SBIR-STTR Award

Horses and cattle are susceptible to the neurotoxin produced by Clostridium botulinum Type C, one of the types of botulism. The purpose of this project is to develop a toxoid to protect horses and cattle (particularly dairy cattle) against this disease. OBJECTIVES: The overall objective of this project is to develop a toxoid for the protection of horses and cattle against Type C botulism, be it a toxemia (forage poisoning) or a toxicoinfection (equine grass sickness, visceral botulism in cattle). This toxoid will eventually be produced in Neogen Corporation's vaccine facility located in Tampa, FL. This facility is currently licensed for the production of BotVax B, a toxoid for equine use that protects animals against Shaker Foal Syndrome caused by a toxicoinfection with Clostridium borulinum Type B. APPROACH: This work plan is divided into five separate Tasks: 1. Screen strains of Clostridium botulinum Type C in various media to determine which strain and culture conditions yield the most toxin production; 2. Develop a purification scheme for the commercial production of Type C neurotoxin; 3. Transfer technology from a laboratory facility to a production facility in Tampa, FL; 4. Prepare 3 serials required for licensing; and, 5. Develop a potency test to ensure consistant production of acceptable product. PROGRESS: 2004/05 TO 2004/12 Five strains of Clostridium botulinum Type C were screened for the production of Type C neurotoxin. One strain, the Stockholm strain, was chosen for the production of this toxin. Culture conditions were optimized for the production of this neurotoxin and fermentations for large scale production were completed. This neurotoxin was purified from the culture supernatants resulting from the fermentations and toxoided for inclusion into a finished product. Finished product could not be tsted for potency in a Guinea Pig model due to the short duration of this grant. Production records and an Outline of Production were prepared for eventual submission to USDA Veterinary Services in support of licensure after completion of the potency test development. IMPACT: 2004/05 TO 2004/12 Type C botulism in both horses and dairy cattle is an increasing concern in the western part of the U.S. This toxoid will allow for the immunization of susceptible animals to prevent this disease. Additional testing for safety and efficacy is necessary prior to the licensing of this product by USDA for sale

Type C botulism is becoming more frequent in horses in the US due to changes modernization has made in harvesting of silage fed to farm animals. This project will determine the safety of and effectiveness of an experimental toxoid for the prevention of this illness in horses. The overall objective is to determine the safety and efficacy of a toxoid for the protection of horses against Type C botulism. This toxoid was produced in Neogen Corporation's vaccine facility located in Tampa, FL. This facility is currently licensed for the production of BotVax B, a toxoid for equine use that protects animals against Shaker Foal Syndrome caused by a toxicoinfection with Clostridium botulinum Type B. The US Department of Agriculture has granted permission to experimentally produce Type C toxoid in this facility. This facility contains a Biosafety Level Three (BSL3) suite equipped with a New Brunswick MPP80 fermentor, and is registered under the Select Agent Program (42 CFR Part 73), Registration #C20031123-0147. Individuals at the facility working with strains of Clostridium botulinum are immunized with Pentavalent botulism toxoid distributed by the Centers for Disease Control and Prevention under BB IND 161 as an investigational new drug. APPROACH: The Work Plan is divided into three Tasks: Task 1 is to develop a Potency Test and submission of paperwork to USDA for approval to conduct safety and efficacy testing. A potency test is to be modeled after that currently in use for determination of BotVax B potency. This involves the injection of 10 Guinea Pigs with toxoid and subsequent bleeding of the animals 45 days after injection. Pooled sera is then tested in CFW mice for its neutralizing ability against Type C botulism toxin. This neutralizing ability is then compared to that of a reference antisera of known International Unitage. This must be done prior to the submission of the Outline of Production to USDA. Task 2 is to determine the safety of the produced toxoid in the target species, horses. This will be performed at three different geographical sites in the US after approval and permission to ship experimental vaccine is obtained from USDA. This will involve the injection of horses at three different intervals with 2 ml of the toxoid. Animals will be monitored during the course of these studies for both local and systemic events. Task 3 is to determine the efficacy of the produced toxoid in the target species. This involves immunization of horses at the recommended dosage and intervals that will be listed on the product label. Upon 2-3 weeks after completion of the last injection, animals will be challenged intravenously with Type C botulism toxin. Animals will be monitored for symptoms of botulism and given petavalent botulism antitoxin upon appearance of any symptoms associated with botulism. A final report will be written upon completion fo these studies and submissions prepared for submission to USDA for product licensure. PROGRESS: 2005/09 TO 2006/09 Six different University facilities across the United States have been contacted and have agreed to participate in the Safety Studies for this product. In addition, Dr. Whitlock of the University of Pennsylvania has agreed to perform the Efficacy part of this study at Kennett Square, Pennsylvania. Dr. Whitlock's facility is registered with the Centers for Disease Control and Prevention under the Select Agent Program. Futher progress on this project has been delayed due to the decision to move the production facility for this product from Tampa, FL to Lansing, MI due to power outages and hurricanes interrupting the production schedule at this facility. This move is scheduled to be completed in the first quarter of calendar year 2007. A one year extension for this project will be requested for the completion of this project. IMPACT: 2005/09 TO 2006/09 It is anticipated that the immunization of horses with this product will protect them from Type C botulism. This type of botulism is most frequently observed in the western and northern sections of the U.S