A Phase 2 Study Immunologically Evaluating 5T4-MVA (TroVax) in Patients Undergoing Surgical Resection of Colorectal Liver Metastases
Treatment of metastatic colorectal cancer depends on the site of disease. The prognosis for
patients is poor although cure can be obtained if disease is localised and operable.
Patients with metastatic disease confined to the liver may achieve a cure rate of between
20% and 60% if these metastases are resited, but there is a risk that micrometastatic
disease will persist post-operatively.
TroVax consists of a highly attenuated vaccinia virus (modified vaccinia Ankara) containing
the human tumour associated antigen ST4.
The human oncofetal antigen 5T4 a surface glycoprotein expressed by placental tissue, but
also by a wide range of human carcinomas including most colorectal and renal carcinomas.
5T4 exhibits only low level expression in normal tissue and is thus a suitable target for
immune therapy of cancer.
This study will evaluate for the first time in man the immunological effects of the TroVax
vaccine locally within a target tumour and in peripheral blood. Tolerability of the vaccine
will also be assessed.
Patients receive 2 intramuscular injections of TroVax at a 2 week interval followed by
surgery 10 days later. Two further vaccinations are given at 4 and 8 weeks after surgery.
Patients who show a response to the first four vaccinations are given 2 additional
vaccinations 20 and 28 weeks post surgery.
Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
To characterise and quantify the immune response to the oncofetal antigen 5T4 locally in peripheral blood, modified by vaccination with TroVax before resection of colorectal adenocarcinoma liver metastases.
Robert Hawkins, MD, Prof
Christie Hospital NHS Foundation Trust
United Kingdom: Medicines and Healthcare Products Regulatory Agency