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SIDE EFFECTS

Actor portrayals.

Skin irritation is the most common device-related side effect

Skin irritation may look like a red rash, small sores, or blisters on your chest or back. Identifying it early and contacting your doctor will help ensure you don’t miss any time on treatment. Be sure to ask for your care partner’s help for any hard-to-see places.

In the clinical study

76.3% of people experienced skin irritation, which was mostly mild to moderate.

8.4% of patients had to stop using Optune Pax® because of side effects related to using the device.

In the study, the most common side effect caused by Optune Pax was skin irritation. Other side effects were attributed to cancer drugs or the cancer itself.* Optune Pax didn’t worsen chemotherapy-related side effects.

Additional side effects

When looking at all serious medical problems reported in the clinical study of Optune Pax, the table below shows how often serious medical problems occurred in the group of patients using Optune Pax with cancer drugs and the group of patients using only cancer drugs. The medical problems and how often those medical problems occurred in the group treated with Optune Pax and cancer drugs was similar to the group treated with only cancer drugs.*

*Cancer drugs=gemcitabine and nab-paclitaxel.

Other side effects may occur. See the Patient Information and Operations Manual (PIOM) for more information about side effects.

Caring for your skin is important when using Optune Pax

Learn best care tips

Indication and Important Safety Information

What is Optune Pax® approved to treat?

Optune Pax is an FDA-approved, wearable therapeutic device, used together with gemcitabine and nab-paclitaxel (a chemotherapy combination). It is indicated for the treatment of adult patients with locally advanced pancreatic cancer.

Who should not use Optune Pax?

Optune Pax for locally advanced pancreatic cancer is not for everyone. Talk to your doctor if you have:

  • An electrical implant. Use of Optune Pax together with electrical implants has not been tested and may cause the implanted device not to work properly
  • A known sensitivity to gels like the gel used on electrocardiogram (ECG) stickers or transcutaneous electrical nerve stimulation (TENS) electrodes. In this case, skin contact with the gel used with Optune Pax may commonly cause increased redness and itching. In rare cases, it may lead to severe allergic reactions that can cause a drop in blood pressure and difficulty breathing

Do not use Optune Pax if you are pregnant or are planning to become pregnant. If you are a woman who is able to get pregnant, you must use birth control when using the device. It is not known if Optune Pax is safe or effective during pregnancy.

What should I know before using Optune Pax?

Optune Pax should only be used after receiving training from qualified personnel, such as your doctor, a nurse, or other medical staff who have completed a training course given by Novocure®, the maker of Optune Pax.

  • Do not use any parts that did not come with the Optune Pax Treatment Kit sent to you by Novocure or given to you by your doctor
  • Do not get the device or transducer arrays wet
  • Please be aware that Optune Pax has a cord that plugs into an electrical socket. Be careful of tripping when it's connected
  • If you have an underlying skin condition where the transducer arrays are placed, discuss with your doctor whether this may prevent or temporarily interfere with Optune Pax treatment

What are the possible side effects of Optune Pax?

The most common side effects of Optune Pax used together with chemotherapy drugs were low neutrophils, low red blood cell count, low platelet count, low white blood cell count, diarrhea, nausea, vomiting, abdominal pain, constipation, fatigue, swelling, fever, pain, COVID-19, infection, respiratory tract infection, urinary tract infection, pneumonia, liver enzyme increased, weight loss, low potassium level, low albumin level, high blood sugar, muscle pain, neuropathy peripheral (damage to the nerves outside the brain and spinal cord), taste disorder, dizziness, difficulty sleeping, shortness of breath, hair loss, skin-related disorders, and low blood pressure.

Device-related skin adverse effects associated with the use of Optune Pax include skin inflammation, rash, itching, flat or raised spots, skin redness, skin irritation, skin reaction, and open sores. Other device-related adverse effects associated with the use of Optune Pax include overheating of the array, leading to pain and/or local skin burns, allergic reaction to the adhesive or gel from the transducer arrays, and local warmth and tingling sensation beneath the arrays. Talk to your doctor if you have any of these side effects or have any questions.

Please see the full Patient Information and Operation Manual (PIOM) for Optune Pax at OptunePax.com.

 

Indication and Important Safety Information

What is Optune Pax® approved to treat?

Optune Pax is an FDA-approved, wearable therapeutic device, used together with gemcitabine and nab-paclitaxel (a chemotherapy combination). It is indicated for the treatment of adult patients with locally advanced pancreatic cancer.

Who should not use Optune Pax?

Optune Pax for locally advanced pancreatic cancer is not for everyone. Talk to your doctor if you have:

  • An electrical implant. Use of Optune Pax together with electrical implants has not been tested and may cause the implanted device not to work properly
  • A known sensitivity to gels like the gel used on electrocardiogram (ECG) stickers or transcutaneous electrical nerve stimulation (TENS) electrodes. In this case, skin contact with the gel used with Optune Pax may commonly cause increased redness and itching. In rare cases, it may lead to severe allergic reactions that can cause a drop in blood pressure and difficulty breathing

Do not use Optune Pax if you are pregnant or are planning to become pregnant. If you are a woman who is able to get pregnant, you must use birth control when using the device. It is not known if Optune Pax is safe or effective during pregnancy.

What should I know before using Optune Pax?

Optune Pax should only be used after receiving training from qualified personnel, such as your doctor, a nurse, or other medical staff who have completed a training course given by Novocure®, the maker of Optune Pax.

  • Do not use any parts that did not come with the Optune Pax Treatment Kit sent to you by Novocure or given to you by your doctor
  • Do not get the device or transducer arrays wet
  • Please be aware that Optune Pax has a cord that plugs into an electrical socket. Be careful of tripping when it's connected
  • If you have an underlying skin condition where the transducer arrays are placed, discuss with your doctor whether this may prevent or temporarily interfere with Optune Pax treatment

What are the possible side effects of Optune Pax?

The most common side effects of Optune Pax used together with chemotherapy drugs were low neutrophils, low red blood cell count, low platelet count, low white blood cell count, diarrhea, nausea, vomiting, abdominal pain, constipation, fatigue, swelling, fever, pain, COVID-19, infection, respiratory tract infection, urinary tract infection, pneumonia, liver enzyme increased, weight loss, low potassium level, low albumin level, high blood sugar, muscle pain, neuropathy peripheral (damage to the nerves outside the brain and spinal cord), taste disorder, dizziness, difficulty sleeping, shortness of breath, hair loss, skin-related disorders, and low blood pressure.

Device-related skin adverse effects associated with the use of Optune Pax include skin inflammation, rash, itching, flat or raised spots, skin redness, skin irritation, skin reaction, and open sores. Other device-related adverse effects associated with the use of Optune Pax include overheating of the array, leading to pain and/or local skin burns, allergic reaction to the adhesive or gel from the transducer arrays, and local warmth and tingling sensation beneath the arrays. Talk to your doctor if you have any of these side effects or have any questions.

Please see the full Patient Information and Operation Manual (PIOM) for Optune Pax at OptunePax.com.

 

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US-OPP-00008 v1.0 April 2026