Fatal Meningitis in Swine after Intrathecal Administration of Adeno-associated Virus Expressing Syngeneic Interleukin-10.

Interleukin-10 (IL-10) delivered by intrathecal (i.t.) gene vectors is a candidate investigational new drug (IND) for several chronic neurological disorders such as neuropathic pain. We performed a preclinical safety study of IL-10. A syngeneic large animal model was used delivering porcine IL-10 (pIL-10) to the i.t. space in swine by adeno-associated virus serotype 8 (AAV8), a gene vector that was previously found to be nontoxic in the i.t. space. Unexpectedly, animals became ill, developing ataxia, seizures, and an inability to feed and drink, and required euthanasia. Necropsy demonstrated lymphocytic meningitis without evidence of infection in the presence of normal laboratory findings for body fluids and normal histopathology of peripheral organs. Results were replicated in a second animal cohort by a team of independent experimenters. An extensive infectious disease and neuropathology workup consisting of comprehensive testing of tissues and body fluids in a specialized research veterinary pathology environment did not identify a pathogen. These observations raise the concern that i.t. IL-10 therapy may not be benign, that previously used xenogeneic models testing the human homolog of IL-10 may not have been sensitive enough to detect toxicity, and that additional preclinical studies may be needed before clinical testing of IL-10 can be considered.

Clinical Course of Oxaliplatin-Induced Neuropathy: Results From the Randomized Phase III Trial N08CB (Alliance).

PURPOSE: Given that the clinical course of oxaliplatin-induced neuropathy is not well defined, the current study was performed to better understand clinical parameters associated with its presentation. METHODS: Acute and chronic neuropathy was evaluated in patients receiving adjuvant FOLFOX (fluorouracil, leucovorin, and oxaliplatin) on study N08CB (North Central Cancer Treatment Group, Alliance). Acute neuropathy was assessed by having patients complete daily questionnaires for 6 days with each cycle of FOLFOX. Before each dose of FOLFOX and as long as 18 months after chemotherapy cessation, chronic neurotoxicity was assessed with use of the 20-item, European Organisation for Research and Treatment of Cancer quality-of-life questionnaire for patients with chemotherapy-induced peripheral neuropathy. RESULTS: Three hundred eight (89%) of the 346 patients had at least one symptom of acute neuropathy with the first cycle of FOLFOX; these symptoms included sensitivity to touching cold items (71%), sensitivity to swallowing cold items (71%), throat discomfort (63%), or muscle cramps (42%). Acute symptoms peaked at day 3 and improved, although they did not always resolve completely between treatments. These symptoms were about twice as severe in cycles 2 through 12 as they were in cycle 1. For chronic neurotoxicity, tingling was the most severe symptom, followed by numbness and then pain. During chemotherapy, symptoms in the hands were more prominent than they were in the feet; by 18 months, symptoms were more severe in the feet than they were in the hands. Patients with more severe acute neuropathy during the first cycle of therapy experienced more chronic sensory neurotoxicity (P < .0001). CONCLUSION: Acute oxaliplatin-induced neuropathy symptoms do not always completely resolve between treatment cycles and are only half as severe on the first cycle as compared with subsequent cycles. There is a correlation between the severities of acute and chronic neuropathies.

Preclinical toxicity evaluation of AAV for pain: evidence from human AAV studies and from the pharmacology of analgesic drugs.

Gene therapy with adeno-associated virus (AAV) has advanced in the last few years from promising results in animal models to >100 clinical trials (reported or under way). While vector availability was a substantial hurdle a decade ago, innovative new production methods now routinely match the scale of AAV doses required for clinical testing. These advances may become relevant to translational research in the chronic pain field. AAV for pain targeting the peripheral nervous system was proven to be efficacious in rodent models several years ago, but has not yet been tested in humans. The present review addresses the steps needed for translation of AAV for pain from the bench to the bedside focusing on pre-clinical toxicology. We break the potential toxicities into three conceptual categories of risk: First, risks related to the delivery procedure used to administer the vector. Second, risks related to AAV biology, i.e., effects of the vector itself that may occur independently of the transgene. Third, risks related to the effects of the therapeutic transgene. To identify potential toxicities, we consulted the existing evidence from AAV gene therapy for other nervous system disorders (animal toxicology and human studies) and from the clinical pharmacology of conventional analgesic drugs. Thereby, we identified required preclinical studies and charted a hypothetical path towards a future phase I/II clinical trial in the oncology-palliative care setting.

Therapy for unresectable hepatocellular carcinoma: review of the randomized clinical trials-II: systemic and local non-embolization-based therapies in unresectable and advanced hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is not only common, but often presents at a stage when potentially curative therapies are not feasible. Although hepatic artery chemoembolization likely confers survival benefit in unresectable HCC, the associated toxicities are substantial and warrant investigation of more efficacious and safe therapies. Many patients who present with unresectable HCC are not chemoembolization candidates, either because of extensive disease or severely impaired hepatic function. We reviewed 44 randomized trials investigating non-embolization-based therapies in unresectable HCC. Hepatic artery infusion of [I]lipiodol appears safe; initial studies suggest a survival benefit and efficacy comparable to more toxic embolization-based therapies. Some cytotoxic chemotherapy may confer a modest survival benefit in advanced HCC (including oral fluoropyrimidines, and hepatic arterial or i.v. cisplatin and doxorubicin). Tamoxifen does not confer survival benefit, either in advanced or limited HCC. Other therapies warranting further study include interferon (in optimally cytoreduced HCC), megestrol in patients with variant estrogen receptors, octreotide and pravastatin. More adequately powered, rigorously conducted studies will hopefully identify useful chemo-, radio-, immuno-, embolization-based and biologically targeted therapies during the next decade.