Vivesto AB announced that the US Veterinary Review Board Clinical Studies Committee approved the company's planned Paccal Vet open label, pilot clinical study in dogs with splenic hemangiosarcoma following splenectomy. Clinical sites have been chosen and will be ready to start activities after supply of Paccal Vet (investigational veterinary product, IVP) in January. A planned interim analysis is expected in the second half of 2024.

The Paccal Vet development program was discussed with FDA earlier this year. No further Agency approval is required prior to study start. The study is an open label, exploratory indication finding study in dogs with different stages of splenic hemangiosarcoma (HSA) following splenectomy.

The study will include 4 treatment cycles of Paccal Vet (paclitaxel micellar) and it is planned to investigate 2 cohorts. Each cohort is planned to include a maximum of 23 patients. The study will be conducted at 6 clinical sites in Washington and Oregon.

First patients are expected to be dosed in early 2024 and a planned interim analysis is expected in the second half of 2024. If promising activity in either cohort is shown, the study shall be followed by a pivotal study designed to confirm the initial findings of this pilot study and to gather further evidence on the safety and efficacy of Paccal Vet in dogs with splenic hemangiosarcoma. Vivesto's drug candidate Paccal Vet consists of paclitaxel formulated with the company's proprietary XR-17 technology.

Vivesto has previously shown good safety of Paccal Vet in the treatment of various types of cancer in dogs. The absence of the solvent cremophor, to which dogs are particularly sensitive, may reduce the risk of serious side effects and death associated to the treatment. Paccal Vet also does not require the addition of human albumin, which when used in dogs can cause hypersensitivity reactions and reduced treatment effectiveness.