Medical Device Daily National Editor

James Bond lies tied down, legs spread, a laser pointed at his nether regions (remember that scene from "Goldfinger"?).

That disturbing image just might pop into the mind of a prostate cancer patient, when told of the therapy being developed by Steba Biotech (New York), a company using laser technology for activation of a material for killing prostate cancer cells.

Not to worry, assures CEO Douglas Altschuler, the laser energy Steba uses is extremely low-level, more like "activated light," and delivered much like standard brachytherapy treatment of the prostate – thus a life-saver rather than an instrument of torture.

Key to the strategy is the use of a photosensitizer which, when activated by light, occludes the blood vessels that feed a tumor. Close down these vessels and you kill the tumor, is Steba's theory, and an alternative to directly attacking the tumor itself with surgery, chemotherapy or the use of radiation.

While the company's strategy is a standard phototherapeutic method, the key is the use of a non-standard material — rather than activation of a prodrug — to provide the vessel-killing effect.

Steba is using a material called WST11, which it describes as a photosensitizer. WST11 is a derivative of natural bacteriochlorophy, developed in a collaborative effort between Steba, Negma Lerads (Paris), and the Weizmann Institute of Science (Rehovot, Israel). The material is licensed by Steba from Weizmann.

Steba notes that the vascular-occluding effects of photodynamic therapy have been known for some time, and with the potential for treating tumors. But it says that the previous attempts to destroy tumors via vascular destruction had been less than optimal because various photosensitizers remained in the cells of normal tissue, causing prolonged toxicity.

By contrast, WST11 clears from the body entirely in just 30 minutes, Altschuler told MDD.

The material, he said, is derived from "a chlorophyll that is generated by bacteria which grows in the dark ... it does not need sun. We take it to our facility in Israel, modify it and stabilize it." He said this material is "neutral, non-toxic," and termed the overall approach "green biology."

After injection into the tumor cite, the material is activated by laser light. Developed in collaboration with Israeli laser firm Egen (Tel Aviv), the laser is extremely low-powered, Altschuler noted, and "is as much of a computer as a laser. It measures the light power within the tumor, and uses a feedback loop and shuts off, and reports all the information about the procedure."

The activating light is delivered by fibers inserted near the prostate, in much the same way as the delivery of brachytherapy, then removed. And the company will market the technology only to those already providing brachytherapy, Altschuler said, so that the required training will be minimal.

When activated by the laser light, the material serves to occlude the blood vessels, turns them "necrotic,' and leaves, under MR imaging, only "a black hole," he said.

Importantly, the technique exploits the difference between blood vessels within a cancerous tumor, and blood vessels within normal tissue, he noted.

The company currently is conducting a multi-center, dose-ranging trial at five sites, one in Canada and four in Europe and the UK, with enrollment of 40 patients. It is developing additional sites throughout Europe for this trial and will follow up with a smaller dose-ranging trial in Europe.

The next step is pursuit of a Phase II trial in the U.S.

Altschuler said the company soon will be talking to the FDA to develop the protocols for this trial, and he acknowledged that a key challenge will be to get the agency "to understand what kind of trial we need to do – nothing like this has ever been done before." But he said that the company hopes these protocols can be worked out so that the U.S. trial can be launched this summer.

To date, Steba reports procedures performed on somewhat more than a dozen men and said it is "quite pleased with the early signals of efficacy." It also reported being in the "early stages" of preparation to report its data.

Altschuler said that the company is "completely, privately self-funded," and able to draw on €130 million to pursue the development of the application for prostate cancer.

He spoke yesterday to MDD on his way to the airport to talk to investors in Los Angeles, but said any potential funds developed from here on out are intended to be used for the company's development of its next-generation application, the treatment of macular degeneration.

He noted that a good bit of photodynamic therapy had been used for treatment of macular degeneration but that this approach was quickly swamped by new drug treatments, particular the use of Lucentis, now standard therapy.

But he said that Lucentis treatments are too frequent and eventually fail.

Steba plans to use its photodynamic therapy strategy in combination with drug treatment to provide equal or better outcomes and with fewer treatments.

Atlschuler acknowledged he can't predict a timeline for commercialization of the prostate therapy application, but said that the company clearly prefers a "two-to-three-year window," rather than one of five to six years.

With an already established career in device development and photodynamic therapies, Altschuler understated by saying he sees Steba's technology as a potential winner – adding: "I have a nose for these things."

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