The doctor checks the magnetic resonance examination and looks for a brain tumor or stroke in the patient.

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John Wishman was diagnosed with the deadliest form of brain cancer, glioblastomain autumn 2020.

Two and a half years later, she is still traveling and enjoying life – a rarity in cancer with an average survival time of just 12 to 18 months.

Wishman, 61, of Buffalo, New York, attributes that to an experimental vaccine designed to slow the tumor’s progression. The vaccine, called SurVaxM, targets a protein found in tumors called survivin, named for the role it is thought to play in cancer cell survival. Get rid of survivin, they say, and cancer cells die.

It sounds like a pipe dream: a vaccine that can delay the return of glioblastoma one of the deadliest and treatment-resistant cancers. More than 14,000 people in the U.S. were diagnosed last year, according to Tom Halkin, a spokesman National Brain Tumor Society, a non-profit group. It accounts for almost half of all malignant brain tumors. The disease is devastating to patients and families; five-year survival is 6.8%.

Wishman obtained the vaccine through the expanded access program—sometimes called compassionate use — which allows seriously ill patients to gain access to experimental drugs. His daughter, Lydia, is a nurse at Roswell Park Comprehensive Cancer Center, where researchers are studying the drug.

In an early clinical trial, SurVaxM was found to prolong survival in people diagnosed brain cancer on average up to 26 months. Now the drug’s maker, New York-based MimiVax, is enrolling patients in a larger study in hopes of confirming the results. The Extended Access Program is no longer available.

Up to 270 patients will be included in the new study. It is expected to occur at more than 10 sites in the US and China and will compare the image with patients receiving standard care.

Tracey Kassman, 65, signed up in April 2022, three months after she was diagnosed with glioblastoma. She got her first shot that same month.

Kassman, a retired attorney from Buffalo, now gets a shot every two months. But because the trial is randomized and double-blind, Kassman and her doctors don’t know whether she’s getting the vaccine or a placebo.

“It’s been a leap of faith at times,” she said, “because right before I get an injection, I have this MRI, and every time I have an MRI, I’m like, ‘Okay, this could be it.'”

Why is glioblastoma so difficult to treat?

Glioblastomas are aggressive cancers: They grow quickly and tend to invade other parts of the brain and spinal cord by the time a person is diagnosed.

Surgical removal of the entire tumor is almost impossible.

“It’s like the tentacles of an octopus reaching into other parts of the brain,” said Honggang Cui, associate professor of chemical and biomolecular engineering at the Johns Hopkins Whiting School of Engineering.

Treatment usually includes surgery, chemotherapy and radiation, Cui said. But if all the cancer cells are not removed, the tumor often comes back in a form called recurrence.

SurVaxM works by training the immune system to target and attack cancer cells, so if they return, the body can pick them up and prevent a new tumor from growing, said Michael Ciesielski, CEO of MimiVax.

The approach is “promising,” Cui said. “This could bring hope to people affected by GBM.”

Study participants will first undergo surgery to remove as much of the tumor as possible, followed by radiation and chemotherapy with a drug called temozolomide, said Dr. Robert Fenstermaker, chairman of the neurosurgery department at Roswell Park Comprehensive Cancer Center and co-creator of SurVaxM.

“Usually there’s a pause of about a month while the radiation is still working, and it’s during this phase that we like to start vaccinations because that’s when the immune system is rejuvenated,” he said.

Vaccine — given in the arm just like a flu shot or Covid shot — consists of four doses spread over two months, followed by a booster dose every two months. Study participants will receive either the real vaccine for each injection or a placebo injection each time. Participants will also receive a brain scan every two months to monitor signs of progression.

The need for different approaches

SurVaxM is not the first attempt to create a vaccine that can be delayed recurrence of glioblastoma. other cancer vaccines have targeted survivin, but none have yet reached mid- to late-stage clinical trials, Ciesielski reports.

Dr. Alyx Porter, a neuro-oncologist at the Mayo Clinic in Phoenix, said this approach is different from what has been tried in the past.

Targeted therapies such as checkpoint inhibitorshave gained popularity in recent years, e.g. improving survival in people with cancer, including those with breast or lung cancer. But these drugs are much less effective in brain tumors because they cannot cross the blood-brain barrier, a network of blood vessels that prevents foreign substances from entering the brain.

Porter said the belief is that antibodies generated by the vaccine could travel to the brain. But she added, “the proof will be in the pudding in court.”

Results are still a long way off: According to Ciesielski, the company doesn’t expect its first results from the Phase 2b study until mid-2024, and the trial likely won’t be completed for another 18 to 24 months after that. If successful, the company will need to conduct a larger Phase 3 clinical trial.

The high mortality rate of glioblastoma “warrants people to push the edge and look for new treatments and allows us to really maximize where immunotherapy can benefit,” said Porter, who is not involved in the SurVaxM study.

So far, the drug appears to be safe, Fenstermaker said. Known side effects of the vaccine include fever, itching, redness and muscle aches.

Ciesielski said the company also plans to use the vaccine for other forms of cancer, including multiple myeloma and neuroendocrine tumors, a rare form of cancer that can develop anywhere there are neuroendocrine cells found in various organs including the lungs, pancreas and gastrointestinal tract.

For Kassman, of Buffalo, New York, she feels “incredibly lucky” to have a chance at a possible treatment.

“I could ignore the whole thing again for a few weeks,” she said, “and I might not be here to talk to you about it.”

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