Aratana Commences Dosing Of First Patient In Studies of AT-005

Aratana Therapeutics, Inc.

, a pet therapeutics company focused on licensing, developing and commercializing innovative biopharmaceutical products for cats, dogs and other companion animals, today announced that it is currently enrolling patients in two nationwide clinical trials to evaluate its monoclonal antibody for canine T-cell lymphoma, AT-005, which is conditionally licensed by the USDA to aid in the treatment of dogs with lymphoma. These studies are not required by the USDA to obtain a full product license for AT-005, for which it is currently under review. They were designed by veterinary oncologists to evaluate AT-005 under real practice conditions, which will help Aratana and oncologists understand the clinical value of AT-005 once it is fully licensed by the USDA, which is anticipated to be in 2015. Specifically, the studies will evaluate AT-005 in combination with two different chemotherapy regimens used to treat dogs diagnosed with intermediate- to high-grade peripheral T-cell lymphoma. Steven St. Peter, M.D., President and Chief Executive Officer of Aratana Therapeutics, stated, "Aratana is committed to demonstrating the full clinical potential of our novel pet biologics, which may offer veterinarians a new paradigm for treating lymphoma in dogs. In addition to the positive safety and efficacy data upon which the USDA based our product licenses for our canine lymphoma monoclonal antibodies, we believe the results of these two market development studies will be instrumental for demonstrating the potential benefit of adding a biologic to standard chemotherapy. Similar regimens have had meaningful impact on patient outcomes in human drug development, and we believe our ability to demonstrate a similar effect for AT-005 will facilitate its adoption by veterinarians and pet owners." The studies are being conducted in coordination with Animal Clinical Investigation, LLC (ACI). Details are as follows: T-CHOMP (T cell – CHOP + Monoclonal antibody) Patient dosing has initiated in this randomized, blinded, placebo-controlled field study, which will enroll an estimated 48 client-owned dogs and is designed to assess the benefit of adding AT-005 to multi-agent CHOP chemotherapy (Cyclophosphamide, Hydroxydaunorubicin, Oncovin, and Prednisone). All patients will receive standard CHOP chemotherapy and will be randomized (1:1) to receive supplemental AT-005 or placebo. Patients will be dosed twice weekly for four weeks, once weekly for another 15 weeks, and monthly thereafter. The study duration is 18 months; however, if progressive disease occurs before the 18-month visit, dogs will be removed from the study at that time. The primary efficacy endpoint is progression-free survival (PFS), with a secondary endpoint of objective response rate (ORR). Investigators will also monitor patients for overall survival (OS). Adverse events will be evaluated and compared between treatment and placebo groups. This study is currently enrolling patients. For more information, please visit http://www.animalci.com/trials/t-chomp. T-LAB (T cell – Lomustine + monocolonal AntiBody) This randomized, blinded, placebo-controlled field study will enroll an estimated 60 client-owned dogs, and is designed to assess the benefit of adding AT-005 to single-agent lomustine (CCNU) chemotherapy. All patients will receive two three-week cycles of single-agent CCNU chemotherapy, after which patients that achieve partial or complete response will be randomized (1:1) to receive AT-005 or placebo twice per week for the next four weeks. Patients will continue to receive AT-005 or placebo every other week for another 8 weeks, after which they will be rechecked monthly. The total study duration is 12 months; however, patients will be removed from the study if their disease progresses before the 12-month visit. The primary efficacy endpoint is progression-free survival (PFS) and investigators will also monitor the duration of response and overall survival (OS). Adverse events will be evaluated and compared between treatment and placebo groups. This study is currently enrolling patients. For more information, please visit http://www.animalci.com/trials/t-lab.