Toxicity Profile of eBAT, a Bispecific Ligand-Targeted Toxin Directed to EGFR and uPAR, in Mice and a Clinical Dog Model.

EGFR-targeted therapies are efficacious, but toxicity is common and can be severe. Urokinase type plasminogen activator receptor (uPAR)-targeted drugs are only emerging, so neither their efficacy nor toxicity is fully established. Recombinant eBAT was created by combining cytokines EGF and uPA on the same single-chain molecule with truncated Pseudomonas toxin. Its purpose was to simultaneously target tumors and their vasculature in the tumor microenvironment. In prior studies on mice and dogs, the drug proved efficacious. Here, we report the safety of eBAT in normal wildtype, uPAR knockout, and immunoreplete and immunodeficient tumor-bearing mice, as well as in dogs with spontaneous sarcoma that more closely mirror human cancer onset. In immunocompetent mice, tumor-bearing mice, uPAR knockout mice, and mice receiving species-optimized eBAT, toxicities were mild and self-limiting. Likewise, in dogs with life-threatening sarcoma given dosages found to be biologically active, eBAT was well tolerated. In mice receiving higher doses, eBAT was associated with dose-dependent evidence of liver injury, including portal biliary hyperplasia, oval cell proliferation, lymphoplasmacytic inflammation, periportal hepatocellular microvesicular change, hemorrhage, necrosis, and apoptosis. The results support continuing the clinical development of eBAT as a therapeutic agent for individuals with sarcoma and other cancers.

Nine-axis inertial measurement unit output discriminates activities of varying intensity in the dog.

OBJECTIVE: To explore relationships between 9-axis inertial measurement unit (IMU) output and activities of varying intensity in dogs of various sizes. ANIMALS: 20 healthy, agility course-trained dogs of various ages and sizes. PROCEDURES: Height, weight, body condition score, age, length from IMU to the ischium, and height of IMU to the floor were recorded. Dogs performed a series of activities (rest, walk, trot, and agility course) while wearing the IMU device. IMU and video output were reviewed by independent investigators. Correlations and multiple regression models were used to explore relationships between independent variables and IMU output. RESULTS: Calibration demonstrated excellent correlation and concordance between IMUs (intraclass correlation > 0.9) and that the IMUs reliably measured a known acceleration (gravity at rest). Resultant vector magnitude {sqrt[(x^2) + (y^2) + (z^2)]} normalized to body size was calculated from the data. IMU output clearly discriminates between activities of varying intensity in the dog. CLINICAL RELEVANCE: The inability to accurately measure chronic pain is a barrier to the development of new, or critical evaluation of, therapeutics. Activity monitors (AM) may be the ideal diagnostic target since they are small and provide objective data that can be collected while the pet remains in its natural environment. These results demonstrate the concurrent and predictive validity of the IMU tested. Our long-range goal is to validate an open-source algorithm for the IMU so activity in a pet's natural environment can be used as an outcome measure in future studies.

Neoadjuvant systemic oncolytic vesicular stomatitis virus is safe and may enhance long-term survivorship in dogs with naturally occurring osteosarcoma.

Osteosarcoma is a devastating bone cancer that disproportionally afflicts children, adolescents, and young adults. Standard therapy includes surgical tumor resection combined with multiagent chemotherapy, but many patients still suffer from metastatic disease progression. Neoadjuvant systemic oncolytic virus (OV) therapy has the potential to improve clinical outcomes by targeting primary and metastatic tumor sites and inducing durable antitumor immune responses. Here we describe the first evaluation of neoadjuvant systemic therapy with a clinical-stage recombinant oncolytic vesicular stomatitis virus (VSV), VSV-IFNß-NIS, in naturally occurring cancer, specifically appendicular osteosarcoma in companion dogs. Canine osteosarcoma has a similar natural disease history as its human counterpart. VSV-IFNß-NIS was administered prior to standard of care surgical resection, permitting microscopic and genomic analysis of tumors. Treatment was well-tolerated and a "tail" of long-term survivors (∼35%) was apparent in the VSV-treated group, a greater proportion than observed in two contemporary control cohorts. An increase in tumor inflammation was observed in VSV-treated tumors and RNA-seq analysis showed that all the long-term responders had increased expression of a T cell anchored immune gene cluster. We conclude that neoadjuvant VSV-IFNß-NIS is safe and may increase long-term survivorship in dogs with naturally occurring osteosarcoma, particularly those that exhibit pre-existing antitumor immunity.

Neoadjuvant systemic oncolytic vesicular stomatitis virus is safe and may enhance long-term survivorship in dogs with naturally occurring osteosarcoma.

Osteosarcoma is a devastating bone cancer that disproportionally afflicts children, adolescents, and young adults. Standard therapy includes surgical tumor resection combined with multiagent chemotherapy, but many patients still suffer from metastatic disease progression. Neoadjuvant systemic oncolytic virus (OV) therapy has the potential to improve clinical outcomes by targeting primary and metastatic tumor sites and inducing durable antitumor immune responses. Here we described the first evaluation of neoadjuvant systemic therapy with a clinical-stage recombinant oncolytic Vesicular stomatitis virus (VSV), VSV-IFNß-NIS, in naturally occurring cancer, specifically appendicular osteosarcoma in companion dogs. Canine osteosarcoma has a similar natural disease history as its human counterpart. VSV-IFNß-NIS was administered prior to standard of care surgical resection, permitting microscopic and genomic analysis of tumors. Treatment was well-tolerated and a 'tail' of long-term survivors (~35%) was apparent in the VSV-treated group, a greater proportion than observed in two contemporary control cohorts. An increase in tumor inflammation was observed in VSV-treated tumors and RNAseq analysis showed that all the long-term responders had increased expression of a T-cell anchored immune gene cluster. We conclude that neoadjuvant VSV-IFNß-NIS is safe and may increase long-term survivorship in dogs with naturally occurring osteosarcoma, particularly those that exhibit pre-existing antitumor immunity.