Be Aware of Toxicities From Immune Checkpoint Inhibitors

You’ll get questions about adverse effects with immune checkpoint inhibitors (ICIs) as use increases.

Immune checkpoint inhibitors, such as pembrolizumab (Keytruda) or nivolumab (Opdivo), are a common type of cancer immunotherapy.

Cancer immunotherapy works by helping the patient’s immune system find and kill cancer cells. It’s different from chemotherapy, which directly targets dividing cells...malignant or healthy.

Be aware that toxicities can occur at any time, even months or more after stopping an ICI...and can be life-threatening.

Listen for patients reporting immune-related adverse effects...due to a revved up immune system. These can impact any body system.

The most common are dermatologic (rash, pruritis, etc)...or GI (diarrhea, colitis, etc) effects. Other common toxicities include endocrine disorders, hepatitis, and pneumonitis.

Refer patients with these symptoms to their prescriber to pinpoint med toxicity versus other culprits, such as C. diff in a patient with colitis...or a viral infection causing elevated liver enzymes.

Expect to see prednisone or methylprednisolone used to treat the majority of severe ICI toxicities...and many moderate cases.

Temporary steroid-induced immunosuppression doesn’t seem to diminish antitumor effects.

Once symptoms are minimal, steroids are generally tapered over at least 4 to 6 weeks.

If there’s no response to steroids in 2 to 3 days, expect patients to get additional immunosuppressants (infliximab, mycophenolate, etc).

Suggest adjuncts as needed, such as loperamide and hydration for colitis...an antihistamine for rashes...or a beta-blocker for thyrotoxicosis.

Remind patients to carry a wallet card that lists their immunotherapy...or keep the information in their phone.

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