Yesterday the Israel-based oncology company NovoCure announced that its wearable, noninvasive therapy had achieved the longest median survival rate yet for these recurrent brain cancers. NovoCure's NovoTTF-100A is a sort of anticancer hat that patients can wear outside of the hospital. It continuously fires low-intensity electric fields into the brain while patients go about their daily lives. The electricity stunts cell growth and halts the tumor's uncontrolled progression, sparing healthy brain cells that rarely need to grow and divide.
"NovoTTF increases survival rates twofold, without the adverse effects of chemotherapy," says Eilon Kirson, Chief Medical Officer at NovoCure. "Patients reported better quality of life, and better cognitive and emotional functioning."
Obstacles to Wearable Devices
NovoTTF has been available since 2011, when the FDA approved the treatment for adult patients with recurrent glioblastoma. Although randomized clinical trials were conducted, the FDA approval was met with some resistance due to possible statistical anomalies. Later an independent study foundthat although NovoTTF patients reported less serious side effects, the wearable treatment simply did not improve survival rates when compared with conventional chemotherapy.
Despite these initial misgivings, insurers began covering NovoTTF—the cost of which is on par with chemotherapy—and 128 cancer centers in the U.S. have adopted the treatment since 2011. The most recent study, conducted by NovoCure, capitalized on the now-extensive database of 457 patients to analyze survival rates across a larger sample size. The study found that median survival rates doubled to about nine and a half months.
While subjects who receive conventional chemotherapy often suffer from anemia—low blood count, fatigue—and severe nausea, the NovoCure study reports that patients complained of virtually no device-related side effects, except for an occasional skin rash from the electrodes.
"It's very well-tolerated, and it usually doesn't interfere with quality of life," says Isabelle Germano, a professor of neurosurgery at Mount Sinai School of Medicine, who was not involved in the study. "I have patients who played golf while wearing it."
Fighting Cancer With Electricity
NovoTTF blasts tumors with alternating electric currents that stymie cell growth. By definition, cancer cells propagate uncontrollably, so most cancer treatments are aimed at halting the deadly progression.
But until recently cancer patients' options were relatively limited. "Existing [methods] for treating cancer are basically surgery, radiation, and chemotherapy," Kirson says. "We see electric fields as the next force in cancer treatment."
Most chemotherapy and radiation treatments destroy abnormal cells—along with nearby healthy cells—by damaging their DNA. Electric therapies, instead, target tumors by disrupting the highly sensitive, electrically driven process of cell division. In the brain this keeps collateral damage to a minimum, because healthy, adult brain cells rarely divide.
"The punch line is that, because this is a more mechanical distortion of the cell, the side effects are minimal as opposed to damaging the actual DNA," Germano says.
In the near future physicians may use wearable, alternating electric currents to treat a broader spectrum of cancers. "There have been preclinical, animal studies for melanoma, lung cancer, pancreatic cancer, and breast cancer," Germano says. "At least in the lab, the results look promising."
Making It Wearable
Cancer-killing electric currents are exciting, but perhaps the most important aspect of NovoTTF is that it's wearable. A lightweight, wearable therapy means that patients spend less time at treatment centers receiving chemotherapy and more time at home with their loved ones. "It's the future of treating cancer," Kirson says. "You don't have to do it alone anymore."
And while the NovoTTF is a fairly noticeable treatment worn on patients' heads, further research into breast cancer applications, for instance, could herald a subtler device. "Eventually, it could be worn on the chest or abdomen, under the clothes," says Kirson.
Patients currently carry the battery that powers NovoTTF in a satchel, or plug the system into a wall outlet when they are relaxing at home. In the coming months NovoCure will continue to work on designing an even more convenient wearable therapy.
"We're already working on the next generation, which will be smaller and even easier to carry around," Kirson says. "As electronics and batteries improve, this will slowly become a truly no-big-deal type of therapy."