Novocure is a global oncology company that has established a different approach to cancer therapy. Instead of relying on drugs, the company has pioneered a device-based treatment that uses a physical force to combat tumors, applying physics to target cancerous growths.
Understanding Tumor Treating Fields
Tumor Treating Fields (TTFields) are low-intensity, alternating electric fields that are delivered non-invasively to the part of the body where a tumor is located. The core mechanism of this technology targets the process of mitosis, or cell division. Cancer cells are characterized by their rapid and uncontrolled division, and TTFields are designed to interfere with this process, leaving healthy, non-dividing cells largely unaffected.
The electric fields exert physical forces on highly charged proteins within cancer cells that are essential for division. During mitosis, a structure called the mitotic spindle forms to pull duplicated chromosomes apart into two new daughter cells. This spindle is built from microtubules, which are polymers of a protein called tubulin. The electric fields disrupt the proper alignment and assembly of these tubulin proteins, preventing the mitotic spindle from forming correctly.
This interference leads to a cascade of problems for the dividing cancer cell. The chromosomes may not segregate properly, and the cell may be unable to complete the division process correctly. This abnormal mitosis can trigger a process called apoptosis, or programmed cell death. The shape of the dividing cell also makes it susceptible, as the electric field intensity increases at the narrow “neck” between the two emerging daughter cells, further disrupting the separation.
Approved Medical Uses
The application of TTFields therapy, delivered by a device branded as Optune, has received approval from regulatory bodies for treating specific types of aggressive cancers. One of the primary approvals is for the treatment of glioblastoma (GBM), the most common and aggressive form of brain cancer in adults. The Food and Drug Administration (FDA) has approved Optune for both newly diagnosed and recurrent cases of GBM.
For patients with newly diagnosed glioblastoma, Optune is used in conjunction with the standard-of-care chemotherapy, temozolomide, following initial treatment with surgery and radiation. Clinical trials showed that adding TTFields to chemotherapy improved both progression-free survival and overall survival compared to chemotherapy alone. In cases of recurrent GBM, the device is approved as a monotherapy.
Beyond brain tumors, the technology is also approved for treating malignant pleural mesothelioma, a rare and aggressive cancer affecting the lining of the lungs, often linked to asbestos exposure. For this cancer, the device, branded as Optune Lua, is used in combination with standard chemotherapy drugs.
The Patient Treatment Process
The system, known as Optune, consists of two main components: a set of transducer arrays that are applied directly to the skin and a portable field generator that powers them. The generator is carried by the patient in a specially designed bag, allowing for continuous treatment while maintaining mobility for daily activities.
The practical application requires a significant commitment from the patient. For glioblastoma treatment, the patient’s scalp must be kept shaved to ensure the transducer arrays maintain good contact with the skin. These arrays, which deliver the electric fields, are changed every few days by the patient or a caregiver, who receives training from a device support specialist. To be effective, the device must be worn for at least 18 hours a day.
The most common side effect is mild-to-moderate skin irritation at the site where the arrays are placed. This is generally manageable through proper skin care and by rotating the placement of the arrays slightly with each change. Unlike chemotherapy, the therapy does not cause systemic side effects because its action is localized to the tumor area.
Ongoing Research and Clinical Trials
Novocure is actively investigating the potential of Tumor Treating Fields to treat a wider range of solid tumors beyond its current approvals. The company has a broad clinical trial pipeline, with several late-stage, Phase 3 studies exploring the therapy’s effectiveness in other aggressive cancers.
Key areas of investigation include some of the most challenging cancers to treat. Late-stage trials are evaluating TTFields for non-small cell lung cancer (NSCLC), pancreatic cancer, and ovarian cancer. These studies are designed to determine if applying the electric fields to different parts of the body can provide a survival benefit for patients, often in combination with standard cancer therapies like chemotherapy or immunotherapy.
By testing its application against various tumor types, the company aims to expand its use and offer a new therapeutic option for patients with limited choices. Completed and ongoing trials in brain metastases and gastric cancer further underscore the breadth of this research program.