Conventional Test Method:

Mouse LD₅₀ Assay for Botulinum Toxin Potency Testing

Alternative Test Method:

Name & Description:

Mouse Abdominal Ptosis Assay or Flaccid Paralysis
(Non-lethal Mouse Model for Botulinum Toxin Potency Testing)

This method assesses local paralysis of the abdominal muscle. A palsy of the abdominal muscle develops after subcutaneous injection of low level of toxin into the mouse.

Validation Status:

UK: Validated at NIBSC for potency testing of BoNT products

US: ICCVAM workshop panel concluded that the Abdominal Ptosis Assay has the potential to replace the LD50 endpoint, but further validation studies are required (2008)

Regulatory Status:

EU: Listed in the European Pharmacopoeia for BoNT type A for injection (2005)

UK: Used by NIBSC when in vitro test  is inconclusive

US: None

Effect or Potential Effect on Animal Use:

Refinement
(Does not rely on death as an endpoint)

References:

• Adler S., Bicker G., Bigalke H., Bishop C., Blümel J., Dressler D., Fitzgerald J., Gessler F., Heuschen H., Kegel B., Luch A., Milne C., Pickett A., Ratsch H., Ruhdel I., Sesardic D., Stephens M., Stiens G., Thornton P.D., Thürmer R., Vey M., Spielmann H., Grune B. and Liebsch M. (2010) The current scientific and legal status of alternative methods to the LD50 test for Botulinum neurotoxin potency testing. ATLA 38(4):315-330.
• ICCVAM (2008) Report on the ICCVAM-NICEATM/ECVAM Scientific Workshop on Alternative Methods to Refine, Reduce or Replace the Mouse LD₅₀ Assay for Botulinum Toxin Testing. Bethesda MD: National Institutes of Health (NIH).
• Seseardic D., McLellan K., Ekong T.A. and Das R.G. (1996) Refinement and validation of an alternative bioassay for potency testing of therapeutic botulinum type A toxin. Pharmacology & Toxicology 78(5):283-288.

Information Last Reviewed:

May 2012