The CVac™ is a cancer vaccine product consists of an adjuvant, mannan, attached to a tumour cell surface protein, mucin 1. The product is known as MFP or mannan fusion protein. The treatment is patient-specific and delivered to patients via autologous dendritic cell therapy. The patient's dendritic cells are isolated from their blood after which MFP is mixed with the cells so as to introduce the protein mucin-1 into and expressed on the surface of the cells. 

A successful phase I trial was completed which examined the safety of the product in patients with various adenocarcinomas. All patients produced an immune response to the product. Recruitment of 28 patients for a phase IIa clinical trial to determine clinical activity in ovarian cancer has been completed and in May 2006 Prima announced evidence of clinical activity in response to CVac™ therapy. The second trial was completed by the end of 2006 and final results reported on the 14 March 2007. 

A third trial is to be conducted under the guise of the US FDA and a fourth trial under the EMEA

CVac™ demonstrated a positive clinical response or stabilisation of disease in four of the twenty-one patients based on changes in CA125.

Ovarian cancer is one of the most common malignancies and causes of cancer death in women. Standard management of ovarian cancer involves surgery followed by chemotherapy. There is a clear need to develop novel approaches to treatment in order to increase the survival of patients. The CVac™ cancer vaccine approach stimulates the patient's own immune system to target and destroy tumours.