Non-Diffusive Botulinum Toxin Causing Local Muscle Paralysis, And Purification Method Thereof
Patent No. EP2578228 (titled "Non-Diffusive Botulinum Toxin Causing Local Muscle Paralysis, And Purification Method Thereof") was filed by Medexgen on May 13, 2011. The application was issued on Nov 15, 2017.
Patent Summary
This invention provides a method for purifying a non-spreading botulinum toxin type A to prevent systemic diffusion and associated side effects. The process involves subjecting a botulinum toxin type A product—previously obtained via acid precipitation or subsequent chromatography—to ion-exchange chromatography using a buffer with pH 4.5–5.5 and 0.02–0.2 M sodium chloride (NaCl). The non-spreading toxin is isolated by collecting a specific subfraction characterized by an A260/A280 value of 0.4–0.6. The resulting preparation comprises at least 150 ppb Zn, 80 ppb Fe, and 140 ppb Mg ions per 100 U. The non-spreading property is verified by injecting the toxin into mouse calf muscles, demonstrating localized paralysis and a survival rate of at least 80% at 96 hours post-injection.
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EP2578228
- Application Number
- EP11789976A
- Filing Date
- May 13, 2011
- Status
- Revoked
- May 13, 2022
- Publication Date
- Nov 15, 2017
- External Links
- Slate, Register , Google Patents