Stabilization of clostridium botulinum neurotoxin complex

Abstract

A stable composition including a non-covalent complex of a botulinum neurotoxin and a cyclodextrin and a method of preserving botulinum neurotoxin and for producing a botulinum neurotoxin composition with improved stability properties in an efficient and economically advantageous manner. The invention seeks to alleviate the problems associated with rapid degradation or denaturation of botulinum neurotoxin by providing a novel composition that exhibits improved stability properties. The botulinum neurotoxin is preferably stabilized by forming a cyclodextrin complex.

1 . A method for providing a stabilized neurotoxin composition which comprises:
 forming anon-covalent complex of a botulinum neurotoxin and a cyclodextrin having cyclic multicyclopyranose units connected by alpha-(1-4) linkages, wherein the cyclodextrin and the botulinum neurotoxin are provided in amounts sufficient to form the complex and stabilize the composition such that the composition has a shelf life of at least four weeks.   
   
   
       2 . The method of  claim 1 , which further comprises imparting improved stability to the botulinum neurotoxin by providing the cyclodextrin and botulinum neurotoxin in a molar ratio of at least 25:1 to 50:1. 
   
   
       3 . The method of  claim 1 , wherein about 55% to about 80% of the botulinum neurotoxin remains as the complex for a period of at least 2 weeks. 
   
   
       4 . The method of  claim 1 , wherein the botulinum neurotoxin has about 2% to less than 65% degradation over a period of time of about 23 weeks at storage temperatures that are between 4° C. and 25° C. 
   
   
       5 . The method of  claim 1 , wherein the botulinum toxin is selected from the group consisting of botulinum toxin types A, B, C, D, E, F, and G. 
   
   
       6 . The method of  claim 1 , wherein the botulinum toxin is purified prior to forming the complex. 
   
   
       7 . The method of  claim 1 , wherein the cyclodextrin is α-cyclodextrin, β-cyclodextrin, or γ-cyclodextrin. 
   
   
       8 . The method of  claim 1 , which further comprises providing a stabilizing solution for the cyclodextrin wherein the solution further comprises a phosphate buffer. 
   
   
       9 . The method of  claim 8 , wherein the buffer is sodium phosphate and the pH of the solution is about 6.8 to about 7.6. 
   
   
       10 . The method of  claim 1 , which further comprises providing the complex in the form of an injectable solution or dried preparation. 
   
   
       11 . A method for providing a stabilized neurotoxin composition comprising a botulinum neurotoxin and a cyclodextrin, which method comprises providing the cyclodextrin in an amount sufficient to form a non-covalent complex with the botulinum neurotoxin, and imparting stability to the botulinum neurotoxin by providing the cyclodextrin and the botulinum neurotoxin in a molar ratio of at least 25:1 to 50:1, wherein the complex exhibits improved stability compared to the neurotoxin alone as evidenced by a shelf life of at least four weeks with about 55% to about 80% of the botulinum neurotoxin remaining as the complex for a period of at least 2 weeks and by exhibiting less than 65% degradation over a period of time of about 23 weeks at storage temperatures that are between 4° and 25° C. 
   
   
       12 . The method of  claim 11 , wherein the botulinum toxin is selected from the group consisting of botulinum toxin types A, B, C, D, E, F, and G. 
   
   
       13 . The method of  claim 11 , wherein the botulinum toxin is purified prior to forming the complex. 
   
   
       14 . The method of  claim 11 , wherein the cyclodextrin is α-cyclodextrin, β-cyclodextrin, or γ-cyclodextrin. 
   
   
       15 . The method of  claim 11 , wherein the cyclodextrin is present in a stabilized solution that further comprises a phosphate buffer. 
   
   
       16 . The method of  claim 15 , wherein the buffer is sodium phosphate and the pH of the solution is about 6.8 to about 7.6. 
   
   
       17 . The method of  claim 11 , wherein the composition is in the form of an injectable solution or dried preparation. 
   
   
       18 . A non-covalent complex of a botulinum neurotoxin and cyclodextrin produced according to the method of  claim 1 . 
   
   
       19 . A non-covalent complex of a botulinum neurotoxin and cyclodextrin produced according to the method of  claim 11 . 
   
   
       20 . A non-covalent complex of a botulinum neurotoxin and a cyclodextrin having cyclic multicyclopyranose units connected by alpha-(1-4) linkages.