14 June 2019 - - Canadian immuno-oncology corporation IMV Inc. (NASDAQ: IMV) (TSX: IMV) has released updated data from the ongoing investigator-sponsored SPiReL Phase 2 clinical trial assessing IMV's lead candidate, DPX-Survivac, in combination with intermittent low dose cyclophosphamide and US Merck's checkpoint inhibitor Keytruda (pembrolizumab), the company said.
The trial is designed to evaluate the safety and efficacy of the combination immunotherapy in patients with persistent or recurrent/refractory diffuse large B-cell lymphoma (DLBCL).
At the first "on treatment" assessment, five of the first six patients demonstrated clinical benefit, including four patients with tumor regressions.
Two patients reached a complete radiological response, one a partial response, and two had stable disease while on study. In addition, the combination continued to demonstrate an acceptable safety profile.
At the time of data cut-off for this analysis, 11 patients were enrolled in the trial. Efficacy data from the first six evaluable patients are based on modified Cheson criteriai.
Two patients achieved a complete radiological response. These patients have shown the best survivin specific T cell responses to DPX-Survivac among the analysed samples.
One patient with a Complete Response has completed the one-year study period. One patient achieved a Partial Response at first "on treatment" scan. Two patients have reached stable disease. Each of these patients has remained progression free for six and eight months while on treatment. One patient with bulky disease progressed at first scan.
Two subjects are not evaluable, coming off trial at day 7 and day 28. The treatment combination appears to be well-tolerated with only 2 serious adverse events related to treatment (low white blood count and low neutrophil count). Radiological results from three additional patients are pending.
The ICML abstract was published on June 12, 2019 via the 15-ICML ABSTRACT BOOK, a supplement to Hematological Oncology with first author Neil Berinstein, MD, FRCPC, ABIM Haematologist at the Odette Cancer Centre, Sunnybrook Health Sciences Centre and Affiliate Scientist at Sunnybrook Research Institute. Dr. Berinstein will be available at the ICML conference to discuss the results.
Diffuse large B-cell lymphoma (DLBCL) is the most frequent type of malignant lymphoma worldwide and accounts for approximately one third of all non-Hodgkin lymphomas.
In the United States, it is estimated that nearly 25,000 new cases of DLBCL will be diagnosed in 2019.
As many as 30% of all patients with DLBCL who either fail to respond to or show a relapse to initial therapies are reported to have a poor outcome and require more therapeutic options.
SPiReL (DPX-Survivac with Low Dose Cyclophosphamide administered with Pembrolizumab in Patients with persistent or Recurrent/refractory Diffuse Large B-Cell Lymphoma) is a Phase 2 non-randomized, multi-centre, open-label study.
Primary Investigator Dr. Neil Berinstein is leading the trial, which is expected to enroll 25 evaluable participants whose recurrent DLBCL expresses survivin, a tumor antigen expressed in of the majority of DLBCL tumors.
The study's primary endpoint is to document the objective response rate. Secondary objectives include measuring tumor regression and documenting the toxicity profile and durations of response.
In addition, investigators will perform analyses to assess circulating antigen specific immune responses and changes in tumor-infiltrating T cell immune responses within the tumor microenvironment. They also plan to assess potential biomarkers of immune and clinical response.
DPX-Survivac is the lead candidate in IMV's new class of immunotherapies that programs targeted T cells in vivo. It has demonstrated the potential for industry-leading targeted, persistent, and durable T cell activation.
IMV believes this mechanism of action is key to generating durable solid tumor regressions. DPX-Survivac consists of survivin-based peptides formulated in IMV's proprietary DPX drug delivery platform. DPX-Survivac is designed to work by eliciting a cytotoxic T cell immune response against cancer cells presenting survivin peptides on their surface.
Survivin, recognized by the National Cancer Institute (NCI) as a promising tumor-associated antigen, is broadly over-expressed in most cancer types, and plays an essential role in antagonizing cell death, supporting tumor-associated angiogenesis, and promoting resistance to anti-cancer therapies. 
IMV has identified over 15 cancer indications in which the over-expression of survivin can be targeted by DPX-Survivac.
The US Food and Drug Administration (FDA) has provided Fast Track designation to DPX-Survivac as maintenance therapy in advanced ovarian cancer. In addition, the FDA and European Medicines Agency (EMA) have granted orphan drug designation status in the ovarian cancer indication.
Investigators are currently evaluating DPX-Survivac in multiple Phase 2 clinical trials.
IMV is a clinical stage biopharmaceutical company dedicated to making immunotherapy more effective, more broadly applicable, and more widely available to people facing cancer and other serious diseases. IMV is pioneering a new class of immunotherapies based on the company's proprietary drug delivery platform.
This patented technology leverages a novel mechanism of action that enables the programming of immune cells in vivo, which are aimed at generating powerful new synthetic therapeutic capabilities.
IMV's lead candidate, DPX-Survivac, is a T cell-activating immunotherapy that combines the utility of the platform with a target: survivin. IMV is currently assessing DPX-Survivac as a monotherapy in advanced ovarian cancer, as well as a combination therapy in multiple clinical studies with Merck.