- Immunotherapy has revolutionized the treatment of many different types of cancers.
- Immune checkpoint inhibitors (ICPi) targeting cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), programmed cell death-1 (PD-1), and PD ligand 1 (PD-L1) work by preventing the receptors and ligands from binding to each other, thereby disrupting signaling so that T-cells can recognize and attack cancer cells. They are currently the standard of care in the treatment of several cancers, including a variety of solid-organ and hematological malignancies.
- The use of ICPis is rising exponentially, with approximately 40% of patients with cancer in the United States in 2019 eligible for treatment with ICPis.
- Immune checkpoint blockade therapy is associated with a spectrum of side effects that is quite different from other systemic therapies such as cytotoxic chemotherapy.
- Moderate to severe immune-related adverse events (irAEs) may be associated with life-threatening declines in organ function and quality of life, and fatal outcomes have been reported.
The following are general recommendations that should be followed irrespective of affected organs. For organ-specific and systemic toxicities management, please see Tables 1–11.
It is recommended that clinicians manage toxicities as follows:
- Patient and family caregivers should receive timely and up-to-date education about immunotherapies, their mechanism of action, and the clinical profile of possible irAEs before initiating therapy and throughout treatment and survivorship.
- There should be a high level of suspicion that new symptoms are treatment-related.
- In general, ICPi therapy should be continued with close monitoring for Grade 1 toxicities, except for some neurologic, hematologic, and cardiac toxicities.
- Consider holding ICPis for most Grade 2 toxicities and resume when symptoms and/or lab values revert ≤ Grade 1. Corticosteroids (initial dose of 0.5–1 mg/kg/day of prednisone or equivalent) may be administered.
- Hold ICPis for Grade 3 toxicities and initiate high dose corticosteroids (prednisone 1–2 mg/kg/day or equivalent). Corticosteroids should be tapered over the course of at least 4–6 weeks. If symptoms do not improve with 48–72 hours of high dose steroid, infliximab may be offered for some toxicities.
- When symptoms and/or lab values revert ≤ Grade 1, rechallenging with ICPis may be offered, however, caution is advised especially in those patients with early-onset irAEs. Dose adjustments are not recommended. Rechallenge with PD-1/PD-L1 monotherapy may be offered in patients with toxicity from combined therapy with a CTLA-4 antagonist once recovered to ≤ Grade 1.
- In general, Grade 4 toxicities warrant permanent discontinuation of ICPis, except for endocrinopathies that have been controlled by hormone replacement.
All recommendations in this guideline are consensus based with benefits outweighing harms.