Dr. Powell on the Risk of ILD with Trastuzumab Deruxtecan in HER2+ Breast Cancer

Charles Powell, MD, MBA, director of the Mount Sinai-National Jewish Health Respiratory Institute, discusses the risk of interstitial lung disease (ILD) in patients with HER2-positive metastatic breast cancer treated with trastuzumab deruxtecan (Enhertu).

An analysis that examined patients from the phase 1 J101 (NCT02564900) and A104 (NCT03383692) trials, as well as the phase 2 DESTINY-Breast01 trial (NCT03248492), showed that a majority of cases of ILD in this patient population occurred within the first 12 months of therapy, Powell says. Moreover, the incidence of ILD occurring after the first year of treatment is much smaller, which suggests that the toxicity is not cumulative. This will be important in terms of guiding the monitoring of patients who are on this therapy in the future, Powell explains.

Additionally, a majority of the ILD events reported were grades 1 or 2 in severity, Powell notes. This supports the idea that, if identified promptly, and treated appropriately—by withdrawal of the therapy as a well as treatment with steroids when clinically indicated—this toxicity is manageable, Powell concludes.