Compositions and methods to prevent aav vector aggregation

Abstract

Compositions and methods are provided for preparation of concentrated stock solutions of AAV virions without aggregation. Formulations for AAV preparation and storage are high ionic strength solutions (e.g. μ˜500 mM) that are nonetheless isotonic with the intended target tissue. This combination of high ionic strength and modest osmolarity is achieved using salts of high valency, such as sodium citrate. AAV stock solutions up to 6.4×10 13 vg/mL are possible using the formulations of the invention, with no aggregation being observed even after ten freeze-thaw cycles. The surfactant Pluronic® F68 may be added at 0.001% to prevent losses of virions to surfaces during handling. Virion preparations can also be treated with nucleases to eliminate small nucleic acid strands on virions surfaces that exacerbate aggregation.

We claim: 
     
         1 . A composition for the storage of purified virus particles, comprising:
 purified virus particles;   a pH buffer; and   excipients comprising one or more multivalent ions; wherein the ionic strength of the composition is greater than about 200 mM.   
     
     
         2 . The composition of  claim 1 , wherein the purified virus particles are AAV virus particles. 
     
     
         3 . The composition of  claim 1 , wherein one of the one or more multivalent ions is citrate. 
     
     
         4 . The composition of  claim 1 , further comprising Pluronic® F68. 
     
     
         5 . The composition of  claim 4 , wherein the Pluronic® F68 is present at 0.001%. 
     
     
         6 . The composition of  claim 1 , wherein the pH buffer is 10 mM Tris, pH 8.0 and the excipients comprise 100 mM sodium citrate. 
     
     
         7 . The composition of  claim 1 , wherein the average particle radius (Rh) of the purified virus particles is less than about 20 nm as measured by dynamic light scattering. 
     
     
         8 . The composition of  claim 1 , wherein recovery of the purified virus particles is at least about 90% following filtration of the composition of virions through a 0.22 μm filter. 
     
     
         9 . A method of preventing aggregation of virions in a preparation of virions, comprising treating said preparation of virions with Benzonase®. 
     
     
         10 . The method of  claim 9 , wherein, after Benzonase® treatment, the average particle radius (Rh) of the virions in the preparation of virions is less than about 20 nm as measured by dynamic light scattering. 
     
     
         11 . The method of  claim 9 , wherein, after Benzonase® treatment, recovery of the virions is at least about 90% following filtration of the preparation of virions through a 0.22 μm filter.