Grade 1: N/A

Grade 2: resting EF 50 to 40%; 10 to 19% drop from baseline

Grade 3: resting EF 39 to 20%; ≥ 20% drop from baseline

Grade 4: resting EF < 20%

Reference: Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0 Published: November 27, 2017