A multicenter pilot study of a bronchial valve for the treatment of severe emphysema.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) affects millions of people and has limited treatment options. Surgical treatments for severe COPD with emphysema are effective for highly selected patients. A minimally invasive method for treating emphysema could decrease morbidity and increase acceptance by patients. OBJECTIVE: To study the safety and effectiveness of the IBV(R) Valve for the treatment of severe emphysema. METHODS: A multicenter study treated 91 patients with severe obstruction, hyperinflation and upper lobe (UL)-predominant emphysema with 609 bronchial valves placed bilaterally into ULs. RESULTS: Valves were placed in desired airways with 99.7% technical success and no migration or erosion. There were no procedure-related deaths and 30-day morbidity and mortality were 5.5 and 1.1%, respectively. Pneumothorax was the most frequent serious device-related complication and primarily occurred when all segments of a lobe, especially the left UL, were occluded. Highly significant health-related quality of life (HRQL) improvement (-8.2 +/- 16.2, mean +/- SD change at 6 months) was observed. HRQL improvement was associated with a decreased volume (mean -294 +/- 427 ml, p = 0.007) in the treated lobes without visible atelectasis. FEV(1), exercise tests, and total lung volume were not changed but there was a proportional shift, a redirection of inspired volume to the untreated lobes. Combined with perfusion scan changes, this suggests that there is improved ventilation and perfusion matching in non-UL lung parenchyma. CONCLUSION: Bronchial valve treatment of emphysema has multiple mechanisms of action and acceptable safety, and significantly improves quality of life for the majority of patients.

Eradication of intraperitoneal and distant tumor by adenovirus-mediated interferon-beta gene therapy is attributable to induction of systemic immunity.

Malignant mesothelioma remains an incurable disease for which immune-modulatory therapies, such as exogenous cytokines, have shown some promise. One such cytokine, IFN-beta, has potent antiproliferative and immunostimulatory activity in vitro, but its in vivo use has been limited by toxicity. We thus conducted studies evaluating intracavitary delivery of a replication-deficient adenoviral (Ad) vector encoding for the murine IFN-beta gene (Ad.muIFN-beta) in mouse models of malignant mesothelioma. In contrast to multiple injections of recombinant protein, a single i.p. injection of Ad.muIFN-beta into animals with established tumors elicited remarkable antitumor activity leading to long-term survival in >90% of animals bearing either AB12 or AC29 i.p. mesotheliomas. A control adenovirus vector had minimal antitumor effect in vivo. Significant therapeutic effects were also seen in animals treated with large tumor burdens. Importantly, treatment of i.p. tumor also led to reduction of growth in tumors established at a distant site (flank). A number of experiments suggested that these effects were attributable to an acquired CD8(+) T-cell-mediated response including: (a) the induction of long-lasting antitumor immunity; (b) loss of efficacy of Ad.muIFN-beta in tumor-bearing, immune-deficient (SCID, SCID/beige) mice; (c) detection of high levels of specific antitumor cytolytic activity from unstimulated splenocytes harvested from Ad.muIFN-beta-treated animals that was abolished by CD8(+) T-cell depletion; and (d) abrogation of antitumor effects of Ad.muIFN-beta in tumor-bearing CD8(+) T-cell-depleted animals. These data show that intracavitary IFN-beta gene therapy using an adenoviral vector provides strong CD8(+) T-cell-mediated antitumor effects in murine models of mesothelioma and suggest that this may be a promising strategy for the treatment of localized tumors such as mesothelioma or ovarian cancer in humans.

Use of an implantable pleural catheter for trapped lung syndrome in patients with malignant pleural effusion.

STUDY OBJECTIVES: We describe a series of patients with symptomatic, refractory malignant pleural effusion (MPE) and underlying trapped lung syndrome who underwent placement of a small-bore, flexible indwelling pleural catheter for home drainage of recurrent MPE. DESIGN: The medical records of 11 consecutive patients who underwent pleural catheter placement for MPE with trapped lung syndrome were reviewed retrospectively. SETTING: Patients were evaluated and followed up in the Pulmonary Outpatient Practice at the Hospital of the University of Pennsylvania. PATIENTS: Nine men and two women with underlying malignancies including lung cancer, lymphoma, and mesothelioma underwent pleural catheter placement. INTERVENTIONS: Thirteen pleural catheters were placed in 11 patients, all under local anesthesia. Patients received detailed instructions for drainage and catheter care. They were reevaluated weekly for the first 2 weeks, and then as clinically indicated. Patients typically performed pleural drainage at home up to 1,000 mL two or three times weekly. MEASUREMENTS AND RESULTS: All patients reported symptomatic benefit, defined as improved dyspnea and exercise tolerance, except for one patient. In 10 patients, the pleural catheters remained in place until death, for 15 to 234 days. The mean length of placement was 115 days. One patient required revision after catheter occlusion. Other complications included catheter infection, localized skin breakdown, and possible cellulitis. CONCLUSION: We have described a series of patients with MPE and trapped lung syndrome for whom placement of a permanent pleural catheter provided a convenient, effective alternative to the procedures currently in use. Our patients reported good symptomatic relief following catheter placement with few major complications.

Bronchial anastomotic stricutre caused by ossification of an intercostal muscle flap.

We report a case of heterotopic ossification of a pedicled intercostal muscle flap that had been wrapped circumferentially around a bronchial sleeve anastomosis. This ossification caused severe bronchial stenosis and recurrent pneumonias. Stent insertion failed, and the patient ultimately required completion pneumonectomy. We recommended that caution be used when wrapping intercostal muscle around any important lumen.

A pilot study of systemic corticosteroid administration in conjunction with intrapleural adenoviral vector administration in patients with malignant pleural mesothelioma.

One of the primary limitations of adenoviral (Ad) -mediated gene therapy is the generation of anti-Ad inflammatory responses that can induce clinical toxicity and impair gene transfer efficacy. The effects of immunosuppression on these inflammatory responses, transgene expression, and toxicity have not yet been systematically examined in humans undergoing Ad-based gene therapy trials. We therefore conducted a pilot study investigating the use of systemic corticosteroids to mitigate antivector immune responses. In a previous phase I clinical trial, we demonstrated that Ad-mediated intrapleural delivery of the herpes simplex virus thymidine kinase gene (HSVtk) to patients with mesothelioma resulted in significant, but relatively superficial, HSVtk gene transfer and marked anti-Ad humoral and cellular immune responses. When a similar group of patients was treated with Ad.HSVtk and a brief course of corticosteroids, decreased clinical inflammatory responses were seen, but there was no demonstrable inhibition of anti -Ad antibody production or Ad-induced peripheral blood mononuclear cell activation. Corticosteroid administration also had no apparent effect on the presence of intratumoral gene transfer. Although limited by the small numbers of patients studied, our data suggest that systemic administration of steroids in the context of Ad-based gene delivery may limit acute clinical toxicity, but may not inhibit cellular and humoral responses to Ad vectors.

Advances in the treatment of malignant pleural mesothelioma.

Malignant pleural mesothelioma is a neoplasm that is commonly fatal and for which there are no widely accepted curative approaches. Mesothelioma is unresponsive to most chemotherapy and radiotherapy regimens, and it typically recurs even after the most aggressive attempts at surgical resection. Multimodality approaches have been of some benefit in prolonging survival of very highly selected subgroups of patients, but they have had a relatively small impact on the majority of the patients diagnosed with this disease. As the incidence of pleural mesothelioma peaks in the United States and Europe over the next 10 to 20 years, new therapeutic measures will be necessary. This review will discuss the roles of chemotherapy, radiotherapy, surgery, and combined modality approaches in the treatment of pleural mesothelioma, as well as scientific advances made in the past decade that have led to the development of experimental techniques, such as photodynamic therapy, immunotherapy, and gene therapy, that are currently undergoing human clinical trials. These promising new avenues may modify the therapeutic nihilism that is rampant among clinicians dealing with mesothelioma.

Impact of preexisting and induced humoral and cellular immune responses in an adenovirus-based gene therapy phase I clinical trial for localized mesothelioma.

Little is known about the immune responses induced by recombinant adenoviral (Ad) vectors in humans. The humoral and cellular immune responses were therefore analyzed in 21 patients with localized malignancy (mesothelioma), who received intrapleurally high doses of a replication-defective Ad5 vector carrying a suicide gene. Eight of 21 patients had pretreatment titers of neutralizing antibodies (NAb) to Ad at > or =1:100. Peripheral blood mononuclear cells (PBMCs) proliferated in response to adenoviral 5 structural proteins before treatment in 17 of 21 patients. Preexisting humoral and cellular immunity did not preclude gene transfer. Vector instillation induced high titers of nonneutralizing and neutralizing anti-Ad antibody (4- to 341-fold increase in 18 of 20 patients) in a dose-dependent manner. Three patients generated antibodies to the transgene, herpes simplex virus thymidine kinase. Ad5-specific proliferation of PBMCs increased significantly (>3-fold) after vector administration in 12 of 21 patients in a dose-dependent manner. Thus, replication-defective Ad5 administered intrapleurally induced significant humoral and cellular immune responses that induced no obvious adverse clinical sequelae.

Gene therapy for malignant pleural mesothelioma.

Malignant mesothelioma (MM) is a fatal malignancy refractory to all forms of standard anticancer therapy. This article reports the results of a phase I clinical trial assessing the safety of intrapleural delivery and efficacy of intratumoral gene transfer of recombinant adenovirus (rAd) containing herpes simplex virus thymidine kinase (HSVtk) gene into the pleural space of patients with MM, followed by systematic treatment with the antiviral drug ganciclovir (GCV) for 14 days. AD.RSVtk/GCV gene therapy proved to be well tolerated, with evidence of significant gene transfer particularly at high vector doses and with elimination of preliminary biopsy. Ongoing gene therapy trials for mesothelioma at two other centers, focusing on immunostimulation and using suicide gene therapy as a tumor vaccine, are also reviewed in this article.

Adenovirus-mediated herpes simplex virus thymidine kinase/ganciclovir gene therapy in patients with localized malignancy: results of a phase I clinical trial in malignant mesothelioma.

Malignant pleural mesothelioma is a fatal neoplasm that is unresponsive to standard modalities of cancer therapy. We conducted a phase I dose-escalation clinical trial of adenoviral (Ad)-mediated intrapleural herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) gene therapy in patients with mesothelioma as a model for treatment of a localized malignancy. The goals of this phase I trial were to assess the safety, toxicity, and maximally tolerated dose of intrapleural Ad.HSVtk, to examine patient inflammatory response to the viral vector, and to evaluate the efficiency of intratumoral gene transfer. Twenty-one previously untreated patients were enrolled in this single-arm, dose-escalation study with viral doses ranging from 1 x 10(9) plaque-forming units (pfu) to 1 x 10(12) pfu. A replication-incompetent recombinant adenoviral vector containing the HSVtk gene under control of the Rous sarcoma virus (RSV) promoter-enhancer was introduced into the pleural cavity of patients with malignant mesothelioma followed by 2 weeks of systemic therapy with GCV at a dose of 5 mg/kg twice a day. The initial 15 patients underwent thoracoscopic pleural biopsy prior to, and 3 days after, vector delivery. The last six patients underwent only the post-vector instillation biopsy. Dose-limiting toxicity was not reached. Side effects were minimal and included fever, anemia, transient liver enzyme elevations, and bullous skin eruptions, as well as a temporary systemic inflammatory response in those receiving the highest dose. Strong intrapleural and intratumoral immune responses were generated. Using RNA PCR, in situ hybridization, immunohistochemistry, and immunoblotting, HSVtk gene transfer was documented in 11 of 20 evaluable patients in a dose-related fashion. This study demonstrates that intrapleural administration of an adenoviral vector containing the HSVtk gene is well tolerated and results in detectable gene transfer when delivered at high doses. Further development of therapeutic trials for treatment of localized malignancy using this vector is thus warranted.

Use of a "replication-restricted" herpes virus to treat experimental human malignant mesothelioma.

Modified, nonneurovirulent herpes simplex viruses (HSVs) have shown promise in the treatment of brain tumors. However, HSV-1 can infect and lyse a wide range of cell types. In this report, we show that HSV-1716, a mutant lacking both copies of the gene coding ICP-34.5, can effectively treat a localized i.p. malignancy. Human malignant mesothelioma cells supported the growth of HSV-1716 and were efficiently lysed in vitro. i.p. injection of HSV-1716 into animals with established tumor nodules reduced tumor burden and significantly prolonged survival in an animal model of non-central nervous system-localized human malignancy without dissemination or persistence after i.p. injection into SCID mice bearing human tumors. These findings suggest that this virus may be efficacious and safe for use in localized human malignancies of nonneuronal origin such as malignant mesothelioma.

Safety of intrapleurally administered recombinant adenovirus carrying herpes simplex thymidine kinase DNA followed by ganciclovir therapy in nonhuman primates.

Preclinical safety and toxicity studies of intrapleural administration of recombinant adenovirus carrying the herpes simplex thymidine kinase gene (H5.010RSVtk) were performed. Previously reported experimental evidence has demonstrated the efficacy of this approach in animal models of a localized thoracic cancer, malignant mesothelioma. H5.010RSVtk was delivered at high dose (10(12) pfu) into the pleural cavity of three non-human primates followed by systemic administration of ganciclovir. No clinical toxicity was noted. Although an inflammatory reaction observable by microscopy was noted in the serosal spaces of the chest cavity, these changes were reversible and were not associated with radiographic sequelae. Extrathoracic viral dissemination was minimal and detectable only by sensitive polymerase chain reaction techniques. This low level of viral dissemination was not associated with detectable clinical, biochemical, or pathologic abnormalities.

The role of immunosuppression in the efficacy of cancer gene therapy using adenovirus transfer of the herpes simplex thymidine kinase gene.

OBJECTIVE: To determine whether the immune system limits or improves the therapeutic efficacy of an adenovirus vector expressing the herpes simplex thymidine kinase (HSVtk) gene in a subcutaneous tumor model. BACKGROUND DATA: Enhanced immune reactions against tumors may be therapeutically useful. However, recent studies with adenoviral vectors show that immune responses limit the efficacy and persistence of gene expression. The effect of the immune response on cancer gene therapy with HSVtk gene delivery by an adenovirus vector followed by treatment with ganciclovir is unclear. METHODS: After adenoviral transduction of a Fischer rat syngeneic mesothelioma cell line with the HSVtk gene in vitro, subcutaneous flank tumors were established. The ability of the HSVtk/ganciclovir system to inhibit tumor growth was compared among normal Fischer rats, immunodeficient nude rats, and Fischer rats immunosuppressed with cyclosporin. RESULTS: HSVtk/ganciclovir therapy was more effective in nude rats and immunosuppressed Fischer rats than in immunocompetent Fischer rats. CONCLUSION: These results indicate that the immune response against adenovirally transduced cells limits the efficacy of the HSVtk/ganciclovir system and that immunosuppression appears to be a useful adjunct. These findings have important implications for clinical trials using currently available adenovirus vectors as well as for future vector design.