TMC PULSE

t m c » p u l s e | m ay 2 0 1 9 16 Jon Schwartz, Ph.D., director of clinical research at Nanospectra Biosciences, holds a laser with an illuminated guide light, used in the clinical trial. "The problem with radical treat- ment for prostate cancer is remov- ing the whole prostate or radiating the whole prostate along with tes- tosterone suppression therapy has a lot of side effects," Canfield said. "It can lead to urinary problems including incontinence, sexual prob- lems and impotency—sometimes permanently. Radiation can lead to scarring and bladder and bowel problems, and hormone treatments can make people incredibly tired and have all sorts of other medical complications." In stark contrast, the patients in Canfield's clinical trial are treated with AuroLase therapy. In this two- part process, patients are infused intravenously with a black solution containing the gold nanoparticles (AuroShells) on the first day and sent home to allow the nanoparti- cles to disperse throughout the body and find the cancerous tumors. The next day, the patients return for laser therapy. "This is an outpatient proce- dure. You don't have to stay in the hospital; you could theoretically be feeling great the next day," Canfield said. "That is quite different from surgery. Even with minimally inva- sive surgery now, there is still going to be a recovery period. With radia- tion, you are looking at at least eight weeks of treatment, and the smallest time frame of hormone suppression you are going to get is six months. For high-risk disease, you are look- ing at two years or more, so it is an incredibly different quality-of-life treatment." When the patient comes back for the second phase of the AuroLase treatment, laser light is applied to the lesions where the nanoparticles have collected most heavily. Using MRI imaging and an ultrasound device, doctors seek and destroy cancerous areas. To target these areas, a trocar (normally used for laparoscopic procedures) is placed into the lesion and a catheter is inserted in the prostate gland, pre- cisely where treatment is desired. Once the targeted location is identi- fied, doctors remove the cancerous areas with a laser by heating up the nanoparticles to make the gold vibrate and destroy the disease. The nanoparticles are designed to absorb light in the area of the electromagnetic spectrum called the "near infrared," the region clos- est in wavelength to radiation that is perceptible to the human eye. "The nanoparticles, when you shine light on them, will absorb light very efficiently," Halas said. "Then they convert the light to heat and they'll heat in their local vicinity so they have an extremely local- ized heat source—so they heat only where the particle is placed." $6.50 worth of gold Billingsley hardly missed a beat after his treatment. "I had it done on Wednesday, I was at a Christmas party on Saturday and back at work on Monday. It was a quick, easy recovery," he said. The worst-case scenario is that the gold nanoparticles undertreat the prostate cancer so there might be a sliver missed—most likely because the lasers didn't activate those areas, Canfield explained. That would be a miss and a treat- ment failure. But you don't miss the chance to do any of the traditional treatments you had been consider- ing in the first place, he added, and because prostate cancer is so slow growing, nothing is really likely to have changed and you probably removed the vast majority of the cancer even in a failure case. "At the end of the day, they only put about $6.50 worth of gold in me," Billingsley said. "It was exciting to be on the forefront of anything in Houston—we are that kind of town. We have the best med center in the country, if not the world. Our space program, our sports programs … I've watched them all grow up in 20 years. Television is always on the cutting edge of technology, so the business I'm in is always out there doing something pioneering. To take a chance on something that I thought made sense in a community that I trusted didn't bother me." The clinical trial is being con- ducted at UTHealth, Mt. Sinai and the University of Michigan. "Now, all three sites have patients enrolled," Canfield said. "This first phase of the trial has 45 clinical patients and we are up to 39 patients so we need six more and this trial will end. We have already started to plan for the second trial and that will be, in total, 55 patients. That will be enough for the FDA to start approv- ing us as an available treatment." Canfield and Halas hope the AuroLase therapy will be expanded to treat other cancers in the near future. "I think skin cancer would be an ideal candidate for this treatment. There are lots of ways you can sat- urate a skin cancer," Canfield said. "You can saturate it with nanoparti- cles and you can just activate those by shining a light just over the skin. You don't have to put it inside the body or anything. Kidney, liver, breast cancer—anything where you can see the area and then place a laser there will work well." This is an outpatient procedure. You don't have to stay in the hospital; you could theoret- ically be feeling great the next day. — STEVEN CANFIELD, M.D. Chief of urology at McGovern Medical School at UTHealth

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