Cohort Prospective Study to Evaluate Immunogenicity of Epodion® (Biosimilar Epoetin-a) in Anemia Associated with Chronic Kidney Disease (CKD) Patients.

BACKGROUND: Anemia due to chronic kidney disease (CKD) is often associated with decreased erythropoietin (EPO) levels in the blood. Treatments available are improving blood iron levels and administration of exogenous EPO (rhEPO). This study aims to assess the safety and immunogenicity of Epodion, a biosimilar rhEPO product, in haemodialysis patients with CKD-associated anaemia in three Indonesian hospitals. METHODS: This prospective, open label, single arm, and multicenter study enrolled patients with anemia associated with CKD under hemodialysis treatment. Patient eligibility was assessed within the 4-week screening period. Blood samples for determination of erythropoietin antibody (Anti-Drug Antibody) were taken at week-0, 24, and 52 using a validated and highly sensitive bridging ELISA method. Evaluation of Neutralizing Antibody (NAb) was carried out to confirm the impact of the antibody to pharmacological activity (e.g., antibody-mediated PRCA) when the ADA detection of patients was positive after screening and confirmatory assay. RESULTS: Results from all tested patients show that Epodion could maintain hemoglobin and hematocrit levels. ADA detection using ELISA assay yielded negative results for all plasma samples of week-24 and week-52, so the evaluation of NAb was not carried out. No adverse events were considered relevant to tested product. CONCLUSION: This study proves no immunogenic effect of Epodion on stimulating immune system's antibodies in Indonesian patients with CKD-associated anemia.

Enhanced percutaneous delivery of recombinant human epidermal growth factor employing nano-liposome system.

We encapsulated recombinant human epidermal growth factor (rhEGF) into nano-liposomes (NLs) system for topical delivery. The rhEGF-loaded NLs were prepared using a high pressure homogenization method. Morphology and overall particle distribution of NLs were investigated using transmission electron microscopy (TEM) and high resolution microscope (CytoViva™). Particle size, zeta (ζ) potential and encapsulation efficiency were measured and the percutaneous delivery of NLs was evaluated using Franz diffusion cells and immunofluorescence confocal laser scanning microscopy (CLSM). The mean particle size, zeta potential and encapsulation efficiency of the NLs were 155.57 ± 2.59 nm, -57.92 ± 4.35 mV and 9.00 ± 0.39%, respectively. TEM and microscopic analysis showed spherical, very even-sized vesicles approximately 150 nm. The skin permeation and localization of rhEGF were enhanced by NLs. CLSM image analysis provided that the NLs enhanced the permeation and localization of rhEGF in rat skin by facilitating entry through pores of skin.

Formulation and In Vitro Penetration Study of Recombinant Human Epidermal Growth Factor-Loaded Transfersomal Emulgel.

Purpose: Recombinant human epidermal growth factor (rhEGF) is a 6045-Da peptide that promotes the cell growth process, and it is also used for cosmetic purposes as an anti-aging compound. However, its penetration into skin is limited by its large molecular size. This study aimed to prepare rhEGF-loaded transfersomal emulgel with enhanced skin penetration compared with that of non-transfersomal rhEGF emulgel. Methods: Three transfersome formulations were prepared with different ratios between the lipid vesicle (phospholipid and surfactant) and rhEGF (200:1, 133:1, and 100:1) using a thin-film hydration-extrusion method. The physicochemical properties of these transfersomes and the percutaneous delivery of the transfersomal emulgel were evaluated. Long-term and accelerated stability studies were also conducted. Results: The 200:1 ratio of lipid to drug was optimal for rhEGF-loaded transfersomes, which had a particle size of 128.1 ± 0.66 nm, polydispersity index of 0.109 ± 0.004, zeta potential of -43.1 ± 1.07 mV, deformability index of 1.254 ± 0.02, and entrapment efficiency of 97.77% ± 0.09%. Transmission electron microscopy revealed that the transfersomes had spherical and unilamellar vesicles. The skin penetration of rhEGF was enhanced by as much as 5.56 fold by transfersomal emulgel compared with that of non-transfersomal emulgel. The stability study illustrated that the rhEGF levels after 3 months were 84.96-105.73 and 54.45%-66.13% at storage conditions of 2°C-8°C and 25°C ± 2°C/RH 60% ± 5%, respectively. Conclusion: The emulgel preparation containing transfersomes enhanced rhEGF penetration into the skin, and skin penetration was improved by increasing the lipid content.

Analysis of protein adsorption characteristics to nano-pore silica particles by using confocal laser scanning microscopy.

The effect of average pore size of nano-pore silica particles on protein adsorption characteristics was determined experimentally by the dissociation constant and the adsorption capacity determined from the Langmuir equation. As the average pore size was increased from 2.2 to 45 nm, the BSA adsorption capacity increased from 16.8 to 84.3 mg/g-silica so as the equilibrium constant (from 2.6 to 9.4 mg/ml). Using confocal microscopy with fluorescence labeling, we could visualize the protein adsorption in situ and determine the minimum pore size required for efficient intraparticle adsorption. The confocal microscopy analysis revealed that BSA was adsorbed mainly on the surface of the particles with a smaller pore size, but diffused further into the interstitial surface when it was sufficiently large. It was concluded that for BSA whose Stoke's diameter is ca. 3.55 nm the minimum pore size of about 45 nm or larger was required for a sufficient adsorption capacity.

Enzymic cleavage of fusion protein using immobilized urokinase covalently conjugated to glyoxyl-agarose.

We immobilized urokinase (UK) by covalent attachment to activated Sepharose 6B-CL through multi-point amine coupling and evaluated its performance in cleaving a fusion protein, which consisted of recombinant human growth hormone (hGH) and a fragment of glutathione S-transferase that was linked by a tetrapeptide of a UK-specific recognition sequence. Packing densities of aldehyde groups on the activated agarose surface could be controlled in a gel range of 7-60 micromol/ml aldehyde by the amount of glycidol used. The immobilization yield was nearly 100% at pH 10.5, and the specific activity of the immobilized UK was equivalent to about 80% of soluble UK under the assay conditions. The immobilized UK showed an improvement in pH and thermal stability, probably due to the structural rigidity imparted by multi-point linkages to the matrix. The cleavage rate by the immobilized UK was lower than that of the soluble enzyme but the side reaction of cryptic cleavage was significantly decreased, which might suggest that the enzyme's specificity was altered by the immobilization. Cleavage yield in the column packed with immobilized UK was dependent on the feed rate, and the yield was approx. 80% of that of the soluble UK. The monomeric hGH could be obtained by selectively precipitating the uncleaved fusion protein and the GST fragments at an acidic pH.

Purification of soluble human epidermal growth factor (hEGF) from recombinant Escherichia coli culture broth by using expanded-bed adsorption chromatography.

Human epidermal growth factor (hEGF) secreted by recombinant Escherichia coli was purified from culture broth by expanded-bed adsorption (EBA) chromatography, strong anion-exchange chromatography and finally preparative reversed-phase HPLC (RP-HPLC). The EBA chromatography step simultaneously captured the hEGF by cationic exchanger and removed the cellular biomass from the diluted culture broth. This step was carried out at high throughput, and resulted in a high yield (>90%) and a purification factor of approx. 20-fold to >80% purity. Its process performance was well maintained during a 16-fold scale-up. After the successive purification steps of anion-exchange chromatography and RP-HPLC, the overall yield was approx. 84% and the purity was satisfactory (>99.5%). It was concluded that the purification process was very efficient and scaleable, warranting its implementation in large-scale manufacturing.