IMUNON, Inc. announced positive results from its Phase 2 OVATION 2 clinical trial of IMNN-001, an investigational interleukin-12 (IL-12) immunotherapy, for advanced ovarian cancer. The study, presented at the Society for Immunotherapy of Cancer (SITC) 39th Annual Meeting, showed a significant improvement in overall survival and progression-free survival when IMNN-001 was combined with standard-of-care chemotherapy.
The OVATION 2 study enrolled 112 patients with newly diagnosed advanced ovarian cancer, randomizing them to either IMNN-001 plus neoadjuvant and adjuvant chemotherapy (NACT) or standard-of-care NACT alone. With a median follow-up of 24 months, the IMNN-001 group demonstrated a median overall survival of 40.5 months compared to 29.4 months in the NACT-only group, representing a 35% improvement (hazard ratio 0.74).
Progression-Free Survival and Surgical Outcomes
IMNN-001 also showed an improvement in progression-free survival, with a median PFS of 14.9 months compared to 11.9 months in the control group (hazard ratio 0.79). Furthermore, the surgical response rate was higher in the IMNN-001 group (64.6%) compared to the NACT-only group (52.1%). The chemotherapy response score was 26.1% in the IMNN-001 treatment group versus 13.0% in the control group.
Safety and Tolerability
Notably, IMNN-001 was generally well-tolerated. The most common adverse events were primarily gastrointestinal, such as abdominal pain, nausea, and vomiting, which were effectively managed with pain management protocols. There were no reports of cytokine release syndrome or other serious immune-related adverse events.
Impact of PARP Inhibitors
A subgroup analysis of patients who received a PARP inhibitor as maintenance therapy revealed a median PFS of 33.8 months in the IMNN-001 arm versus 22.1 months in the control arm (hazard ratio 0.80). The median overall survival was not reached for the treatment arm versus 37.1 months for the control arm.
Expert Commentary
"These results from OVATION 2, including overall survival and progression-free survival among women with advanced ovarian cancer treated with IMNN-001 and NACT compared to standard-of-care NACT alone, reflect a meaningful improvement and show consistency across various endpoints and patient subgroups," said Stacy Lindborg, Ph.D., president and chief executive officer of IMUNON. "This consistency brings great hope and excitement that these results can be replicated in Phase 3, and that IMNN-001 may offer a significant advancement in the treatment landscape for ovarian cancer."
Jennifer Scalici, M.D., Professor, Division of Gynecological Oncology, Emory University School of Medicine, added, "IMNN-001 is the first immunotherapy to achieve a clinically effective response in ovarian cancer, including benefits in both progression-free and overall survival, let alone in a first-line treatment setting. It is also especially encouraging that IMNN-001 offers benefits when used alongside PARP inhibitors... There is a significant unmet need in treating women with ovarian cancer, which is the second deadliest gynecologic malignancy, and the promising results from the OVATION 2 Study represent the potential of IMNN-001 to offer a much-needed treatment option."
Future Plans
IMUNON plans to hold an End-of-Phase 2 meeting with the FDA to discuss the design for a Phase 3 pivotal study of IMNN-001 in advanced ovarian cancer, with the trial expected to start in the first quarter of 2025.
