Josephine H Cheng1, Yu-Wen Wu2, Chen-Yun Wang2, Sharon S Wu1, Cheum L Hong2, Karen W Chan3, Leo X Liao4, Xisheng Cao4, Bin Wang4, Thierry Burnouf2,5. 1. Merck Ltd, Taiwan. 2. Graduate Institute of Biomedical Materials and Tissue Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan. 3. Merck Pte Ltd, Singapore. 4. Merck Chemicals (Shanghai) Co. Ltd, China. 5. International PhD Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan.
Abstract
BACKGROUND: Plasma-derived immunoglobulins (IgG) are essential medicines that are in worldwide shortage, especially in low- and middle-income countries. Optimised manufacturing processes can increase supply. We evaluated various new process steps for IgG fractionation. MATERIAL AND METHODS: A crude, worst-case, IgG intermediate obtained by caprylic acid fractionation of cryoprecipitate-poor plasma was used as starting experimental material. It was processed inline by Fractogel® (Merck) TMAE anion-exchanger to deplete IgA and IgM, Eshmuno® P (Merck) anti-A and anti-B affinity chromatography to remove anti-A and anti-B isoagglutinins, 0.3% TnBP-1% Triton X-100 (S/D) treatment, C18 chromatography for removal of S/D agents, and single-pass tangential flow filtration (SPTFF) concentration to 20%. Quality, safety, and recovery were evaluated at small and pilot scales to assess purity, removal of IgA, IgM isoagglutinins, S/D agents, thrombogenic factors, and lack of toxicity in a cell model. RESULTS: The starting IgG intermediate contained approximately 90% IgG, IgA, and IgM and 10% albumin. Fractogel® TMAE, equilibrated in 25 mM sodium acetate-pH 6.0 and loaded with up to 225 mg of IgG/mL, could remove IgA and IgM, with over 94% IgG recovery with preserved sub-class distribution in the flow-through. Sequential Eshmuno®-P anti-A and anti-B columns efficiently removed isoagglutinins. The C18 packing, used at up to 17 mL of S/D-IgG solution per mL, removed TnBP and Triton X-100 to less than 1 and 2 ppm, respectively. The 20% purified IgG was devoid of activated factor XI and thrombin generation activity. DISCUSSION: This purification sequence yields a >99% pure, 20% (v/v) IgG product, depleted of IgA, isoagglutinins, and thrombogenic markers, and should be implementable on various IgG intermediates to help improve the supply of immunoglobulins.
BACKGROUND: Plasma-derived immunoglobulins (IgG) are essential medicines that are in worldwide shortage, especially in low- and middle-income countries. Optimised manufacturing processes can increase supply. We evaluated various new process steps for IgG fractionation. MATERIAL AND METHODS: A crude, worst-case, IgG intermediate obtained by caprylic acid fractionation of cryoprecipitate-poor plasma was used as starting experimental material. It was processed inline by Fractogel® (Merck) TMAE anion-exchanger to deplete IgA and IgM, Eshmuno® P (Merck) anti-A and anti-B affinity chromatography to remove anti-A and anti-B isoagglutinins, 0.3% TnBP-1% Triton X-100 (S/D) treatment, C18 chromatography for removal of S/D agents, and single-pass tangential flow filtration (SPTFF) concentration to 20%. Quality, safety, and recovery were evaluated at small and pilot scales to assess purity, removal of IgA, IgM isoagglutinins, S/D agents, thrombogenic factors, and lack of toxicity in a cell model. RESULTS: The starting IgG intermediate contained approximately 90% IgG, IgA, and IgM and 10% albumin. Fractogel® TMAE, equilibrated in 25 mM sodium acetate-pH 6.0 and loaded with up to 225 mg of IgG/mL, could remove IgA and IgM, with over 94% IgG recovery with preserved sub-class distribution in the flow-through. Sequential Eshmuno®-P anti-A and anti-B columns efficiently removed isoagglutinins. The C18 packing, used at up to 17 mL of S/D-IgG solution per mL, removed TnBP and Triton X-100 to less than 1 and 2 ppm, respectively. The 20% purified IgG was devoid of activated factor XI and thrombin generation activity. DISCUSSION: This purification sequence yields a >99% pure, 20% (v/v) IgG product, depleted of IgA, isoagglutinins, and thrombogenic markers, and should be implementable on various IgG intermediates to help improve the supply of immunoglobulins.