Purpose: To evaluate the feasibility and safety of intratumoral injection of an adenoviral vector encoding human interleukin-12 genes (Ad.IL-12) and secondarily, its biologic effect for the treatment of advanced digestive tumors. Patients and Methods: Ad.IL-12 was administered in doses ranging from 2.5 × 10¹⁰ to 3 × 10¹² viral particles, to seven cohorts of patients with advanced pancreatic, colorectal, or primary liver malignancies. Patients were thoroughly assessed for toxicity, and antitumor response was evaluated by imaging techniques, tumor biopsy, and hypersensitivity skin tests. Patients with stable disease and no serious adverse reactions were allowed to receive up to 3 monthly doses of Ad.IL-12. Results: Twenty-one patients (nine with primary liver, five with colorectal, and seven with pancreatic cancers) received a total of 44 injections. Ad.IL-12 was well tolerated, and dose-limiting toxicity was not reached. Frequent but transient adverse reactions, including fever, malaise, sweating, and lymphopenia, seemed to be related to vector injection rather than to transgene expression. No cumulative toxicity was observed. In four of 10 assessable patients, a significant increase in tumor infiltration by effector immune cells was apparent. A partial objective remission of the injected tumor mass was observed in a patient with hepatocellular carcinoma. Stable disease was observed in 29% of patients, mainly those with primary liver cancer. Conclusion: Intratumoral injection of up to 3 × 10¹² viral particles of Ad.IL-12 to patients with advanced digestive malignancies is a feasible and well-tolerated procedure that exerts only mild antitumor effects.

Radioembolization (RE)-induced liver disease (REILD) has been defined as jaundice and ascites appearing 1 to 2 months after RE in the absence of tumor progression or bile duct occlusion. Our aims were to study the incidence of REILD in a large cohort of patients and the impact of a series of changes introduced in the processes of treatment design, activity calculation, and the routine use of ursodeoxycholic acid and low-dose steroids (modified protocol). Between 2003 and 2011, 260 patients with liver tumors treated by RE were studied (standard protocol: 75, modified protocol: 185). REILD appeared only in patients with cirrhosis or in noncirrhosis patients exposed to systemic chemotherapy prior to RE. Globally, the incidence of REILD was reduced in the modified protocol group from 22.7% to 5.4% and the incidence of severe REILD from 13.3% to 2.2% ( P < 0.0001). Treatment efficacy was not jeopardized since 3-month disease control rates were virtually identical in both groups (66.7% and 67.2%, P = 0.93). Exposure to chemotherapy in the 2-month period following RE and being treated by the standard protocol were independent predictors of REILD among noncirrhosis patients. In cirrhosis, the presence of a small liver (total volume <1.5 L), an abnormal bilirubin (>1.2 mg/dL), and treatment in a selective fashion were independently associated with REILD. Conclusion : REILD is an uncommon but relevant complication that appears when liver tissue primed by cirrhosis or prior and subsequent chemotherapy is exposed to the radiation delivered by radioactive microspheres. We designed a comprehensive treatment protocol that reduces the frequency and the severity of REILD. (Hepatology 2013)

Recombinant adeno-associated viral vectors (rAAV) currently constitute a real therapeutic strategy for the sustained correction of diverse genetic conditions. Though a wealth of preclinical and clinical studies have been conducted with rAAV, the oncogenic potential of these vectors is still controversial, particularly when considering liver-directed gene therapy. Few preclinical studies and the recent discovery of incomplete wild-type AAV2 genomes integrated in human hepatocellular carcinoma biopsies have raised concerns on rAAV safety. In the present study, we have characterized the integration of both complete and partial rAAV2/5 genomes in nonhuman primate tissues and clinical liver biopsies from a trial aimed to treat acute intermittent porphyria. We applied a new multiplex linear amplification-mediated polymerase chain reaction (PCR) assay capable of detecting integration events that are originated throughout the rAAV genome. The integration rate was low both in nonhuman primates and patient's samples. Importantly, no integration clusters or events were found in genes previously reported to link rAAV integration with hepatocellular carcinoma development, thus showing the absence of genotoxicity of a systemically administered rAAV2/5 in a large animal model and in the clinical context.

To evaluate the feasibility and safety of intratumoral injection of autologous dendritic cells (DCs) transfected with an adenovirus encoding interleukin-12 genes (AFIL-12) for patients with metastatic gastrointestinal carcinomas. Secondarily, we have evaluated biologic effects and antitumoral activity. Seventeen patients with metastatic pancreatic (n = 3), colorectal (n = 5), or primary liver (n = 9) malignancies entered the study. DCs were generated from CD14+ monocytes from leukapheresis, cultured and transfected with AFIL-12 before administration. Doses from 10 × 10⁶to 50 × 10⁶cells were escalated in three cohorts of patients. Patients received up to three doses at 21-day intervals. Fifteen (88%) and 11 of 17 (65%) patients were assessable for toxicity and response, respectively. Intratumoral DC injections were mainly guided by ultrasound. Treatment was well tolerated. The most common side effects were lymphopenia, fever, and malaise. Interferon gamma and interleukin-6 serum concentrations were increased in 15 patients after each treatment, as well as peripheral blood natural killer activity in five patients. DC transfected with AFIL-12 stimulated a potent antibody response against adenoviral capsides. DC treatment induced a marked increase of infiltrating CD8+ T lymphocytes in three of 11 tumor biopsies analyzed. A partial response was observed in one patient with pancreatic carcinoma. Stable disease was observed in two patients and progression in eight patients, with two of the cases fast-progressing during treatment. Intratumoral injection of DC transfected with an adenovirus encoding interleukin-12 to patients with metastatic gastrointestinal malignancies is feasible and well tolerated. Further studies are necessary to define and increase clinical efficacy.