Zap cancer, spare healthy tissue

Calypso Medical Technologies has gotten the green light from the U.S. Food and Drug Administration to sell its first creation, a tiny implanted device that can make sure radiation treatment for prostate cancer only zaps the prostate, and not a patient's surrounding healthy tissues.

The privately held Seattle company has spent seven years on research and development and more than $80 million in venture capital to get to this point. Chief executive Eric Meier said the company plans to start selling the device in the fourth quarter, and will release full results from a 40-patient clinical trial at a medical meeting in November.

The 90-employee company plans to manufacture the system entirely in-house at its Belltown headquarters, and soon will start hiring its own sales force to call on the nation's 2,000 radiation clinics, Meier said.

For now, the company won't discuss what the system will cost, or whether Medicare and other insurers are willing to pay for it.

The problem Calypso is trying to solve is vast. Prostate cancer, which afflicts 234,000 American men each year, is commonly treated with radiation. Technicians currently use CT scans to take a snapshot of the prostate, and tattoos are placed on the skin to properly line up the radiation beam. The problem is that beams often miss the tumor, hitting the bladder and other tissues, causing side effects such as impotence and incontinence.

One reason for the misses: As patients lie on a table for 20 minutes, urine can build up in the bladder and gas can build up in the rectum, pushing the prostate and making it a moving target. Sometimes patients also just have a hard time lying still for that long.

To solve the problem, Calypso has developed what doctors say is the first system that can precisely — and continuously — monitor where the prostate is, while radiation beams do their job. Calypso's device uses several implanted transponders, the size of a grain of rice, which bounce a radio signal back to a base receiver. A touch-screen monitor plots 3-D coordinates of the prostate.

If the radiology technician sees the prostate has moved out of the radiation path, he or she can shut off the beam and adjust it to the new location before any healthy tissue gets damaged.

Calypso likens its device to Global Positioning Systems — and has trademarked the phrase "GPS for the body" for marketing purposes. The company believes its system also could be used for guiding radiation against all sorts of moving tumors in the lungs, liver, pancreas, breast and other parts of the body.

Dr. Parag Parikh, a radiation oncologist at Washington University in St. Louis who has done some technical work for Calypso, said the procedure could significantly change the field. He said he is currently pursuing funding from the National Institutes of Health to study whether Calypso's system can enable patients to receives higher doses of radiation, and fewer of them.

If that proves true, it would make a big difference in an inefficient field. Partly because of the inaccuracy of standard radiation, patients are now required to come to the clinic every day for eight weeks — 40 visits — to get low doses of radiation. It creates bottlenecks at the clinics, and is inconvenient for patients, Parikh said.

The Calypso system isn't much faster — Parikh said it may shave two to three minutes off each procedure. But that could mean a clinic could treat two extra patients per day, "which could be the difference between breaking even and making money," Parikh said. He also said the device is easy enough to use that it won't require much training — his technician learned to use it in five minutes, he said.

Parikh said skeptics in the field of radiation oncology question Calypso's studies, such as one published in the journal Medical Physics that reported two of 11 patients had prostates that moved more than one centimeter during an eight-minute period on the radiation table. Meier said a later trial confirmed that earlier finding.

Meier said Calypso plans to raise additional funding in the next 12 months to bankroll its product launch. The company, originally incubated by Frazier Healthcare Ventures in Seattle, already has raised venture capital from a long list of backers from around the world.

Luke Timmerman: 206-515-5644 or ltimmerman@seattletimes.com