First Patient Dosed in Phase 2 Trial Evaluating Ampligen-Keytruda-Chemo Combo for Ovarian Cancer

The first patient has been dosed with Hemispherx Biopharma‘s experimental treatment Ampligen (rintatolimod), in combination with Keytruda (pembrolizumab) and cisplatin, for recurrent ovarian cancer.

The investigator-sponsored Phase 2 trial (NCT03734692) is expected to treat 45 ovarian cancer patients who responded to platinum-based chemotherapy for at least six months. It is taking place at the University of Pittsburgh School of Medicine in Pittsburgh, Pennsylvania, and is still recruiting participants.

The trial aims to test the safety and efficacy of the triple combination. Its primary goal is to determine the number of patients achieving at least a 30% reduction in tumor size.

Ampligen — approved in Argentina for severe cases of chronic fatigue syndrome — is an immune modulator that activates specific immune cells and is expected to increase the number of immune cells infiltrating the tumor.

Hemispherx is testing the intraperitoneal (into the abdomen) administration of Ampligen in a Phase 1/2 trial (NCT02432378). The trial’s preliminary results showed that Ampligen could reprogram the tumor’s microenvironment by accumulating killer T-cells — immune cells that attack cancer cells — without increasing the number of regulatory T-cells (Tregs) that suppress the immune response.

“Our initial study indicates that Ampligen is generally well-tolerated via intraperitoneal administration, thus paving the way for this new Phase 2 study combining Ampligen and [Keytruda] pembrolizumab,” Robert Edwards, MD, director of the ovarian cancer program at UPMC Magee-Women’s Hospital and principal investigator of the trial, said in a press release.

“Ampligen has the potential to be clinically significant because a robust killer T-cell population in the tumor microenvironment without attracting Treg cells is important to help optimize checkpoint blockade induced tumor shrinkage,” he added.

The idea behind combining anti-cancer agents is to accomplish a synergistic effect that improves the fight against tumors. In preclinical animal studies, Ampligen has shown a synergic effect when combined with other treatments.

Keytruda is an immunotherapy used to treat various types of cancer. The treatment increases the immune response against tumors by specifically binding a receptor present on the surface of immune cells, thus preventing cancer cells from silencing immune cells produced to attack them.

Hemispherx expects that the combination of Keytruda and Ampligen will improve the anti-cancer response of both treatments by providing a scenario where more immune cells ready to fight cancer are recruited to the tumor. Because ovarian cancer responds well to platinum chemotherapy, the two agents will be tested in combination with cisplatin.

“This year, worldwide, ovarian cancer is projected to kill 152,000 women. With this new large-scale study funded by an industry grant, Hemispherx and the team at Magee-Women’s Hospital of the University of Pittsburgh School of Medicine are focused on developing a potentially life-saving therapy to meet this critical and unmet medical need,” said Thomas K. Equels, CEO of Hemispherx.