ERBB2 and interstitial lung disease: However, rates of ILD/pneumonitis events observed in both cohorts (16% (grade 5: 2%) and 13% (grade 5: 1%) of patients with and without baseline BMs, respectively) were consistent with T-DXd data for patients with HER2+ mBC in the DESTINY-Breast01 (16%; grade 5: 3%), DESTINY-Breast02 (10%; grade 5: <1%) and DESTINY-Breast03 (15%; grade 5: 0) studies35–37.