An experimental gene therapy using a genetically engineered cold virus is being studied as a treatment approach for recurrent glioblastoma.
Article Highlights
- Following surgical resection, a viral vector strategy using a modified common cold virus delivers herpes simplex virus DNA selectively to dividing tumor cells (i.e., glioblastoma cells). Subsequent administration of valacyclovir induces targeted cytotoxicity, achieving an immediate tumor cell kill followed by a sustained, immune-mediated secondary response.
- The described protocol demonstrates prolonged oncologic effect, with continued tumor cell death observed over multiple years in responsive patients. In this case, serial imaging showed progressive and sustained tumor regression post-intervention, highlighting the potential for durable control in an otherwise rapidly recurrent glioblastoma.
- The patient presented with aggressive disease progression and had been given a limited life expectancy following recurrence after prior surgical intervention. Implementation of this advanced therapeutic approach resulted in a markedly improved clinical trajectory, underscoring its relevance for patients with limited standard-of-care options and the importance of expanding access to investigational therapies.
Despite being told his glioblastoma had resisted treatment and grown back, that he had only weeks to live, 16-year-old Alex Gross wasn't ready to give up.
Gross' family heard the story of Ed McCumber, a fellow Myrtle Beach resident whose aggressive glioblastoma was successfully conquered with an experimental gene therapy developed at Houston Methodist.
The family traveled to Houston so Alex could see the neurosurgeon who treated McCumber's brain cancer — Dr. David Baskin, director of the Kenneth R. Peak Brain and Pituitary Treatment & Research Center at Houston Methodist.
After surgically removing Alex's tumor, Dr. Baskin and his team administered the therapy, an injection of a genetically engineered cold virus that that attacks the remaining cancer cells.
"When you're doing research with something this powerful, you can't find out how effective something is unless you're constantly pushing the envelope," says Dr. Baskin.
In the video above, he explains how this novel cancer gene therapy works and what Alex's case taught him.
Transcript
00:00–00:30
Alex had headaches for about two years. And the doctor had told us that it was puberty. No one ever suggested to get an MRI to see what was going on. He had just started learning how to drive. He was behind the wheel, and he had said that he couldn't feel his arms and legs.
00:30–01:00
So from that point on, everything just kind of went downhill. He had three seizures within an hour. He was unresponsive for almost 32 hours. It feels absolutely surreal, like you're in a movie. Somebody else wrote the script. You have no choice but to play it out. Then he had a minor surgery here. They took a biopsy. And they basically told us that he had glioblastoma.
01:00–01:30
He has a tumor that starts on one side of his temporal lobe, goes all the way to the back of the brain, and then crosses to the other side. He was operated elsewhere at a very good institution. The tumor grew back rapidly. And he was told really that he had weeks to live. So my dad actually found Dr. Baskin on one of the YouTube videos.
01:30–02:00
And he found a man named Ed that lived here in Myrtle Beach. I told my dad that if this man was really real that he needed to go find him. And they actually went to visit my patient Mr. McCumber at his workplace because they couldn't believe that it was real. And there he was, back at work, with successful gene therapy. Talked to him and said, listen, we need to come here. So they reached out to me.
02:00–02:30
We went down there and talked. And Dr. Baskin gave us our options. And he talked to me, it seemed like forever, and basically went over everything and what could happen, what might happen, just like everything that you could possibly imagine. After we remove the tumor, we inject a virus, which is a common cold virus. The virus is taken up only by dividing cells, which, in the brain, is the tumor cells.
02:30–03:00
Inside this cold virus, we put a tiny piece of herpes virus DNA. The virus spreads into the fingers very rapidly. We use 500 billion viral particles, the highest dose anywhere in the world. And then 24 hours later, you take a drug called Valtrex, which is a drug for herpes cold sores. The Valtrex recognizes that piece of DNA and kills every cell with the virus in it, which are the tumor cells. So you get an immediate huge kill.
03:00–03:30
And then as those tumor cells die, the virus is engineered to make an immune response. So you get a second wave of antibodies and cells that come in and continue to kill the tumor cells. And in fact, in our successful patients, we've seen brain cancer cells die for five years. So we did the surgery. Surgery went well. And most remarkably, month after month after month, the tumor's going away and going away and going away and going away.
03:30–04:00
And his scan now looks unbelievably good. I think that one of the things this case has taught me is that never give up. Never say no. Try to push the boundaries as much as you can. Because when you're doing research with something this powerful, you can't find out how effective something is unless you're constantly pushing the envelope.
04:00–04:30
So rather than deny people who are on the edge treatment we want to reach out, include them. And that's what we did here. And so far, we have an absolutely amazing result. I got the opportunity to spread the word about how great it is to save a life. And it feels cool!