POSSIBLE SIDE EFFECTS

Possible side effects with DATROWAY

Certain side effects, including serious or even possibly fatal ones, were seen in people treated with DATROWAY. Make sure to tell your care team right away if you experience any side effects.

DATROWAY can cause serious side effects

  • Lungs icon

    Lung problems

    Lung problems that may be severe, life-threatening, or that may lead to death can occur with DATROWAY. If you develop lung problems, your doctor may treat you with corticosteroid medicines. Tell your care team right away if you have any of the following: cough, trouble breathing or shortness of breath, fever, or other new or worsening breathing symptoms such as chest tightness or wheezing.

  • Eye irritation icon

    Eye problems

    Eye problems are common with DATROWAY and can also be severe. Tell your care team right away if you develop any new or worsening eye problems during treatment with DATROWAY, including dry eyes, eye pain, eye redness, eye swelling, eye irritation, increased tears, feeling like something is in your eyes, discharge from your eyes, eye crusting, sensitivity to light, blurred vision, or vision changes.

  • Mouth sores icon

    Mouth ulcers and sores

    Mouth ulcers and sores are common with DATROWAY and can also be severe. Tell your care team right away if you develop mouth pain, swelling, redness, ulcers, or sores during treatment with DATROWAY.

  • Pregnancy icon

    Harm to your unborn baby

    DATROWAY may cause harm to your unborn baby. Tell your care team right away if you become pregnant or think you might be pregnant during treatment with DATROWAY.

    • If you are able to become pregnant, your care team should do a pregnancy test before you start treatment  
    • Females who are able to become pregnant should use effective birth control (contraception) during treatment and for 7 months after the last dose
    • Males who have partners who are able to become pregnant should use effective birth control (contraception) during treatment and for 4 months after the last dose

This is not a complete list of symptoms for DATROWAY-associated side effects or all possible side effects of DATROWAY. Call your doctor for medical advice about symptoms or side effects. You may report side effects to Daiichi Sankyo at 1-877-437-7763 or to FDA at 1-800-FDA-1088.

This is not a complete list of symptoms for DATROWAY-associated side effects or all possible side effects of DATROWAY. Call your doctor for medical advice about symptoms or side effects. You may report side effects to Daiichi Sankyo at 1-877-437-7763 or to FDA at 1-800-FDA-1088.

Common side effects seen with DATROWAY

The most common side effects of DATROWAY when used in adults with HR+/HER2– breast cancer include mouth ulcers and sores, nausea, tiredness, decreased white blood cell counts, decreased blood levels of calcium, hair loss, decreased red blood cell counts, constipation, dry eye, vomiting, increased blood levels of liver enzymes, inflammation of the cornea, and increased blood levels of alkaline phosphatase. 

In the trial, the majority of common side effects seen with DATROWAY were mild or moderate in severity. Mild side effects may not affect your daily activities, and medical intervention may not be needed. Moderate side effects may affect your daily activities and may require some medical intervention. Severe side effects usually require medical intervention and may have serious or life-threatening consequences.

Your doctor may reduce your dose of DATROWAY, interrupt treatment, or completely stop treatment if you have certain side effects.

Shield icon

Planning ahead

With any treatment, side effects are possible, so it’s important to plan ahead and decide with your care team the best course of action that may help prevent or treat certain side effects. After learning about the side effects seen in the clinical trials, review the Managing Side Effects page so that you and your care team can prepare ahead of time for possible side effects.

Battling cancer requires courage, resilience, and the right information to help keep you moving forward.

A woman stands in front of a blue and teal background with bokeh lights.
A woman stands in front of a blue and teal background with bokeh lights.
Not an actual patient.

Frequently asked questions

Open all
  • Q: How many people had to stop treatment because of side effects? 

    3.1% of people with unresectable or metastatic HR+/HER2– breast cancer receiving DATROWAY discontinued treatment due to side effects. Refer to the Managing Side Effects page for more information.

  • Q: Is there anything I can do that may help me with certain side effects?

    Consult your care team and refer to the Managing Side Effects page for more information on how you can help treat or possibly prevent certain side effects.

  • Q: How many people had serious side effects while on DATROWAY?

    Serious side effects occurred in 15% of the people with unresectable or metastatic HR+/HER2– breast cancer treated with DATROWAY.

Shield icon

Learn how to manage select side effects