Immunovaccine a clinical stage vaccine company, announced that new positive clinical data on the company’s lead cancer vaccine candidate, DPX-Survivac, will be presented as a poster at the 2014 ASCO Annual Meeting in Chicago, Illinois from May 30 to June 3.

Results presented from the Phase I/Ib clinical study demonstrate promising early evidence of clinical activity for DPX-Survivac in ovarian cancer patients, including one patient who experienced a partial response (PR). The PR, defined as a shrinking of tumour size by at least 30 per cent using Response Evaluation Criteria In Solid Tumours (RECIST 1.1), was accompanied by reduction in levels of a commonly used ovarian cancer biomarker (CA125) and a significant increase in vaccine-induced immune responses.

The abstract, “Phase I/Ib Clinical and Immunologic Assessment of Immunotherapeutic Vaccine, DPX-Survivac in Women with Ovarian, Fallopian Tube, of Peritoneal Cancer (OC),” will be presented during the General Poster Session, Gynecologic Cancer, Saturday, May 31, 2014.

One study patient with residual disease following platinum therapy experienced a PR which correlated with robust immune responses to DPX-Survivac.  The PR persisted following discontinuation of the treatment.

Target immune responses were seen across all doses and when DPX-Survivac was administered alone or with low dose oral cyclophosphamide (CPA). Statistically significant increases in immune response were seen with higher doses of DPX-Survivac and when DPX-Survivac was combined with CPA.

DPX-Survivac was well tolerated with no significant systemic adverse events reported

“The durable clinical response highlights the therapeutic potential of DPX-Survivac,” stated Dr. Marc Mansour, chief operating officer of Immunovaccine.  “To our knowledge, the target immune responses induced by our vaccine approach are among the strongest of any published immune results in the cancer immunotherapy field.”

In April, Immunovaccine presented positive data from clinical and preclinical vaccine studies, including DPX-Survivac, at the American Association for Cancer Research (AACR) 2014 Annual Meeting.  Results demonstrated that metronomic cyclophosphamide (mCPA), an immune modulating agent, enhanced the immunogenicity of DepoVax-based vaccines in preclinical cancer models consistent with previously reported Phase I data showing a similar enhancement of DPX-Survivac in patients. Importantly, the animal studies demonstrated the combination therapy’s ability to eliminate advanced tumours that could not be treated with vaccine or mCPA alone. The addition of anti-PD-1 checkpoint inhibitor to the DepoVax vaccine/mCPA combination resulted in further enhanced anti-tumour activity, which allowed the treatment of more advanced tumours. The effective tumour regressions that were observed could not be achieved without the use of vaccine or the use of anti-PD-1.   

Immunovaccine expects a large randomised Phase II trial of DPX-Survivac to be initiated in 2014 in ovarian cancer. The 250 patient trial will be sponsored and conducted by Canada’s NCIC Clinical Trials Group (NCIC CTG).  Additionally, researchers at the University of Rome are planning to initiate a Phase l/II trial of DPX-Survivac in glioblastoma (brain cancer) with the first patient receiving the vaccine in 2014.