Table 3.

Most Common Drug-Related Adverse Events (in ≥20% of Patients) in the Safety Analysis Set.^*

Event	Trastuzumab Deruxtecan (N = 371)		Physician’s Choice of Chemotherapy (N = 172)
	All Grades	Grade ≥3	All Grades	Grade ≥3
number of patients (%)
Blood and lymphatic system disorders
Neutropenia†	123 (33.2)	51 (13.7)	88 (51.2)	70 (40.7)
Anemia‡	123 (33.2)	30 (8.1)	39 (22.7)	8 (4.7)
Thrombocyopenia§	88 (23.7)	19 (5.1)	16 (9.3)	1 (0.6)
Leukopenia¶	86 (23.2)	24 (6.5)	54 (31.4)	33 (19.2)
Gastrointestinal disorders
Nausea	271 (73.0)	17 (4.6)	41 (23.8)	0
Vomiting	126 (34.0)	5 (1.3)	17 (9.9)	0
Diarrhea	83 (22.4)	4 (1.1)	31 (18.0)	3 (1.7)
Constipation	79 (21.3)	0	22 (12.8)	0
Investigations: increased amino transaminases ‖	87 (23.5)	12 (3.2)	39 (22.7)	14 (8.1)
General disorders: fatigue **	177 (47.7)	28 (7.5)	73 (42.4)	8 (4.7)
Metabolism and nutrition disorders: decreased appetite	106 (28.6)	9 (2.4)	28 (16.3)	2 (1.2)
Skin and subcutaneous tissue disorders: alopecia	140 (37.7)	0	56 (32.6)	0

^*Shown are adverse events that emerged or worsened after initiation of a trail drug until 47 days after the last dose of the trial drug and that were adjudicated as being related to a trial drug by an independent committee.

^†This category includes the preferred terms neutrophil count decreased and neutropenia.

^‡This category includes the preferred terms hemoglobin decreased, red-cell count decreased, anemia, and hematocrit decreased.

^§This category includes the preferred terms platelet count decreased and thrombocytopenia.

^¶This category includes the preferred terms white-cell count decreased and leukopenia.

^‖This category includes the preferred terms aminotransaminases increased, aspartate aminotransferase increased, alanine aminotransferase increased, γ-glutamyltransferase increased, liver function test abnormal, and hepatic function abnormal.

^**This category includes the preferred terms fatigue, asthenia, and malaise.