DESTINY-Breast03 Phase 3 Study Results
Overall Safety Profile of HER3-DXd
Daiichi-Sankyo
• HER3-DXd was associated with a
•
•
manageable safety profile
There was a low rate of TEAEs associated
with treatment discontinuation (9.9%)
•
18 patients had TEAEs associated with treatment
discontinuation across all doses: pneumonitis (n=6),
disease progression (n=2), ejection fraction decreased
(n=2), ILD, malaise, peripheral edema, hepatotoxicity,
gastric cancer, mental status changes, extradural
hematoma, and general physical health deterioration (all
n=1)
6.6% of patients had treatment-related ILD
eventsa
Patients, n (%)
Median treatment duration:
5.9 mo (range 0.7-30.6 mo)
Any TEAE
Associated with death
4.8 mg/kg
n=48
6.4 mg/kg
n=98
47 (97.9)
98 (100)
All Doses
N=182
181 (99.5)
Associated with discontinuation
Associated with dose reduction
Associated with drug interruption
5 (10.4)
8 (8.2)
18 (9.9)
6 (12.5)
22 (22.4)
35 (19.2)
23 (47.9)
57 (58.2)
100 (54.9)
Associated with death
1 (2.1)b
6 (6.1)b
7 (3.8)b
Grade ≥3 TEAE
31 (64.6)
80 (81.6)
130 (71.4)
Treatment-related TEAE
47 (97.9)
97 (99.0)
180 (98.9)
0
1 (1.0)
1 (0.5)c
Grade ≥3
27 (56.3)
76 (77.6)
120 (65.9)
Serious TEAE
7 (14.6)
23 (23.5)
38 (20.9)
Adjudicated treatment-related ILDd
Grade 1
0
2 (2.0)
3 (1.6)
Grade 2
1 (2.1)
2 (2.0)
5 (2.7)
Grade 3
0
2 (2.0)
3 (1.6)
•
Most were grade 1 and 2 (4.4%)
•
There was one grade 5 ILD event (0.5%)
Grade 4
0
0
0
Grade 5
Total
0
1 (1.0)
1 (0.5)
1 (2.1)
7 (7.1)
12 (6.6)
ILD, interstitial lung disease; TEAE, treatment-emergent adverse event.
a As determined by an independent adjudication committee. b TEAEs associated with death included disease progression (n=4), neutropenic sepsis (n=1), extradural hematoma (n=1), and choking (n=1). Treatment-
related TEAE associated with death was neutropenic sepsis (n=1). d Median time to onset, 141.5 days (95% CI; 36-584 days).
ASCO 2022 #1002 Oral
92
22View entire presentation