Long-term clinical and immunological effects of p53-SLP® vaccine in patients with ovarian cancer

✍ Scribed by Ninke Leffers; Renee Vermeij; Baukje-Nynke Hoogeboom; Ute R. Schulze; Rinze Wolf; Ineke E. Hamming; Ate G. van der Zee; Kees J. Melief; Sjoerd H. van der Burg; Toos Daemen; Hans W. Nijman

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: French
• Weight: 528 KB
• Volume: 130
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.25980

✦ Synopsis

Abstract

Vaccine‐induced p53‐specific immune responses were previously reported to be associated with improved response to secondary chemotherapy in patients with small cell lung cancer. We investigated long‐term clinical and immunological effects of the p53‐synthetic long peptide (p53‐SLP®) vaccine in patients with recurrent ovarian cancer. Twenty patients were immunized with the p53‐SLP® vaccine between July 2006 and August 2007. Follow‐up information on patients was obtained. Clinical responses to secondary chemotherapy after p53‐SLP® immunizations were determined by computerized tomography and/or tumor marker levels (CA125). Disease‐specific survival was compared to a matched historical control group. Immune responses were analyzed by flow cytometry, proliferation assay, interferon gamma (IFN‐γ) ELISPOT and/or cytokine bead array. Lymphocytes cultured from skin biopsy were analyzed by flow cytometry and proliferation assay. Of 20 patients treated with the p53‐SLP® vaccine, 17 were subsequently treated with chemotherapy. Eight of these patients volunteered another blood sample. No differences in clinical response rates to secondary chemotherapy or disease‐specific survival were observed between immunized patients and historical controls (p = 0.925, resp. p = 0.601). p53‐specific proliferative responses were observed in 5/8 patients and IFN‐γ production in 2/7 patients. Lymphocytes cultured from a prior injection site showing inflammation during chemotherapy did not recognize p53‐SLP®. Thus, treatment with the p53‐SLP® vaccine does not affect responses to secondary chemotherapy or survival, although p53‐specific T‐cells do survive chemotherapy.