P/C in 2 trials in SCC of the head and neck, we elected to test this regimen in this Phase 2 trial in SCCLung. Methods: Goals of this single-arm, open-label phase II study were to determine, first, the objective response rate (ORR) and second, the 6-month progression-free survival (PFS) and the overall survival (OS) of patients with metastatic or recurrent squamous cell carcinoma of the lung, treated with REOLYSIN in combination with standard doses of P/C. The study had a two-stage design, with 19 patients in the first stage. The trial would be terminated if 3/19 or fewer patients obtained an objective response. If the trial continued to the second stage, a total of up to 36 patients would be studied. The primary endpoint wouldbe met if patients in both stages had an ORR of at least 35%. Eligible patients had ECOG PS 0-2, adequate organ function, and no prior systemic chemotherapy for their metastatic or recurrent disease. Prior adjuvant chemotherapy or chemo-XRT for treatment of primary disease was allowed, provided that ≥ 6 months had elapsed since the last chemotherapy. Treatment dosages were: P200 mg/m2 IV over 3 hours; carboplatin at AUC 6 mg/mL minute calculated using standard formula(s)and REOLYSIN 3x1010 TCID50IV over 1 hour daily for 5 days every 21 days. Results: 32 patients (20 males) entered the study and received at least one dose of study drug. Median age was 62 years (range 37-80)and all were Caucasian. 25evaluable patients received more than one cycle of therapy and a total of 125 cycles were administered in that group (per patient mean=5, median=6, range 2-12). The 7 non-evaluable patients received 1 cycle or less. Of the 25 evaluable patients who received more than one cycle, 12 (48%)had a PR, 10(40%) had stable disease (SD), and 3 (12%) had progressive disease (PD) for overall disease control(CR + PR + SD) in 22/25 (88%). Of 21 patients with >6 months follow-up, 7 (33.3%) have PFS of at least 6 months. The most common adverse events (AEs) seen were those expected with P/C—neutropenia 17 (9=Gr 3-4) and thrombocytopenia 15 (5=Gr 3-4) and those expected with REOLYSIN—fever 6 (1=Gr 3) and fatigue 11 (4=Gr 3). The AE profile of P/C therapy did not appear to be significantly altered by the addition of REOLYSIN. The only serious adverse eventreported as unexpected and related to study therapy was reversible Gr 2 elevation of creatinine (and increased BUN) which occurred 3 weeks after Cycle 8 in a 65-year-old woman. Conclusions:REOLYSIN in combination with P/C was well-tolerated in patients with recurrent/metastatic SCClung and the response results justify further studies. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C70. Citation Format: Alain C. Mita, Athanassios Argiris, Matt Coffey, George Gill, Monica Mita. A phase 2 study of intravenous administration of REOLYSIN® (reovirus type 3 dearing) in combination with paclitaxel (P) and carboplatin (C) in patients with squamous cell carcinoma of the lung. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C70.

Abstract B55: A study of REOLYSIN in combination with gemcitabine in patients with advanced pancreatic adenocarcinoma.

Background: Pancreatic cancer (Pca) continues to have a dismal prognosis and very little progress has been made in finding new efficacious treatments. Oncolytic viruses have demonstrated cytotoxic effect in several tumor xenografts, particularly in cells with RAS pathway activation. REOLYSIN (Reovirus serotype 3) has shown extensive antitumor activity in preclinical models, as well as synergistic activity with cytotoxics including gemcitabine in various cancers. Several phase 1 and 2 clinical trials demonstrated tolerability and promising activity of REOLYSIN administered as a single agent in patients with solid tumors. Due to the high frequency of Kras pathway activation in Pca, we hypothesized that REOLYSIN may enhance the anticancer activity of chemotherapy in this tumor type. Therefore, this study was initiated to test the safety and efficacy of a combination of REOLYSIN with gemcitabine in previously untreated patients with Pca. Methods: Patients with diagnosis of chemotherapy-naive, surgically unresectable or metastatic Pca are eligible for the study. The primary objective is Clinical Benefit Rate (CBR=CR+PR+SD≥12 weeks). Secondary objectives include progression-free survival (PFS), toxicity, tolerability as well as pharmacokinetics (PK) and pharmacodynamics (PD). Patients are treated with gemcitabine at 800 mg/m2 day 1 and 8, and REOLYSIN administered IV at day 1, 2 and 8, 9. Tumor assessment is performed every 2 cycles (6 weeks). A two stage design is used for this study. In stage 1 at least 3/17 patients must achieve CBR in order to proceed to stage 2. Results: Fourteen patients were enrolled in the study and 10 are evaluable for efficacy. Age ranged from 48 to 82 years, mean 67 years. All patients except one reported symptomatic improvement. No CR were reported. Two patients have SD for ≥36 weeks and one patient continues on study with SD at 39 weeks. An additional patient had an unconfirmed PR of less than 6 weeks. Six patients had SD ≥ 12 weeks. The treatment was well tolerated with common non-hematological toxicities including grade 1 fever, chills, nausea and vomiting. Only two patients had grade 3 neutropenia lasting 1–2 days. No other grade 3 toxicities were seen. Conclusion: The endpoint for the first stage of the study (≥3 CBR in the first 17 patients) has been reached and therefore enrollment will continue. REOLYSIN in combination with gemcitabine has demonstrated clinical benefit in patients with unresectable Pca with a tolerable toxicity profile. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B55.