Up to 70% of patients with metastatic colorectal cancer who have surgery to remove the tumors have a recurrence within two years. What if there was a way to not only treat the metastases, but also prevent the cancer from coming back?

The liver is one of the most common sites for metastases from gastrointestinal cancers, especially colorectal cancer. The Hepatobiliary Section in the Gastrointestinal Oncology Program at Moffitt Cancer Center has launched a clinical trial to determine if injecting an oncolytic virus into one liver metastasis prior to surgery can stimulate the body’s immune system to attack not only the tumor that was injected, but also other tumors.

The first-of-its-kind phase 1 trial will study the safety of using the vaccine in patients who are undergoing surgery to remove liver metastases. Additionally, the trial will look at the body’s immune response against cancer cells after virus injection.

“One of the unique things about this trial is that since it is being offered to patients who are being treated for a cure, the tumors will be removed as part of the standard treatment for cancer,” said Dr. Daniel Anaya, a hepatobiliary surgeon and trial principal investigator. “This will allow our team to examine all resected tumors—the one injected with the virus, as well as other non-injected tumors.”

Patients enrolled in the trial will receive two injections of a genetically modified adenovirus vaccine—DNX-2440 made by DNAtrix—one 28 days prior to surgery and one 14 days before surgery. Blood and tissue samples will also be taken before, during and after the injections to collect as much data as possible to better study the vaccine and launch correlative studies.

The trial will also be testing the abscopal effect, a hypothesis that injecting only one tumor with localized treatment can also concurrently shrink untreated tumors.

“The virus is injected into the tumor, so it infects the cancer cells and induces an immune response against that tumor,” said Anaya. “But since the tumor’s cancer cells are also in other liver lesions that don’t get injected, we are hoping we can not only generate an immune response at the injected lesion, but against all the other lesions too.”

The trial will enroll between 24 and 30 patients. If the trial is successful, future, larger studies would be done, as this therapy has the potential to be used in the treatment of metastatic cancer or to prevent disease recurrence in patients after surgery.

“The ultimate goal of this therapy is to stimulate an immune response against the cancer cells in the body, in both injected and non-injected tumors – kind of like a vaccine would do,” said Anaya.