DESTINY-Breast03 Phase 3 Study Results
Poster 465
Retrospective study to estimate the prevalence
of HER2-low breast cancer (BC) and describe
its clinicopathological characteristics
Giuseppe Viale, MD, FRCPath'; Naoki Niikura, MD, PhD²; Eriko Tokunaga, MD3; Mark Basik, MD4;
Naoki Hayashi, MD5; Joohyuk Sohn, MD, PhD; Ciara O'Brien, PhD; Gavin Higgins, PhD;
Della Varghese, PhD; Gareth D. James 10; Akira Moh, MD, PhD11; Nana Scotto, MD12
'European Institute of Oncology IRCCS and University of Milan, Milan, Italy. "Tokai University School of Medicine, Kanagawa, Japan; *National Hospital Organization Kyushu Cancer
Center, Fukuoka, Japan; *Jewish General Hospital, McGill University, Montreal, QC, Canada: $St. Luke's International Hospital, Tokyo, Japan; "Yonsei Cancer Center, Yonsei University
College of Medicine, Seoul, Korea; 'The Christie NHS Foundation Trust, Manchester, UK; *Victoria Cancer Biobank, Melbourne, VIC, Australia; "AstraZeneca Pharmaceuticals LP,
Gaithersburg, MD; Medical Statistics Consultancy Ltd, London, UK; 11Daiichi Sankyo Inc., Basking Ridge, NJ; 12AstraZeneca Pharmaceuticals, Cambridge, UK
Objectives
⚫ The objectives were to (1) assess the prevalence of human epidermal growth factor receptor 2 (HER2)-low expression
(immunohistochemistry [IHC] 1+ or IHC 2+/in situ hybridization [ISH]-; ie, HER2-low BC) among patients with
unresectable/metastatic BC (mBC) originally scored as HER2 negative based on rescored HER2 IHC slides after training
on low-end expression scoring; (2) describe characteristics, clinical presentation, treatment patterns, and clinical
outcomes of patients with HER2-low vs HER2 IHC 0 mBC; and (3) characterize the concordance between HER2 IHC
rescores and historical scores
- Here we report interim analysis data with an expanded data set (392 of 800 planned patients) from that previously
reported in the abstract (233 patients)
Conclusions
⚫ In this study of mBC samples previously categorized as HER2-negative, the prevalence of HER2-low status was 61.2%
- HER2-low prevalence was numerically higher among patients with hormone receptor (HR)-positive mBC compared
with HR-negative mBC (66.4% and 46.0%, respectively)
Data on HER2-low prevalence in BC are limited, but this estimated prevalence is similar to that in a previous study of
HER2-negative BC samples (60%) 1
⚫ The overall concordance rate for HER2 status classification between historical and rescored slides was 79.1% ( [95%
CI], 0.554 [0.468-0.640]) indicating that historical scores were relatively accurate in identifying patients with HER2-low BC
- Overall concordance was similar in the Ventana 4B5 and non-Ventana 4B5 cohorts (79.5% and 78.7%, respectively)
⚫ HER2-low and HER2 IHC 0 groups had similar demographic and baseline disease characteristics
As HER2-targeted therapies such as trastuzumab deruxtecan (T-DXd) for the treatment of patients with HER2-low BC
are emerging, 2-6 a greater understanding of patients with HER2-low expression who could benefit from these therapies is
important
Introduction
⚫ HER2-negative BC (IHC 0, 1+, or IHC 2+/ISH-) comprises -80% of all BCS7; however, -60% of BCS traditionally categorized as HER2 negative express
low levels of HER2 (IHC 1+ or IHC 2+/ISH-)1
•⚫ HER2-targeted therapies for HER2-low mBC are under investigation (eg, T-DXd in the phase 3 DESTINY-Breast04 study [NCT03734029] and the
phase 2 DAISY trial [NCT04132960]). 2-5 In DESTINY-Breast04, T-DXd demonstrated superior progression-free survival in previously treated patients with
HER2-low mBC vs the standard of care; the safety profile of T-DXd was consistent with previous trials2
• As patients with HER2-low BC become a clinically relevant population and the HER2 paradigm shifts from binary categorization to more nuanced
recognition of the continuum of HER2 expression, accurate identification of patients with HER2-low BC is important
- HER2 assays currently used to select patients for approved anti-HER2 therapies are optimized for high HER2 expression and are not validated for
HER2-low detection. A recent study found relatively poor concordance (19% of cases had <70% interrater agreement) in evaluation of IHC scores of 0
and 1+ using current HER2 assays, which underscores the need to understand the performance of HER2 assays for detection of HER2-low BC⁹
⚫ Here we report the overall prevalence of HER2-low status among patients with unresectable/mBC identified as HER2 negative based on rescoring of
historical HER2 IHC slides. We also describe patient characteristics, treatment patterns, and outcomes in HER2-low and HER2 IHC 0 mBC and the
concordance between HER2 IHC rescores and historical scores
Results and interpretation
HER2-low prevalence within the HER2-negative population
• HER2 rescores were available for 384 of 392 patients
⚫ HER2-low prevalence was 61.2% overall and numerically greater in the HR-positive subgroup vs
HR-negative subgroup (66.4% vs 46.0%; Figure 1)
- No notable differences in prevalence were seen when rescores were assessed using the
Ventana 4B5 and other assays (P=.8524)
Figure 1. HER2-low prevalence in the HER2-negative mBC population
Assay
Breast
cancer
235/384
All (N=384) 188/283
46/100
61.2
66.4
46.0
Methods
Study design
This global, multicenter, retrospective study (NCT04807595)
included patients with confirmed HER2-negative (HER2 IHC 0,
1+, or 2+/ISH-) unresectable/mBC diagnosed from 2014
through 2017 (date of mBC diagnosis was the index date)
- Patients from Australia, Canada, France, Italy, Japan, Korea,
and United Kingdom were included
• Staff at local laboratories, blinded to historical HER2 scores,
rescored HER2 IHC-stained slides
- HER2 was assessed using Ventana 4B5 and other assays
(eg, HercepTestTM [DAKO] or Bond Oracle™ [Leica])
⚫ BCs were categorized as HER2-low (IHC 1+ or IHC 2+/ISH-) or
HER2 IHC 0
Patient demographics and clinicopathological characteristics
⚫ No notable differences in demographic or baseline disease characteristics between the HER2-low
and HER2 IHC 0 groups were seen (Tables 1 and 2)
At index date, most patients (291/392; 74.2%) were HR positive, most (75.3%) were ≥45 years of
age, and most (79.6%) were Asian or White
Visceral (58.9%) and bone (45.2%) metastases were commonly observed among reported
metastatic sites; most patients (55.4%) reported 1 metastatic site
Table 1. Patient demographics
12 (26.1)
13 (24.1)
Outcomes
• The prevalence of HER2-low BC among patients originally scored as HER2
negative was measured
⚫ Demographics, clinicopathological characteristics, treatment patterns, and
outcomes were examined via medical charts/electronic health records
- Data cutoff was December 31, 2020 (ie, >3 years of follow-up post index date)
• Concordance between historical HER2 scores and rescores was also assessed
using Cohen's kappa (k), with к describing the relative strength of agreement
using the following scale: 10
->0.8, almost perfect; 0.6-0.8, substantial; 0.4<x<0.6, moderate; 0.2<<0.4,
fair; Oss0.2, slight; <0, poor
• Time-to-event outcomes were estimated using Kaplan-Meier method and
reported as medians and 95% CI
Treatment patterns and outcomes
• Most patients (50.0 % -78.2%) received monotherapy as their first treatment in the metastatic setting;
21.8% -50.0% had combination therapy, of whom 15% received CDK4/6 inhibitors (Figure 3)
⚫ Median time to first subsequent treatment and overall survival (OS) were numerically greater for
HER2-low than for HER2 IHC 0 with 1 exception (OS in patients who were HR positive and did not
receive CDK4/6 inhibitors; Figures 4 and 5)
Patients, %
The magnitude of the differences in median OS between HER2-low and HER2 IHC 0 was generally
larger among HR-negative than HR-positive groups
Figure 3. First treatment received in the metastatic setting
50.0
47.2
50.0
47.2
HR+ HER2-low (n-150)
HR+ HER2 IHC 0 (n-78)
HR-HER2-low (n-36)
HR-HER2 IHC 0 (n-36)
HR positive
HR negative
Total
HER2-low
(N=188)
HER2 IHC 0 Total"
(N=95)
(N=291)
HER2-low
(N=46)
HER2 IHC 0 Total
(N=54)
(N=392)
(N=100)
100.0-
Female, n (%)
187 (99.5)
94 (98.9)
288 (99.0)
46 (100.0)
54 (100.0)
100 (100.0)
389 (99.2)
90.0
Median age at Index date, median
(range), years
60 (27-93)
56 (28-90)
59 (27-93)
57 (31-80)
51 (35-92)
53 (31-92)
57 (27-93)
78.2
80.0
Total
Age group at Index date, n (%)*
70.0
18 to 44 years
23 (12.2)
11 (11.6)
36 (12.4)
9 (19.6)
16 (29.6)
25 (25.0)
61 (15.6)
61.5
75/126
Primary (n=126) 66/104
59.5
63.5
HR positive
45 to 64 years
82 (43.6)
48 (50.5)
134 (46.0)
23 (50.0)
20 (37.0)
43 (43.0)
177 (45.2)
60.0-
52.8
52.7
≥65 years
66 (35.1)
27 (28.4)
93 (32.0)
25 (25.0)
50.0
118 (30.1)
9/22
40.9
HR negative
50.0
Not reported/missing
1 (0.5)
2 (0.7)
0
0
0
2(0.5)
40.0
157/255
61.6
Smoking status
"never." n (%)
110 (58.5)
61 (64.2)
178 (612)
30 (65.2)
34 (63.0)
64 (64.0)
242 (61.7)
Metastatic (n=255) 119/176
67.6
Race, n (%)
30.0
Aslan
82 (43.6)
38 (40.0)
125 (43.3)
14 (30.4)
23 (42.6)
37 (37.0)
163 (41.6)
37/78
47.4
20.0
White
67 (35.6)
34 (35.8)
101 (34.7)
23 (50.0)
25 (46.3)
48 (48.0)
149 (38.0)
Black or African American
1 (0.5)
1 (1.1)
2 (0.7)
1 (2.2)
0
1 (1.0)
3 (0.8)
10.0
6.0 5.1
Other
2(1.1)
0
2 (0.7)
0
0
2 (0.5)
0.0
36 (19.1)
22 (23.2)
60 (20.6)
8 (17.4)
5 (11.1)
14 (14.0)
75 (19.1)
Any
Endocrine therapy
Chemotherapy
Any
Monotherapy
Not reported/missing
*Includes patients with missing HER2 category.
Includes patients with missing HR status.
Index date was the date of mBC diagnosis
0
0
21.8
20.0
16.7
Aromatase inhibitors +
CDK4/6 inhibitors
Combination therapy
118/193
61.7
Ventana 4B5 (n=193) 101/149
67.8
18/44
40.9
Plain language summary
Why did we perform this research?
Breast cancers can have high levels of the HER2 protein (HER2-positive breast cancer), low levels of the
HER2 protein (HER2-low breast cancer), or no HER2 protein (HER2-negative breast cancer). About 60%
of breast cancers historically classified as HER2 negative are HER2-low breast cancers. Some anticancer
like trastuzumab deruxtecan (T-DXd), are designed to target and kill cancer cells that express
drugs,
HER2.2.3 T-DXd may be able to treat HER2-low breast cancer, but the tests to detect HER2 are not
sensitive for low amounts of HER2.47 We wanted to find out how many patients who were historically
categorized as having HER2-negative breast cancer should actually be considered as having HER2-low
breast cancer. We also wanted to describe the differences between characteristics of patients with breast
cancer that was identified as HER2-low and characteristics of patients with breast cancer that had no
HER2 expression detected (immunohistochemistry [IHC] score of 0).
How did we perform this research?
Patients who were diagnosed with HER2-negative unresectable or metastatic breast cancer from 2014
through 2017 were included. Staff at local laboratories, who did not know how the tissue biopsies were
scored when the patients were diagnosed, reevaluated the tissue samples after being trained. The samples
were then categorized as either HER2-low or HER2 IHC 0. The number of patients who were recategorized
as HER2-low among all patients reevaluated was calculated, and information about the patients (such as
age, race, and aspects of disease and treatment) was examined. We also looked at how well the new
HER2 category matched with the first category the patients were given.
What were the findings of this research and what are the implications?
We found that 61.2% f patients with HER2-negative breast cancer were actually HER2-low. We did not
see notable differences in the characteristics of patients with HER2-low and patients with HER2 IHC 0
breast cancer. The majority (79.1%) of HER2 tests that were rescored as HER2-low matched historical
HER2 results. This research helps us understand how many patients have HER2-low breast cancer and
differences between patients with HER2-low and HER2 IHC 0 breast cancer.
Where can I access more information?
ClinicalTrials.gov. Estimation of the prevalence of HER2-low and describe the standard of care, treatment
patterns, and outcome in real-world practice among unresectable and/or metastatic breast cancer patients
with HER2-low status. https://clinicaltrials.gov/ct2/show/NCT04807595
This study is sponsored by AstraZeneca Pharmaceuticals and Dalichi Sankyo Inc. In March 2019, AstraZeneca entered into a global development and commercialization collaboration agreement with Dalichi Sankyo for
trastuzumab deruxtecan (T-Oxd; D0-8201). .....
References: 1. Schettini F, et al. NPJ Breast Cancer. 2021;7(1):1. 2. Nakada T, et al. Chem Pharm Bull (Tokyo). 2019;67(3):173-185. 3. Oglani Y, et al. Clin Cancer Res. 2016;22(20) 5097-5108. 4. Modi 3, et al. J Can
Oncol. 2020;38(17):1887-1896. 5. Modi 3, et al. Presented at San Antonio Breast Cancer Symposium; December 10-14, 2019; San Antonio, Texas. Abstract OT1-07-02. 6. Pauletti G, et al. Oncogene. 1996;13(1):63-72.
7. AstraZeneca. Enhertu significantly improved both progression-free and overall survival in DESTINY-Breast04 trial in patients with HER2-low metastatic breast cancer. Accessed May 4, 2022
https://www.astrazeneca.com/media-centre/press-releases/2122/enhertu-improve-of-and-os-incher2-low-bc.html
• The concordance rate between historical and rescored slides for HER2 status classification was
79.1% (Figure 2)
- Overall, positive agreement was 81.6% and negative agreement was 74.6%
- Overall concordance was similar in the Ventana 4B5 and non-Ventana 4B5 cohorts (79.5% and
78.7%, respectively)
Figure 2. Concordance between rescores and historical scores
Ventana 4B5 assayab
Overall concordance: 163/205 (79.5%)
HER2 IHC 0
Non-Ventana 4B5 assaya.b.c
Overall concordance: 140/178 (78.7%)
K (95% CI): 0.534 (0.406-0.661)
HER2-low
HER2 IHC 0
* (95% CI): 0.572 (0.457-0.686)
HER-low
118/191
60.7
Non-Ventana 4B5 (n=191) 87/134
64.9
Table 2. Patient clinical characteristics
Figure 4. Time to first subsequent treatment
28/56
50.0
HR positive
HR negative
Total
HR+ HER2-low (n=102)
HER2-low
(N=188)
HER2 IHC 0 Total*
(N=95)
HER2-low
(N=291)
(N=46)
HER2 IHC 0 Total"
(N=54)
(N=392)
(N=100)
HR+ HER2 IHC 0 (n=58)
0
20
40
60
80
100.
Time from Initial BC diagnosis to mBC diagnosis, n (%)
<2 years
76 (40.4)
35 (36.8)
116 (39.9)
21 (45.7)
28 (51.9)
49 (49.0)
165 (42.1)
Patients, %
2 to 5 years
39 (20.7)
22 (23.2)
63 (21.6)
14 (30.4)
10 (18.5)
24 (24.0)
87 (22.2)
*Only patients with avaliable HER2 score (HER2-low or HER2 HCD) contributed to prevalence calculations.
Patents with presently unknown HR status included in total category only.
*Ventana and non-Ventana groups based on the rescore results.
>5 years
57 (30.3)
28 (29.5))
85 (29.2)
9 (19.6)
11 (20.4)
20 (20.0)
105 (26.8)
*Includes Hercep Test, Bond Oracle, or unknown.
Not reported/missing
16 (8.5)
10 (10.5)
27 (9.3)
2 (4.3)
5 (9.3)
7 (7.0)
35 (8.9)
HR-HER2-low (n=23)
HR-HER2 IHC 0 (n=31)
HR+ HER2-low (n=28)
HR+ HER2 IHC 0 (n=18)
9.5 (7.5-15.3)
7.0 (6.0-10.5)
7.6 (4.1-8.4)
5.0 (4.2-8.0)
HER2 testing concordance
Location of metastasis/metastases, n (%)
Bone
96 (51.1)
47 (49.5)
150 (51.5)
13 (28.3)
13 (24.1)
26 (26.0)
177 (45.2)
HR+ HER2-low (n=74)
Brain
7 (3.7)
5 (5.3)
13(4.5)
6 (13.0)
4 (7.4)
10 (10.0)
23 (5.9)
Liver
48 (25.5)
30 (31.6)
81 (27.8)
18 (39.1)
14 (25.9)
32 (32.0)
113 (28.8)
Lung
46 (24.5)
23 (24.2)
73 (25.1)
10 (21.7)
17 (31.5)
27 (27.0)
101 (25.8)
Visceral
103 (54.8)
61 (64.2)
171 (58.8)
29 (63.0)
30 (55.6)
59 (59.0)
231 (58.9)
HR+ HER2 IHC 0 (n=40)
HR-HER2 IHC 0 (n=31)
HR-HER2-low (n=23)
Number of metastatic locations, n (%)
1
113 (60.1)
49 (51.6)
162 (55.7)
26 (56.5)
29 (53.7)
55 (55.0)
217 (55.4)
18.6 (8.5-21.3)
13.1 (6.1-15.3)
8.3 (6.0-13.3)
6.4 (3.8-10.0)
7.6 (4.1-9.4)
5.0 (4.2-8.0)
12
18
24
2
36 (19.1)
18 (18.9)
56 (19.2)
7 (15.2)
14 (25.9)
21 (21.0)
77 (19.6)
23
39 (20.7)
20 (29.5)
73 (25.1)
13 (20.3)
11 (20.4)
24 (24.0)
90 (25.0)
Metastatic or locally advanced at Index date, n (%)
All assaysa
Metastatic
169 (89.9)
85 (89.5)
261 (89.7) 43 (93.5)
47 (87.0)
90 (90.0)
351 (89.5)
Kaplan-Meler estimate, median (95% CI), months
*Data for Hire-negative subgroups not reported (no; ie, use of corals intors not indicated for patiens with HR-egative BC).
Figure 5. Overall survival
Overall concordance: 303/383 (79.1%)
Locally advanced
1 (0.5)
0
1 (0.3)
0
2(3.7)
2(2.0)
3 (0.8)
Both
3(1.5)
1 (1.1)
4 (1.4)
1 (2.2)
2 (3.7)
3 (3.0)
7 (1.8)
x (95% CI): 0.554 (0.468-0.640)
HER2-low
HR+ HER2-low (n=150)
Not reported/missing
15 (8.0)
9 (9.5)
25 (8.6)
2 (4.3)
3 (5.6)
5 (5.0)
31 (7.9)
HER2 IHC 0
Stage at Initial BC diagnosis, n (%)
14 (7.4)
6 (6.3)
20 (6.9)
7 (15.2)
7 (13.0)
14 (14.0)
34 (8.7)
Π
62 (33.0)
34 (35.8)
97 (33.3)
11 (23.9)
17 (31.5)
28 (28.0)
125 (31.9)
30 (16.0)
20 (21.1)
52 (17.9)
13 (28.3)
13 (24.1)
26 (26.0)
78 (19.9)
IV
27 (14.4)
14 (14.7)
44 (15.1)
1 (2.2)
9 (16.7)
10 (10.0)
54 (13.8)
Other/not reported/missing
55 (29.3)
21 (22.1)
78 (26.8)
14 (30.4)
8 (14.8)
22 (22.0)
101 (25.8)
HR+ HER2 IHC 0 (n=78)
HR-HER2-low (n=36)
HR-HER2 IHC 0 (n=38)
HR+ HER2-low (n=42)
HR+ HER2 IHC 0 (n=23)
43.9 (38.7-52.7)
41.7 (32.5-53.7)
31.1 (20.6-41.9)
11.5 (8.6-20.5)
66.0 (43.7-NC)
46.1 (32.4-NC)
Positive
agreement
81.6%
Negative
agreement
74.6%
Includes patients with missing HER2 category.
Includes patients with missing HR status.
Reported over the course of patients' metastatic disease.
HR+ HER2-low (n=108)
Index date was the date of mBC diagnosis.
Poster
Plain language
summary
Supplementary material (HER2-low prevalence
by country, overall reported treatments in the
metastatic setting, time to treatment failure)
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Poster presented at ASCO Annual Meeting, June 3-7, 2022; Chicago, IL and online by Dr Giuseppe Viale.
Corresponding author email address: [email protected]
Positive
agreement
85.1%
Negative
agreement
71.4%
Historical HER2-low
*Only patients with available historical scores were included
*Ventana and non-Ventana groups based on the historical score
Includes HercepTest, Bond Oracle, or unknown.
Positive
agreement
78.2%
Negative
agreement
79.6%
Rescored HER2-low
Historical HER2 IHC 0
Rescored HER2 IHC 0
Discussion and limitations
• These data are from a retrospective study, and findings may be impacted by the inherent limitations
associated with this type of data (eg, missing/inaccurate data from health/medical records); as such,
these data should be interpreted carefully
- Furthermore, this data set may not have been optimal for robust analyses of treatment patterns
and outcomes because of the relatively short window of follow-up
⚫ Our data from an unresectable/mBC population have shown a similar HER2-low prevalence (61.2%)
in a HER2-negative cohort as that found in a previous study of a HER2-negative BC population
(60%)1
⚫ Treatment findings are in line with the typical standard of care for HR-positive and HR-negative
subgroups, with endocrine therapy being the most common for HR-positive mBC and chemotherapy
being the most common for HR-negative mBC11
⚫ Survival outcomes are also consistent with previous reports, with no overall difference in OS
observed between HER2-low and HER2 IHC 0 BC,1,12,13 although other studies have shown differing
results 14,15
• Future analyses will investigate stratification of HER2-low status by IHC 1+ vs 2+, which may impact
outcomes 12
*Data for HR-negative subgroups not reported due to small sample size (le, use of CDK416 Inhibitors not indicated for patients with HR-negative BC).
References
1. Schettini F, et al. NPU Breast Cancer. 2021;7(1):1.
2. AstraZeneca. Entertu significantly improved both progression-free and overall
survival in DESTINY-Breast04 trial in patients with HER2-low metastatic breast
cancer. Accessed May 4, 2022. https://www.astrazeneca.com/media-
centre/press-releases/2022/enhertu-improves-pfs-and-os-in-her2-low-bc.html
3. Modi S, et al. J Clin Oncol. 2020;38(17):1887-1896.
4. Dieras V, et al. Presented at: San Antonio Breast Cancer Symposium;
December 7-10, 2021; San Antonio, Texas. Abstract PD8-02.
7. Arteaga CL, et al. Nat Rev Clin Oncol. 2012;9(1):16-32
Pauletti G, et al. Oncogene. 1996;13(1):63-72.
Femandez Al, et al. JAMA Oncol. 2012;217239. [online ahead of print]
10. Landis JR and Koch GG. Blometrics. 1977;33(1):159-174.
11. Lolbl 3, et al. Lancet. 2021:397(10286):1750-1769.
12. Omar AMA, Darwish AMA. J Clin Oncol. 2021;39(suppl 15): Abstract e12515.
13. Gampenrieder SP, et al. Breast Cancer Res. 2021:23(1):112
14. Denkert C, et al. Lancet Oncol. 2021:22(8):1151-1161.
5. Modi S, et al. Presented at: San Antonio Breast Cancer Symposium; December 15. Mutal R, et al. Breast. 2021;60:62-69.
10-14, 2019; San Antonio, Texas. Abstract OT1-07-02.
6. Bardia A, et al. Presented at: San Antonio Breast Cancer Symposium;
December 8-11, 2020; virtual. Abstract OT-03-09.
Abbreviations
COKE
, breast cancer, CDK4/6, cyclin-dependent kinase 4/6; CDK4/6
Inhibitor, HER2, human epidermal growth factor receptor 2; HR, hormone
receptor; IHC, immunohistochemistry; ICH, in situ hybridization;
mBC, metastatic BC, NC, not calculable: 00, overall survival; T-DXd,
trastuzumab deruxtecan.
Acknowledgments
We thank Olga Aleynikova (Jewish General Hospital, McGill University) for her
contributions to this work. We thank the patients who are participating in this
study as well as their familles and caregivers. This study is sponsored by
AstraZeneca Pharmaceuticals and Dalichi Sankyo Inc. In March 2019,
AstraZeneca entered into a global development and commercialization
collaboration agreement with Daiichi Sankyo for trastuzumab deruate can (T-
DXd; D3-8201). Medical writing support was provided by JoAnna Anderson,
PhD, CMPP (Articulate@cience, LLC), and was funded by AstraZeneca.
22
34.4 (25.4-46.4)
HR+ HER2 IHC 0 (n=55)
40.6 (30.3-48.9)
HR-HER2-low (n=35)
29.8 (20.6-41.6)
HR-HER2 IHC 0 (n=36)
11.5 (8.6-20.5)
12
40
60
72
Kaplan-Meier estimate, median (95% CI), monthsView entire presentation