Adding oregovomab to standard chemotherapy significantly increases the time it takes for a newly diagnosed advanced ovarian cancer patient to have their disease progress or die, according to a Phase 3 clinical trial.
OncoQuest, which developed oregovomab, will report the preliminary results of the trial at the American Society of Clinical Oncology meeting in Chicago next month. Its poster-session presentation on June 3 will be titled “A randomized phase II study assessing an optimized schedule of oregovomab (O) anti-CA125 vaccination with carboplatin paclitaxel (CP) relative to CP alone in front-line treatment of optimally cytoreduced stage III/IV ovarian cancer (EOC).”
Oregovomab is an antibody that fights CA125, a protein expressed at the surface of ovarian cancer cells. By targeting the protein, oregovomab helps immune cells recognize and attack cancer cells.
“We are pleased to share these initial results from our phase 2 study evaluating our lead drug, oregovomab, an anti-CA125 murine monoclonal antibody in scheduled combination with standard of care chemotherapy (carboplatin and paclitaxel) compared to standard of care alone in ovarian cancer patients in the front-line or initial treatment setting,” Madi Madiyalakan, OncoQuest’s CEO, said in a news release.
The trial (NCT01616303) included 95 patients from eight centers in Italy and five in the United States. Forty-six patients treated with oregovomab and chemo had significant longer periods of disease-progression-free survival and overall survival than 49 patients treated with chemo alone.
In addition, 65 percent of those who received chemo alone had their cancer recur or died, compared with 36 percent in the oregovomab and chemo group.
Four or 8.7 percent of the oregovomab-treated patients died during the 26-month follow-up period, a quarter of the 16 or 32.7 percent who died in the chemo-alone group.
Further analysis showed that patients with a more aggressive ovarian cancer — stage IIIC or IV– benefited the most from oregovomab.
Oregovomab was well-tolerated. Both arms of the study had similar rates of side effects.
“Findings from this randomized controlled study are very encouraging and of medical significance,” Madiyalakan said. “The performance of the standard of care group is consistent with expectation, but the combinatorial immunotherapy arm has significant improvements for both relapse and survival relative to that standard.
“The company is using what we have learned in this trial to advance oregovomab in two additional Phase 2 studies in treatment-resistant, recurrent disease settings of ovarian cancer,” Christopher Nicodemus, chairman of OncoQuest’s Clinical Advisory Board, said. One of the studies will involve oregovomab “in combination with a checkpoint inhibitor, Nivolumab, and the other in combination with a TLR3 agonist, Hiltonol.”
OncoQuest also has announced the start of the ORION-01 Phase 1/2 trial (NCT03100006) to evaluate the safety and effectiveness of a combination of vaccination with oregovomab and treatment with Opdivo.
The trial will cover ovarian cancer patients whose disease progressed after two or more prior lines of chemotherapy. Participants are currently being enrolled for the study at the National Cancer Centre in Singapore.