Relative bioavailability between two teriparatide formulations in healthy volunteers.

OBJECTIVE: To compare the pharmacokinetics, relative bioavailability (RB), immunogenicity, and safety after a single dose of test or reference formulation of teriparatide in healthy human volunteers in order to demonstrate whether both products are similar. RESEARCH DESIGN AND METHODS: We compared pharmacokinetic parameters, immunogenicity, and safety after a single dose of two formulations (Osteofortil® and Forteo®) of teriparatide in a randomizedsequence, open-label, two-period crossover study in 24 healthy volunteers. The washout period between formulations was 7 days. Blood samples were collected at baseline and 0, 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 120, 150 minutes, and 3 and 4 hours after administration. Teriparatide concentrations were determined using ELISA. Adverse events were monitored. RESULTS: Geometric mean (90% CI) Cmax for test and reference formulations were 165.86 (153.35 - 212.13) and 175.37 (164.04 - 221.04) pg/mL, the AUC0-t was 14,932 (5,275 - 15,752) and 14,153 (1,861 - 16,875) pg×min/mL, and the AUC0-∞ was 16,147 (15,047 - 18,799) and 15,467 (14,473 - 18,126) pg×min/mL, respectively. The test/reference ratios (90% CI) for Cmax, AUC0-t, and AUC0-∞ were 94.58% (85.29 - 104.87), 105.5% (97.77 - 113.84), and 104.4% (96.97 - 112.39), respectively No subject reported adverse events. CONCLUSION: Test formulation met pharmacokinetic criteria for bioequivalence.

High-dose plasmid-mediated VEGF gene transfer is safe in patients with severe ischemic heart disease (Genesis-I). A phase I, open-label, two-year follow-up trial.

OBJECTIVES: We aimed to assess safety and, secondarily, the efficacy of intramyocardial high-dose plasmid-vascular endothelial growth factor (VEGF) 165 (pVEGF165) gene transfer in no-option patients with coronary artery disease (CAD). BACKGROUND: Controlled trials of pVEGF165 in CAD have shown little benefit. One possible reason is shortness of dosage. We have shown in large mammalian models of chronic myocardial ischemia and acute myocardial infarction that intramyocardial pVEGF165 at doses significantly higher than those used in recent phase II trials is safe and efficacious on myocardial perfusion, left ventricular function, and infarct size limitation. METHODS: Using an injection catheter, 10 patients with severe CAD not amenable for revascularization received 10 intramyocardial injections of 0.38 mg (total dose, 3.8 mg) pVEGF165 in zones exhibiting myocardial ischemia, as assessed by combined stress 99mTc-sestamibi single-photon emission computed tomography and stress echocardiography. RESULTS: No serious adverse events related to either VEGF or the injection procedure occurred over the 2-year follow-up. One patient suffered femoral artery thrombosis after a follow-up coronary angiography, successfully resolved with medical treatment. Six patients suffered uncomplicated coronary ischemic events during the second year follow-up. Angina functional class decreased from 2.6 ± 0.2 to 1.2 ± 0.3 (mean ± SEM, P < 0.05), quality of life increased from 56.9 ± 3.2 to 82.6 ± 2.4 (P < 0.05), the summed difference score of myocardial perfusion decreased from 13.4 ± 2 to 7.7 ± 1.8 (P < 0.04), and stress ejection fraction did not change (44.2 ± 3.6% to 47.8 ± 3.1%, P = NS). CONCLUSIONS: High-dose intramyocardial pVEGF165 is safe at 2 years follow-up in patients with severe CAD. The efficacy results observed must be taken cautiously given the uncontrolled, open-label study design.

Development of a Biosimilar of Agalsidase Beta for the Treatment of Fabry Disease: Preclinical Evaluation.

BACKGROUND AND OBJECTIVE: Fabry disease (FD) is a rare lysosomal storage disorder caused by a deficiency of the enzyme α-galactosidase A (aGal A). Since 2001, two different enzyme replacement therapies have been authorized, with agalsidase beta being used in most parts of the Western world. Currently, biosimilars of several expensive enzyme therapies are under development to improve their accessibility for patients. We present the preclinical results of the development of a biosimilar to agalsidase beta. METHODS: Produced in a Chinese hamster ovary (CHO)-cell system, the biosimilar aGal A Biosidus (AGABIO), was compared with agalsidase beta with respect to amino acid sequence, glycosylation, specific α-galactosidase activity, stability in plasma, and effects on cultured human Fabry fibroblasts and Fabry mice. RESULTS: AGABIO had the same amino acid composition and similar glycosylation, enzymatic activity, and stability as compared with agalsidase beta. After uptake in fibroblasts, α-galactosidase A activity increased in a dose-dependent manner, with maximum uptake observed after 24 h, which remained stable until at least 48 h. Both enzymes were localized to lysosomes. Reduction of accumulated globotriaosylceramide (Gb3) and lysoGb3 in cultured Fabry fibroblasts by AGABIO and agalsidase beta showed comparable dose-response curves. In Fabry knockout mice, after a single injection, both enzymes were rapidly cleared from the plasma and showed equal reductions in tissue and plasma sphingolipids. Repeated dose studies in rats did not raise any safety concerns. Anti-drug antibodies from patients with FD treated with agalsidase beta showed equal neutralization activity toward AGABIO. CONCLUSION: These findings support the biosimilarity of AGABIO in comparison with agalsidase beta. The clinical study phase is currently under development.

Effect of vascular endothelial growth factor gene transfer on infarct size, left ventricular function and myocardial perfusion in sheep after 2 months of coronary artery occlusion.

BACKGROUND: In large mammalian models of acute myocardial infarction (AMI), plasmid-mediated vascular endothelial growth factor (pVEGF) gene transfer has been shown to induce angio-arteriogenesis, proliferation of myocyte precursors and adult cardiomyocyte mitosis, reducing infarct size at 15 days after coronary artery occlusion. However, it is unknown whether these effects persist at longer follow-up times, nor how they affect cardiac performance. We thus assessed infarct size, left ventricular (LV) function and perfusion in 2-month-old ovine AMI. METHODS: Adult sheep with coronary artery occlusion were randomized to blindly receive ten intramyocardial injections of 3.8 mg of pVEGF or empty plasmid distributed at the infarct border. Three and 60 days later, LV perfusion (single-photon emission computed tomography) and function (stress echocardiography) were assessed. Finally, hemodynamics (LV catheterization), scar size and peri-infarct histology were studied. RESULTS: Infarct size was 30% smaller in pVEGF-treated sheep (23.6 ± 1.9% versus 32.7 ± 2.7% of the LV; p < 0.02). Percentage fractional shortening and wall thickening at the infarct border improved after pVEGF, as did myocardial perfusion and LV wall motion under pharmacological stress. Global LV function did not differ between groups, although the force-frequency response was preserved in pVEGF group and lost in placebo animals. These effects were associated with angio-arteriogenesis and proliferation of cardiomyocyte precursors. CONCLUSIONS: In sheep with AMI, pVEGF gene transfer affords long-term infarct size reduction, yielding regional LV function and perfusion improvement and reducing remodeling progression. These results suggest the potential usefulness of this approach in the clinical setting.

Field testing, gene flow assessment and pre-commercial studies on transgenic Solanum tuberosum spp. tuberosum (cv. Spunta) selected for PVY resistance in Argentina.

Solanum tuberosum ssp. tuberosum (cv. Spunta) was transformed with a chimeric transgene containing the Potato virus Y (PVY) coat protein (CP) sequence. Screening for PVY resistance under greenhouse conditions yielded over 100 independent candidate lines. Successive field testing of selected lines allowed the identification of two genetically stable PVY-resistant lines, SY230 and SY233, which were further evaluated in field trials at different potato-producing regions in Argentina. In total, more than 2,000 individuals from each line were tested along a 6-year period. While no or negligible PVY infection was observed in the transgenic lines, infection rates of control plants were consistently high and reached levels of up to 70-80%. Parallel field studies were performed in virus-free environments to assess the agronomical performance of the selected lines. Tubers collected from these assays exhibited agronomical traits and biochemical compositions indistinguishable from those of the non-transformed Spunta cultivar. In addition, an interspecific out-crossing trial to determine the magnitude of possible natural gene flow between transgenic line SY233 and its wild relative Solanum chacoense was performed. This trial yielded negative results, suggesting an extremely low probability for such an event to occur.

High level expression of bioactive recombinant human growth hormone in the milk of a cloned transgenic cow.

Transgenic farm animals have been proposed as an alternative to current bioreactors for large scale production of biopharmaceuticals. However, the efficiency of both methods in the production of the same protein has not yet been established. Here we report the production of recombinant human growth hormone (hGH) in the milk of a cloned transgenic cow at levels of up to 5 g l(-1). The hormone is identical to that currently produced by expression in E. coli. In addition, the hematological and somatometric parameters of the cloned transgenic cow are within the normal range for the breed and it is fertile and capable of producing normal offspring. These results demonstrate that transgenic cattle can be used as a cost-effective alternative for the production of this hormone.

Arteriogenesis induced by intramyocardial vascular endothelial growth factor 165 gene transfer in chronically ischemic pigs.

Exogenous vascular endothelial growth factor (VEGF) improves tissue perfusion in large animals and humans with chronic myocardial ischemia. Because tissue perfusion is mainly dependent on the arteriolar tree, we hypothesized that the neovascularizing effect of VEGF should include arteriogenesis, an effect not as yet described in large mammalian models of myocardial ischemia. In the present study we investigated the effect of intramyocardial plasmid-mediated human VEGF(165) gene transfer (pVEGF(165)) on the proliferation of vessels with smooth muscle in a pig model of myocardial ischemia. In addition, we assessed the effect of treatment on capillary growth, myocardial perfusion, myocardial function and collateralization. Three weeks after positioning of an Ameroid constrictor (Research Instruments SW, Escondido, CA) in the left circumflex artery, pigs underwent basal perfusion (single-photon emission computed tomography [SPECT] with (99m)Tc-sestamibi) and regional function (echocardiography) studies at rest and under dobutamine stress, and were then randomly assigned to receive transepicardial injection of pVEGF(165) 3.8 mg (n = 8) or placebo (empty plasmid, n = 8). All experimental steps and data analysis were done in a blinded fashion. Five weeks later, pVEGF(165)-treated pigs showed a significantly higher density of small (8-50 microm in diameter) vessels with smooth muscle, higher density of capillaries, and improved myocardial perfusion. These results indicate an arteriogenic effect of VEGF in a large mammalian model of myocardial ischemia and encourage the use of VEGF to promote arteriolar growth in patients with severe coronary artery disease.

Bizionia argentinensis sp. nov., isolated from surface marine water in Antarctica.

A marine bacterial strain, designated strain JUB59(T), was isolated from surface seawater in Antarctica and subsequently characterized. Cells were found to be Gram-negative, non-motile rods forming butyrous, shiny, yellowish orange colonies on marine agar. Growth occurred at 2-28 degrees C (optimally at 22-25 degrees C) but not at 30 degrees C; Na+ ions were required, but 9 % NaCl (w/v) was not tolerated. Phylogenetic analysis, based on comparisons of the complete 16S rRNA gene sequence of the novel isolate with the sequences of closely related strains, showed that strain JUB59(T) belonged to the family Flavobacteriaceae, representing a novel species of the genus Bizionia. The highest levels of sequence similarity were found with respect to Bizionia myxarmorum ADA-4(T) (97.4 %) and Bizionia algoritergicola APA-1(T) (97.1 %). However, the DNA-DNA relatedness of strain JUB59(T) with respect to these two strains was low (15.9-17.3 and 19.3-22.1 %, respectively). The predominant fatty acids of strain JUB59(T) were iso-15 : 1omega10c (18.1 %), iso-15 : 0 (17.3 %), anteiso-15 : 0 (13.9 %), iso-17 : 0 3-OH (9.2 %), 15 : 0 (6.0 %) and iso-16 : 0 3-OH (5.3 %). The main polar lipids were phosphatidylethanolamine, an aminolipid, an amino-positive phospholipid and two unidentified lipids. MK-6 was the major respiratory quinone (>90 %) and the DNA G+C content was 34 mol%. On the basis of the data obtained, strain JUB59(T) represents a novel species of the genus Bizionia, for which the name Bizionia argentinensis sp. nov. is proposed. The type strain is JUB59(T) (=DSM 19628(T)=CCM-A-29 1259(T)).

Cardiomyocyte hyperplasia after plasmid-mediated vascular endothelial growth factor gene transfer in pigs with chronic myocardial ischemia.

BACKGROUND: For over 40 years it has been proposed that cardiomyocyte hyperplasia may occur in hypertrophic human hearts. While this implies that heart myocytes can undergo cytokinesis, evidence of conventional cell division has been exceptionally reported. Recently, we found that gene transfer of vascular endothelial growth factor (VEGF) displays a mitogenic effect on adult cardiomyocytes. In the present study we searched for cardiomyocyte hyperplasia as evidence of VEGF-induced cardiomyocyte cytokinesis. METHODS: Three weeks after implanting an Ameroid constrictor at the origin of the left circumflex artery, 16 pigs were randomized to receive 10 direct intramyocardial injections of 3.8 mg of plasmid encoding for VEGF (pVEGF) or empty plasmid. Five weeks later, hearts were weighed, myocyte diameter was measured in tissue sections, and myocyte length and nuclei number were studied in isolated myocytes. A resting echocardiogram was performed immediately before reoperation and before sacrifice to evaluate global and regional left ventricular function. Investigators were blinded to the study groups and nature of the injectate until the end of data analysis. RESULTS: No heart weight differences existed between groups. However, in the ischemic myocardium, pVEGF-treated hearts had 22% more cardiomyocytes per unit volume and exhibited significantly more oligonucleated (1 or 2 nuclei) cardiomyocytes than hearts receiving empty plasmid. CONCLUSIONS: In pigs with chronic myocardial ischemia, VEGF gene transfer induced cardiomyocyte cytokinesis, as revealed by cardiomyocyte hyperplasia. Our finding extends the previously reported mitogenic effect of VEGF on adult cardiomyocytes and supports the hypothesis that VEGF may have a therapeutic role in diseases characterized by myocardial cell loss.

Reducción del tamaño del infarto de miocardio mediante la transferencia génica de VEGF en ovejas / Myocardial infarct size reduction after VEGF gene transfer in sheep

La transferencia génica de plásmido codificante para VEGF (pVEGF) induce angiogénesis, incremento del índice mitótico e hiperplasia miocítica en cerdos con isquemia miocárdica crónica. El presente trabajo se realizó con el objetivo de estudiar el efecto del pVEGF sobre el tamaño del infarto de miocardio. Una hora después de la ligadura de la descendente anterior, 28 ovejas de 23 ± 0,5 kg se agruparon al azar para recibir 10 inyecciones intramiocárdicas de 3,8 mg de pVEGF (n = 14) o placebo (n= 14) distribuídas en la periferia del infarto. La función miocárdica se estudió con SPECT gatillado y los animales se sacrificaron 7, 10 y 15 días después del tratamiento. El tamaño del infarto fue el 34 por ciento menor en el grupo tratado que en el placebo (placebo: 17,1 ± 2,1 por ciento, VEGF: 11,2 ± 1,5 por ciento, p < 0,05) a los 15 pero no a los 10 días. Aunque hubo una leve tendencia a favor del grupo tratado, la mejoría de la función miocárdica no fue diferente entre grupos (placebo: 3,3 ± 1,4; VEGF: 3,8 ± 2,4; p = NS). El estudio histológico mostró que los mecanismos involucrados fueron la respuesta angiogénica a los 7 días (placebo: 676 ± 31 capilares / mm²: VEGF: 1925 ± 262; p <0,05), la menor fibrosis periinfarto a los 10 días (contenido de colágeno; placebo: 70, 1 ± 1,7 por ciento; VEGF: 43,5 ± 4,4 por ciento; p < 0,05); la proliferación de mioblastos a los 7 y 10 días. La expresión del pVEGF fue positiva a los 3 (ARNm), 7 y 10 días. La expresión del pVEGF fue positiva a los 3 (ARNm), 7 y 10 días (proteína) posadministración. Conclusión: A los 15 días la transferencia génica de VEGF humano reduce el tamaño de infarto en ovejas mediante angiogénesis, disminución de la fibrosis e inducción de proliferación de mioblastos (miocardiogénesis).