The STELLAR trial (also known as the “EF-23 trial”) is a Pilot (analogous to drug Phase II), single arm trial. It is designed to test the efficacy and safety of a medical device, the NovoTTF-100L system in patients with malignant pleural mesothelioma, when the device is combined with chemotherapy for mesothelioma. The device administers TTFields to patients concomitantly to the best standard of care treatments which would normally be used to treat their mesothelioma – pemetrexed and cisplatin or carboplatin. The trial is expected to enroll a total of 80 patients. The trial is now enrolling patients in multiple centers in Europe.

The STELLAR Trial Design

Patients with newly diagnosed, unresectable, and previously untreated malignant pleural mesothelioma are candidates for the clinical trial. Final eligibility can only be determined by the clinical trial physician at one of the clinical trial sites. All patients enrolled in the trial will receive the best standard treatments (including chemotherapy) for their mesothelioma and for any other medical condition, similar to patients who are not participating in the trial. All patients will receive TTFields combined the best standard of care chemotherapy for mesothelioma – pemetrexed and cisplatin or carboplatin. TTFields will be administered continuously to all patients enrolled in the trial, until disease progression. Eligible patients will start both chemotherapy and TTFields at the same time, and should therefore consult with their treating doctor about their potential participation in the trial soon after being diagnosed with mesothelioma.

In order to apply the NovoTTF-100L device, the patient needs to wear four transducer arrays taped on the upper torso. Routine transducer array placement (every 3-4 days) will require shaving of hair-containing skin surfaces with a simple shaver provided at treatment start, if relevant. Since the transducer arrays are placed on skin and covered by clothes, they may not be visible to others.

The use of the device will start in an outpatient setting and will include training on the operation of the equipment by a qualified Novocure Device Support Specialist (DSS). Patients will continue to use the device at home. Patients using the NovoTTF-100L System can maintain the use of the device alone (with the help of a family member or a care giver if needed) or receive support from their DSS.

The system is user-friendly and all technical aspects related to using it are maintained by the DSS. The DSS can also help patients in finding technical solutions to allow each individual to receive TTFields while maintaining his/her normal daily routines.


For the complete list of eligibility criteria please go to or consult with a STELLAR trial physician:

Inclusion Criteria (Summary, not complete list)

  1.  At least 18 years of age
  2. Diagnosis of unresectable malignant pleural mesothelioma
  3. No curative treatment by surgery or radiotherapy is planned

Exclusion Criteria (Summary, not complete list)

  1. Previous treatment with chemotherapy or radiotherapy
  2. Pregnant women
  3. Pacemaker or other implanted electronic devices


Expected total enrollment is 80 patients. The trial is currently enrolling in several European medical centers.  Please contact one of them as soon as possible if you would like to participate in the STELLAR trial.

Trial Costs

The trial sponsor (Novocure) will pay for reasonable treatment related supplies associated with trial procedures that are outside of the standard of care, including the NovoTTF-100L system and accessories. The trial sponsor will also reimburse patients for some travel costs related to trials procedure. Such reimbursement can be done only according to the policy of the trial center the patient is treated at and upon approval by the trial sponsor. Please consult with the clinical trial team at the center prior to enrolling in the trial about the local reimbursement policy and your rights. Patients and their insurance will be responsible for medical treatments received in the normal course of patient care.