Pneumonitis is emerging as an adverse event of many oncology targeted therapies, including immune checkpoint inhibitors and some tyrosine kinase inhibitors. On September 13, the US Food and Drug Administration (FDA) released an important safety communication regarding the risk of lung inflammation, including pneumonitis and interstitial lung disease, associated with another class of targeted therapies: the CDK4/6 inhibitors used in patients with breast cancer. All 3 currently approved CDK4/6 inhibitors—palbociclib, ribociclib, and abemaciclib—will now carry warnings in their prescribing information regarding the potential for lung inflammation and the need to provide education to patients regarding early symptoms of these infections. As with the other targeted therapies in oncology, the FDA indicated that the benefit of treatment with CDK4/6 inhibitors still outweighs the potential risk of pneumonitis.
High Altitude: Pneumonitis is a treatment-associated adverse event that, while historically rare, is becoming more common with the emergence of novel targeted therapies. In addition to CDK4/6 inhibitors, many currently approved PD-1 and PD-L1 inhibitors are associated with pneumonitis. The rise in rates of pneumonitis highlight a need for education for the entire treatment team to identify potential risk factors, appropriate steps for monitoring, early signs and symptoms, and if management of patients with pneumonitis can be further improved. Additionally, efforts to determine the underlying cause of treatment-associated pneumonitis could possibly allow for further strategies to mitigate the risk of pneumonitis in cancer patients.
Ground Level: One of the common hurdles that community oncologists face when incorporating new treatments into clinical practice is management of the adverse event profiles of novel therapies, especially inflammatory events. This caution for CDK4/6 inhibitors from the FDA provides an important update to prior warnings of pneumonitis with other targeted therapies for cancer. Together, these warnings highlight the need for proactive monitoring and education for cancer patients receiving targeted therapies, including CDK4/6 inhibitors, on the early signs and symptoms of pneumonitis to allow for early diagnosis and treatment.