Optimal placement of a robust solvent/detergent process post viral ultrafiltration of an immune gamma globulin
The solvent-detergent (S/D) process is used to inactivate enveloped viruses in plasma products. While concentrations of 1.0% detergent and 0.3% tri-n-butyl phosphate solvent have been considered necessary for robust removal of viral activity, we show the effectiveness of solvent-detergent treatment after fractionation and nanofiltration of an immune gamma globulin preparation, which required significantly reduced concentrations of solvent and detergent. Reduced levels of solvent and detergent lead to greater efficiencies in their removal post-inactivation with the potential for greater yields and decreased processing costs.
1. A method of virus inactivation in a post-manufacture immunoglobulin solution comprising:
reducing the potential virus load of the immunoglobulin solution,
adjusting the protein concentration of the immunoglobulin solution to equal or less than 6.0% w/v,
adjusting the pH of the immunoglobulin solution to 6.3-6.4,
contacting the immunoglobulin solution with 0.03% to 0.06% w/v of a di- or tri-alkyl phosphate solvent and 0.1% to less than 0.2% w/v of a non-ionic detergent for about 1 minute to about 1 hour at a temperature of 15-25° C.
2. The method of claim 1 wherein the immunoglobulin is anti-D immunoglobulin.
3. The method of claim 2 wherein the di- or tri-alkyl phosphate is tri-n-butyl-phosphate and the non-ionic detergent is an oxyethylated alkylphenol.
4. The method of claim 3 wherein the oxyethylated alkylphenol is a Triton®.
5. The method of claim 4 wherein the immunoglobulin solution is contacted with di- or tri-alkyl phosphate is present at 0.06% w/v and the non-ionic detergent is present at 0.2% w/v.
6. The method of claim 1 additionally comprising the step of removing the solvent and detergent from the immunoglobulin solution by a method selected from passage through a C-18 column, diafiltration through membranes, adsorption onto chromatographic supports, adsorption onto affinity chromatographic supports, ultrafiltration, filtration and adsorption, and admixture with adsorbent.
7. The method of claim 6 wherein the method is admixture with adsorbent.
8. The method of claim 7 wherein the adsorbent is a silica bead adsorbent material.
9. The method of claim 8 additionally comprising the step of removing the adsorbent from the immunoglobulin solution.