Oxford BioMedica Announces Publication of TroVax® Phase II Analyses in Peer-Reviewed Medical Journal

28 July 2013

— Results from Phase II trial in prostate cancer published in Cancer Immunology, Immunotherapy —

— Favourable tolerability and biomarker results —

Oxford, UK – 29 July 2013: Oxford BioMedica (“Oxford BioMedica” or “the Company”) (LSE: OXB), the leading gene-based biopharmaceutical company, today announces that analyses of a TroVax® Phase II study in patients with castration-resistant prostate cancer (CRPC) have been accepted for publication in the peer-reviewed medical journal Cancer Immunology, Immunotherapy, the official journal of the Association for Cancer Immunotherapy.

TroVax® (MVA-5T4) is a therapeutic cancer vaccine designed to stimulate the immune system to destroy cancerous cells expressing the 5T4 tumour antigen, which is broadly distributed throughout a wide range of solid tumours.  The paper, entitled “Vaccination of castration-resistant prostate cancer patients with TroVax (MVA-5T4) in combination with docetaxel: a randomized phase II trial” will be published in Cancer Immunology, Immunotherapy later this year.  Previews of the clinical manuscript can be accessed online at: https://link.springer.com/article/10.1007%2Fs00262-013-1457-z

The randomised, open-label Phase II study in the United States aimed to assess the activity of TroVax® plus chemotherapy drug docetaxel (Taxotere®) versus docetaxel alone.  With an initial target enrolment of 80 patients, recruitment was challenging and the study enrolled 25 patients with metastatic CRPC; 12 were treated with TroVax® plus docetaxel and 13 were treated with docetaxel alone.  In October 2012, Oxford BioMedica made a strategic decision to close the US trial in order to focus on investigator-led Phase II studies.

Highlights from the Phase II CRPC study
• TroVax® was well-tolerated in all patients.
• Patients treated with TroVax® plus docetaxel showed a greater median progression-free survival of 9.67 months compared with 5.10 months for patients on the docetaxel alone arm (P = 0.097; HR = 0.31; 95 % CI 0.08-1.24)1.
• Importantly, a pre-treatment biomarker previously demonstrated to predict 5T4 immune response and treatment benefit showed a strong association with 5T4 antibody response and a statistically significant association with progression-free survival in patients treated with TroVax® plus docetaxel, but not docetaxel alone.
• The results demonstrate, for the first time, the prospective validation of a pre-treatment biomarker2 which is predictive of both 5T4 immune response and treatment benefit in cancer patients.

1. P = p-value, HR = hazard ratio, CI = confidence interval.
2. The biomarker is a combination of three pre-treatment blood parameters: 5T4 antibody levels; haemoglobin; and haematocrit (proportion of blood volume occupied by red blood cells) which can all be measured using a simple blood test. The biomarker is being used in ongoing investigator-led Phase II studies.

John Dawson, Chief Executive Officer of Oxford BioMedica, said: “Oxford BioMedica has a strong track record of publishing articles in well-respected medical journals. Peer-reviewed by experts, this paper demonstrates that our novel biomarker can identify patients most likely to benefit from treatment with TroVax®. The use of biomarkers in cancer immunotherapy is becoming increasingly important, which further underlines the attractiveness of TroVax® as a cancer vaccine.”