The first anion exchange chromatography in the four chromatography steps of the r-hGH manufacturing process was validated in this study, using a validation protocol consistent with both policy and standard operation procedure (SOP). The first anion exchange chromatography was conducted with a DEAE Sepharose Fast Flow Resin equilibrated with 50 mM Tris-HCl buffer (pH 8.2). The activated r-hGH solution obtained from the inclusion body was loaded onto a column and eluted with a linear gradient of 80-300 mM Tris-HCl buffer (pH 8.2) at a flow rate of 25 L/h. Several buffer solutions used in the first anion exchange chromatography were first validated and satisfied the acceptance criteria preestablished as follows; pH: 8.2, endotoxin: <0.8 EU/mL, bioburden test: negative. Three consecutive lots of crude r-hGH solutions were generated via anion exchange chromatography, which was operated within the operating parameters pre-established via in-process control. When the intermediate products (crude Met-hGH solutions) of all three lots were assessed in accordance with the pre-established sampling plan and quality control tests, all three tested lots satisfied the acceptance criteria preestablished for the following purification process as fallows: endotoxin: <= 350 EU/mg, ECP: <= 42 ppm, IEF: same removal distance, r-hGH content in Native-PAGE: >73%, purity by HPLC: >= 86%, purification yield by UV scanning: 32-36%. Therefore, the first anion chromatography process was well validated in this study, and consistently yields crude r-hGH solutions that fulfill the pre-established criteria for the next purification process. (C) 2008 Elsevier Ltd. All rights reserved.