Monitoring Delayed Immune-Related Adverse Events With Adjuvant Durvalumab

In an interview with CancerNetwork®, Sunnie Kim, MD, associate professor of medicine in the Division of Medical Oncology at the University of Colorado School of Medicine, and a gastrointestinal medical oncologist at the University of Colorado Cancer Center, discussed her approach to monitoring and managing long-term immune-related adverse events in patients with gastroesophageal cancer receiving extended adjuvant checkpoint inhibitor therapy, such as durvalumab (Imfinzi), after surgery.

Kim noted that monthly visits during adjuvant durvalumab allow for close monitoring. She described watching endocrine function, including thyroid-stimulating hormone and electrolytes for signs of adrenal insufficiency, along with kidney function, vital signs, and imaging for rarer toxicities such as nephritis and pneumonitis. She emphasized that subtle toxicities require clinicians to ask the right questions and follow laboratory values closely.

Transcript:

Kim: As we all know, there are a lot of delayed immune-related adverse events that happen with PD-1 and PD-L1 inhibitors. Fortunately, for these patients who are getting durvalumab on the back end after surgery, we’re seeing them monthly. For the most part, we’re able to monitor these patients pretty closely and see if any emerging immune-related toxicities are occurring. Of course, that means watching their endocrine function, looking at [thyroid-stimulating hormone], and looking for any signs of adrenal insufficiency, too. Sometimes you can see that in the electrolytes, and if patients are feeling more fatigued, have malaise, or feel like they’re coming down with the flu, my antenna for endocrine dysfunction goes way up.

Other things include watching their kidney function, making sure that they’re not developing the rarer toxicities like immune-related nephritis, and checking their vitals very closely. If they start having an oxygen desaturation, or if we’re seeing signs of pneumonitis on scans, we need to be aware of how to pause the drug and reinstate it safely. Of course, there are the more common adverse effects like rash and diarrhea. Those are a little bit more obvious, and those are symptoms that patients will sometimes report directly to us. For some of the more subtle toxicities, practitioners need to be aware, be asking patients the right questions, and make sure that we’re following the lab work closely.