The FDA issued a safety alert today indicating that three drugs used to treat some patients with advanced breast cancer may cause rare but severe lung inflammation.
All three therapies — palbociclib (Ibrance, Pfizer), ribociclib (Kisqali, Novartis) and abemaciclib (Verzenio, Eli Lilly) — are cyclin dependent kinase (CDK) 4/6 inhibitors.
The FDA approved adding warnings to the prescribing information and patient package insert for the entire class of CDK 4/6 inhibitors.
However, the agency’s safety alert emphasized “the overall benefit of CDK 4/6 inhibitors is still greater than the risks when used as prescribed.”
CDK 4/6 inhibitors are used in combination with hormone therapies to treat adults who have hormone receptor-positive, HER2-negative advanced or metastatic breast cancer.
The FDA approved palbociclib in 2015, and it approved ribociclib and abemaciclib in 2017.
The agency urged patients using these drugs to notify their health care providers immediately if they experience new or worsening symptoms involving their lungs. These symptoms may include discomfort or difficulty with breathing, as well as shortness of breath while at rest or during low activity.
The alert emphasizes patients should not stop taking these medications without consulting a health care professional.
Health care professionals should monitor patients for pulmonary symptoms that may indicate interstitial lung disease or pneumonitis. These symptoms include hypoxia, dyspnea, cough, and interstitial infiltrates on radiologic exams in cases when neoplastic, infectious or other causes have been excluded.
CDK 4/6 inhibitor therapy should be interrupted for patients who have new or worsening respiratory symptoms, according to the FDA. Treatment should be permanently discontinued for patients with severe interstitial lung disease and/or pneumonitis.
No risk factors have been identified to determine which patients may experience lung inflammation while using these therapies, according to the FDA alert.
Patients and clinicians are encouraged to report side effects or adverse events related to these therapies through the FDA’s MedWatch Safety Information and Adverse Event Reporting Program. A reporting form may be accessed here. Forms also may be obtained by calling (800) 332-1088.