Virus as Viable Drug - Pharmaceutical Executive


Virus as Viable Drug
Coincidence or phenomena? The reovirus is Mother Nature's own cancer-killer.

Pharmaceutical Executive

As it turns out, that's not an issue. We've treated about 110 patients now, and half the patients have no side effects and the other half get a degree of fever, or they're tired or get muscle pain for a day. Compared to what you get with old-line chemotherapy or radiation or surgery, it's nothing. The alternatives are a lot more aggressive than not feeling up to snuff for a day or so.

What was your biggest concern with taking on such early science?

Most virus products fail, not because they don't work. Actually, virtually all of them are active. They fail because you can't make them.

It's like the Taxol problem. There weren't enough Pacific Yew trees in the world to generate enough Taxol to treat patients. It worked, but until they had a synthetic process to make Taxol in bulk, it had no future as a product. But now we know how to produce it.

Oncoloytics' Phase I clinical program lasted for three years. Why so long?

For two reasons. The product is so active that we needed a more comprehensive understanding of its activity in a Phase I environment. We've seen clinical responses in patients with prostate, breast, lung, liver, head and neck, esophageal, melanoma, and pancreatic cancers. That has given us a lot of confidence going into Phase II. Secondly, we wanted to show, above and beyond, that it was safe.

We also wrestled with the issue of staged timing. That's where in Phase I, you infect somebody with the virus, and then you wait a period of time to ensure that there's no safety issues before you move to the next patient cohort.

We don't want a repeat of the TeGenero study last spring in the United Kingdom, where they treated six patients in the same hour in the same room, and had the placebo patients watch the treated patients all inflate like little balloons and almost die in front of their eyes. That would never happen on a reovirus study because we properly space the dosing of patients.

Our radiation study [which treated patients in combination with Reolysin] was approved about six weeks after that whole issue blew up in the United Kingdom. The Medicines and Healthcare Products Regulatory Agency just sent it back and said, "It's approved" —and that's when they were in the middle of the firestorm of answering the question "Was it your fault?" That's because we do things the way they want us to and the way it's supposed to be done. That's why it has been slow.

How safe is this approach?

There's probably 6,000 or 7,000 patients that have been treated with gene therapy for oncology or virology, but there's been less than 10 serious adverse events. And they're usually patients who shouldn't have been in the study in the first place.

The bubble kids in France should not have gotten gene therapy, period. We know that now. Jesse Gelsinger [who died at the University of Pennsylvania in 1999 after receiving gene therapy] should not have been enrolled in that study with adenoviruses because he had a liver issue, and adenoviruses are liver toxic.

So the serious adverse events are explainable, but it's the lowest serious side effect profile of any new drug class ever with that many patients.

The reovirus is, in essence, a platform drug. How do you decide which indication to go after?

Until now, we've been positioned as the "two-thirds of all human cancers company." But this year, Oncolytics will run eight Phase II studies of different drug and radiation combinations to identify specific cancers to go after.


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