Inovio Pharmaceuticals, Inc announced a poster presentation of additional prostate cancer data (Abstract #229675) at the American Society of Clinical Oncology (ASCO) annual meeting to be held in Chicago, June 1-5, 2018.
Previously reported data from a phase 1b clinical trial demonstrated that Inovio’s cancer immunotherapy (INO-5150) slowed PSA rise in patients with biochemically recurrent prostate cancer. Additional analyses show clinically meaningful PSA stabilisation post-administration of Inovio’s immunotherapy in patients with no documented disease progression during the study. Of note, this effect was also observed in the patients with the fastest PSA doubling at the time of study entry.
The multi-center phase 1b study enrolled 62 patients with biochemically relapsed prostate cancer following definitive local therapy. Under the trial design, eligible patients received INO-5150 (DNA plasmids encoding prostate specific antigen (PSA) and prostate specific membrane antigen (PSMA)) alone or co-administered with INO-9012 (IL-12 plasmid) delivered intramuscularly followed by EP using the CELLECTRA-5P device. Of the 61 evaluable patients, 77% (47/61) demonstrated T cell immunogenicity, and 38% (19/50) exhibited CD38+, Perforin+CD8+ T cell responses. Additional analyses are underway to elucidate the correlation between immunologic efficacy and clinical benefit.
Dr. J. Joseph Kim, Inovio’s president & CEO, said, “The additional results from our Phase 1b INO-5150 study continue to support our rationale that Inovio’s T cell generating INO-5150 could be an important agent as an immunotherapy as it provides strong and durable immune responses in a particularly difficult-to-treat prostate cancer patient population. We remain diligent on establishing an outside partnership to further advance INO-5150 and I look forward to sharing additional observations from our prostate cancer development programme later this year.”
INO-5150 was generated using Inovio's proprietary ASPIRE technology process to enable significant production of engineered PSA and PSMA antigens with genetic sequences differentiated from native human PSA and PSMA sequences. This patented approach is designed to help the body's immune system overcome its "self-tolerance" to prostate cancer cells and mount a strong targeted CD8+ killer T cell response to eliminate the cancerous cells displaying these antigens. PSMA is also one of 3 antigens comprising INO-5401, which is being tested in two separate phase 1/2 trials as an immunotherapy to treat glioblastoma and metastatic bladder cancer in combination with Regeneron and Genentech/Roche’s checkpoint inhibitors, respectively.