Henrik S. Rasmussen

Regional Angiogenesis With Vascular Endothelial Growth Factor in Peripheral Arterial Disease A Phase II Randomized, Double-Blind, Controlled Study of Adenoviral Delivery of Vascular Endothelial Growth Factor 121 in Patients With Disabling Intermittent Claudication

Background—“Therapeutic angiogenesis” seeks to improve perfusion by the growth of new blood vessels. The Regional Angiogenesis with Vascular Endothelial growth factor (RAVE) trial is the first major randomized study of adenoviral vascular endothelial growth factor (VEGF) gene transfer for the treatment of peripheral artery disease (PAD). Methods and Results—This phase 2, double-blind, placebo-controlled study was designed to test the efficacy and safety of intramuscular delivery of AdVEGF121, a replication-deficient adenovirus encoding the 121-amino-acid isoform of vascular endothelial growth factor, to the lower extremities of subjects with unilateral PAD. In all, 105 subjects with unilateral exercise-limiting intermittent claudication during 2 qualifying treadmill tests, with peak walking time (PWT) between 1 to 10 minutes, were stratified on the basis of diabetic status and randomized to low-dose (4×109 PU) AdVEGF121, high-dose (4×1010 PU) AdVEGF121, or placebo, administered as 20 intramuscular injections to the index leg in a single session. The primary efficacy end point, change in PWT (&Dgr;PWT) at 12 weeks, did not differ between the placebo (1.8±3.2 minutes), low-dose (1.6±1.9 minutes), and high-dose (1.5±3.1 minutes) groups. Secondary measures, including &Dgr;PWT, ankle-brachial index, claudication onset time, and quality-of-life measures (SF-36 and Walking Impairment Questionnaire), were also similar among groups at 12 and 26 weeks. AdVEGF121 administration was associated with increased peripheral edema. Conclusions—A single unilateral intramuscular administration of AdVEGF121 was not associated with improved exercise performance or quality of life in this study. This study does not support local delivery of single-dose VEGF121 as a treatment strategy in patients with unilateral PAD.

TNFerade Biologic, an Adenovector With a Radiation-Inducible Promoter, Carrying the Human Tumor Necrosis Factor Alpha Gene: A Phase I Study in Patients With Solid Tumors

PURPOSE TNFerade is a replication deficient adenovector that expresses human tumor necrosis factor alpha under control of the radiation-inducible Egr-1 promoter. The goals of this study were to determine the safety and toxicity of TNFerade in combination with radiation therapy. PATIENTS AND METHODS TNFerade was administered by intratumoral administration, weekly for 6 weeks with concomitant radiation (30 to 70 Gy). Seven dose levels were studied (4 x 10(7) particle units [pu] to 4 x 10(11) pu) in patients with solid tumors being treated with radiation. RESULTS Thirty-six patients were assessable for toxicity and 30 for tumor response. Most frequent TNFerade-related toxicities were fever (22%), injection site pain (19%), and chills (19%). No dose-limiting toxicities were observed. Overall, 21 of 30 patients (70%) demonstrated objective tumor response (five complete responses, nine partial responses, and seven minimal responses). In four of five patients with synchronous lesions, a differential response between lesions treated with TNFerade + radiation compared with radiation only was observed. CONCLUSION This is the first human study with TNFerade and radiation. The integrated treatment was well tolerated in patients with predominantly prior treatment-refractory solid tumors. Controlled prospective clinical trials have been initiated to more fully define the therapeutic contribution of TNFerade.

Safety of Local Delivery of Low- and Intermediate-Dose Adenovirus Gene Transfer Vectors to Individuals with a Spectrum of Morbid Conditions

To help define the safety profile of the use of adenovirus (Ad) gene transfer vectors in humans, this report summarizes our experience since April 1993 of the local administration of E1(-)/E3(-) Ad vectors to humans using low (<10(9) particle units) or intermediate (10(9)-10(11) particle units) doses. Included in the study are 90 individuals and 12 controls, with diverse comorbid conditions, including cystic fibrosis, colon cancer metastatic to liver, severe coronary artery disease, and peripheral vascular disease, as well as normals. These individuals received 140 different administrations of vector, with up to seven administrations to a single individual. The vectors used include three different transgenes (human cystic fibrosis transmembrane conductance regulator cDNA, E. coli cytosine deaminase gene, and the human vascular endothelial growth factor 121 cDNA) administered by six different routes (nasal epithelium, bronchial epithelium, percutaneous to solid tumor, intradermal, epicardial injection of the myocardium, and skeletal muscle). The total population was followed for 130.4 patient-years. The study assesses adverse events, common laboratory tests, and long-term follow-up, including incidence of death or development of malignancy. The total group incidence of major adverse events linked to an Ad vector was 0.7%. There were no deaths attributable to the Ad vectors per se, and the incidence of malignancy was within that expected for the population. Overall, the observations are consistent with the concept that local administration of low and intermediate doses of Ad vectors appears to be well tolerated.

Marimastat in patients with advanced pancreatic cancer: A dose-finding study

Patients with solid tumors, including carcinoma of the pancreas, express high levels of matrix metalloproteinases (MMP), and these enzymes are believed to be important for the growth, spread, and dissemination of most solid malignant tumors. Marimastat is the first orally available MMP inhibitor (MMPI) to be tested in humans and has been shown to inhibit the spread and growth of pancreatic cancer in animal models. The purpose of the present study was to define the toxicities, safety, and tolerance of various doses of marimastat and also to get an early indication of potential biologic activity in patients with advanced pancreatic cancer. The authors prospectively studied 64 patients with advanced carcinoma of the pancreas in whom standard treatments had failed. Eligible patients had a progressive rise in CA 19/9 levels of >25% over the 4-week period preceding their entry into the study. Patients were studied in groups of 8 to 10, with each group receiving escalating dosages ranging from 5 mg twice daily to 75 mg twice daily and 10 to 25 mg daily. Patients were considered for long-term (beyond 4 weeks) continuation treatment if clinical benefit, in the view of the investigator, was derived. Study endpoints were safety, tolerance, and changes in the rate of rise of CA 19/9, which were used as surrogate markers for disease progression. Marimastat was well tolerated. Musculoskeletal pain, stiffness, and tenderness emerged as dose-limiting toxicity. No other dose-related toxicities were observed. A reduced rate of rise of CA 19/9 was observed at dose levels of 5, 10, and 25 mg twice daily. The overall median survival was 160 days, with a 1-year survival of 21%. Marimastat was associated with an acceptable toxicity profile, and these preliminary data suggest that long-term oral administration is feasible and safe. Doses of 5, 10, and 25 mg twice daily were identified as the optimal doses to be tested in larger randomized studies.

A Phase I Trial of TNFerade Biologic in Patients with Soft Tissue Sarcoma in the Extremities

Purpose: TNFerade is a second-generation replication-deficient adenovector carrying a transgene encoding human tumor necrosis factor α under control of a radiation- induced promoter. The objective of this study was to assess the tolerance of combining TNFerade and radiation therapy in patients with soft tissue sarcomas of the extremity. Experimental Design: TNFerade was administered in combination with single-daily fractionated radiation therapy in 14 patients with soft tissue sarcoma of the extremities. Three escalating dose levels of TNFerade (4 × 109 −4 × 1011 particle units) were planned, given in 1 log increments by intratumoral injections, twice weekly during week 1 and once weekly during weeks 2–5 of radiation therapy. Results: TNFerade was well tolerated with no dose-limiting toxicities noted. Grade 1–2 chills (50.0%), fever (43.0%), fatigue (36.0%), and flu-like symptoms (21.0%) were the most common side effects. Serum-tumor necrosis factor α levels were low in all of the patients (<15 pg/mL). No patients had virus-detected blood, sputum, or urine cultures. Of the 13 evaluable patients, 11 received TNFerade preoperatively, and 2 received the treatment for palliation. Eleven patients (85%) showed objective or pathological tumor responses (2 complete and 9 partial), and 1 had stable disease. Partial responses were achieved despite some of these tumors being very large (up to 675 cm2). Of the 11 patients who underwent surgery, 10 (91%) showed a pathological complete response/partial response. Conclusion: TNFerade + radiation therapy was well tolerated in the treatment of patients with soft-tissue sarcoma of the extremity. The high number of objective responses observed warrants additional studies of this approach in a larger controlled prospective trial.

TNFerade Biologic: Preclinical toxicology of a novel adenovector with a radiation-inducible promoter, carrying the human tumor necrosis factor alpha gene

TNFerade Biologic (TNFerade) is a second-generation (E1-, E3-, and E4-deleted) replication-deficient adenovector carrying the transgene encoding for human tumor necrosis factor alpha (TNFα), regulated by the radiation-sensitive promoter Early Growth Response (Egr-1). We hypothesized that intratumoral injection of TNFerade followed by radiation would result in potentially therapeutic levels of TNFα with minimal toxicity. Three preclinical studies were conducted, the purpose of which was to characterize the toxicity and pharmacokinetics of TNFerade in conjunction with radiation in nude as well as immune-competent (Balb/c) mice. A total of 80 mice in the nude mouse toxicology study, all bearing human squamous cell carcinoma xenografts, 120 mice in the Balb/c study, and 33 nude mice in the pharmacokinetic study were used. Doses ranging from 4×109 to 4×1010 particle units (pu) (4×1011 pu in the Balb/c study) were explored, with and without radiation. In the nude mice studies, TNFerade was injected intratumorally, whereas in the Balb/c study, TNFerade was administered by subcutaneous injection. TNFerade was well tolerated. In the nude mice studies, no significant toxicity occurred in any dose group. In the Balb/c study, 6/40 mice at the top dose (4×1011 pu) were sacrificed in moribund condition (5/20 in the TNFerade+radiation group, 1/20 in the TNFerade alone group). Necropsy showed local necrosis and ulceration at the site of the injection. No deaths or significant toxicity were observed at the lower dose levels (4×109 and 4×1010 pu), indicating a large safety margin for initial studies in humans. The pharmacokinetic study demonstrated high sustained levels of TNFα in the tumor homogenate with no “spillover” to plasma, where TNFα levels were below the level of detection. Radiation increased intratumoral levels of TNFα by a factor of 12 (from 0.998 to 11.55 ng/g). In conclusion, a gene therapy approach with TNFerade, in combination with radiation, represents a potential way to utilize the potent anticancer activity of TNFα without systemic toxicity.

Radiation-induced tumour necrosis factor-α expression: clinical application of transcriptional and physical targeting of gene therapy

Promising data are emerging on a new anticancer agent, Ad.EGR-TNF, an adenoviral vector, which contains radio-inducible DNA sequences from the early growth response (EGR1) gene promoter and cDNA for the gene encoding human tumour necrosis factor-alpha. Ad.EGR-TNF combines the well-documented broad-spectrum anticancer activity of TNFalpha with the proven clinical usefulness of radiotherapy. Systemic delivery of the TNFalpha protein has had limited success clinically because of severe dose-limiting toxic effects. This limitation has been overcome by the use of a gene delivery approach, combined with a radiation-inducible promoter to express the TNFalpha protein in the irradiated tumour tissue. Preclinical and early phase I clinical testing indicates that effective concentrations of TNFalpha can be delivered to the tumour site without significant systemic exposure or toxic effects. The combination of radiation and TNFalpha gene delivery has produced striking antitumour effects in model systems in animals. In the clinical setting, potent anticancer activity has been observed with a high rate of complete and partial objective tumour responses. A novel mechanism of destruction of the tumour vasculature seems to be central to this distinct antitumour activity. This review summarises the rationale, mechanistic basis, preclinical data, and preliminary clinical findings for this new treatment model.

Efficacy and safety of a new selective class III antiarrhythmic agent dofetilide in paroxysmal atrial fibrillation or atrial flutter

that regional LV dysfunction is not responsible for this nonspecificity. Our results differ from those of Breithardt et al,4 who detected late potentials in only 9% of patients with normal wall motion compared with 46% of patients with regional akinesia or dyskinesia. However, the recording methodology and semiqualitative criteria for diagnosing late potentials in their study differed markedly from those currently used by most investigators2,3 and used in our report’. In addition, the results differ primarily in the higher frequency of late potentials recorded in our control group, which also exceeds the frequency of an abnormal SAECG in normal subjects reported previously in several other studies.2,5,6 However, our “normal” patients had undergone cardiac catheterization and were much older than the normal subjects in those studies, which consisted of nurses and medical residents2 or other healthy volunteers who had not undergone cardiac catheterization.5,6 Increasing age has been found recently to independently increase the incidence of late potentials,7 and probably accounts for the frequency of late potentials in our control group. This finding of a reduced positive predictive value of the SAECG in older patients has important implic;ations for the prospective value of this test, because the question of susceptibility to VT is far more likely to be raised in older patients with suspected heart disease than it is in young, healthy people.

Electrophysiologic profile and efficacy of intravenous dofetilide (UK-68,798), a new class III antiarrhythmic drug, in patients with sustained monomorphic ventricular tachycardia☆

There is increasing evidence that class III antiarrhythmic agents may be superior to class I agents for the long-term treatment of life-threatening ventricular tachyarrhythmias. This open study evaluated the acute electrophysiologic effects, antiarrhythmic efficacy, and safety of different doses of intravenous dofetilide, a new class III drug, in 50 patients with sustained monomorphic ventricular tachycardia inducible by programmed electrical stimulation who had previously been unsuccessfully treated with 0 to 7 (median 3) other drugs. Intravenous dofetilide was administered over 60 minutes at the following dose levels: 1.5, 3.0, 6.0, 9.0, and 15.0 micrograms/kg. Significant class III activity was apparent at doses of 3.0 to 15.0 micrograms/kg, as evidenced by dose-related prolongation of the QTc interval by 13.4% to 14.2%, ventricular effective refractory period by 7.9% to 20.6%, and ventricular functional refractory period by 7.3% to 25.0%. The corresponding mean +/- SD plasma dofetilide concentrations ranged from 1.45 +/- 0.52 to 6.48 +/- 1.31 ng/ml. There was no evidence of reverse use-dependence. At these electrophysiologically active dose levels, intravenous dofetilide suppressed (complete response) or slowed (partial response) inducible ventricular tachycardia in 17 of 41 patients (41%) compared with 0 of 9 patients receiving only 1.5 micrograms/kg. The response rate was fairly uniform among the groups receiving 3.0, 6.0, 9.0, and 15.0 micrograms/kg. Intravenous dofetilide was hemodynamically well tolerated. Torsades de pointes (which was self-limiting) developed in only 1 patient, who was allocated to receive 15.0 micrograms/kg. There were no other proarrhythmic episodes or serious adverse effects. Further evaluation of the therapeutic potential of dofetilide in the management of life-threatening ventricular arrhythmias is justified.

Adenoviral-mediated gene transfer of vascular endothelial growth factor in critical limb ischemia: safety results from a phase I trial

Critical limb ischemia (CLI) is typifi ed by rest pain and/or tissue necrosis secondary to advanced peripheral arterial disease (PAD) and is characterized by diminution in limb per-fusion at rest. We tested the safety of an angiogenic strategy with CI-1023 (AdGV VEGF121.10), a replication-defi cient adenovirus encoding human vascular endothelial growth factor isoform 121 in patients with CLI as part of a phase I trial. Fifteen subjects >35 years of age with CLI and angiographic disease involving the infra-inguinal vessels underwent intramuscular injection of CI-1023 (4 3 108 to 4 3 1010 particle units, n = 13) or placebo (n = 2). All of the patients tolerated the injection well and there were no serious complications related to the procedure. Transient edema was noted in one patient. A total of 79 adverse events were reported over the course of one year. One death (day 136) and one malignancy (day 332) occurred in the CI-1023 group. CI-1023 appears to be well tolerated and safe for single-dose administration in patients with critical limb ischemia due to PAD. Further studies are needed to determine the efficacy of this form of therapeutic angiogenesis.