Penn Vet | CCC Clinical Trials - Trial of ALVAC® IL-2 Treatment in Cats with Feline Fibrosarcoma
New Bolton Center Kennett Square, PA
Emergencies & Appointments:
Ryan Hospital Philadelphia, PA

Trial of ALVAC® IL-2 Treatment in Cats with Feline Fibrosarcoma

Jun 1, 2015

The purpose of this study is to evaluate the safety and effectiveness of surgery combined with an injection of ALVAC IL-2 (feline interleukin-2) as a treatment for feline fibrosarcoma (FSA).

FSA is one of the most common cancers in cats. These tumors develop in the subcutaneous tissues and can invade extensively into the adjacent skin and muscle. Because of this, complete surgical removal can be difficult and recurrence of the tumor is common. Current standard of care treatments include various combinations of surgery, radiation, and chemotherapy.

ALVAC IL-2 is a type of immunotherapy. It is an injection designed to help a cat’s immune system to kill any cancer cells that remain following surgery.

Surgical removal of the fibrosarcoma tumor is required.  Each cat will be randomly assigned (like flipping a coin) to one of three treatment groups: low dose ALVAC IL-2, high dose ALVAC IL-2, or no ALVAC IL-2.  Each cat will be in the treatment portion of the study for 2 months and in the follow-up portion of the study for up to two years.


  • Cats with confirmed diagnosis of feline fibrosarcoma that is able to be surgically removed (not on the head, tail, or lower limbs)

  • Cats without evidence of metastasis

  • Cats not currently undergoing chemotherapy


Costs of eligibility screening and all treatments with the study medication, as well as study-related follow-up visits, are covered by the study. The study will also cover most or all of the surgical removal costs depending on the extent of surgery required.

If you are interested in participating in this clinical trial or would like to learn more about it, please contact the VCIC at 215-573-0302 or email