LIVE ESMO GI 2026 Live — top KOL voices, trial buzz & conference slides from Munich View Live Coverage →
KOL Pulse — Trial Profile

SATEEN Trial

Phase II — Sacituzumab govitecan + trastuzumab in HER2+ metastatic breast cancer post-T-DXd. Reported negative primary endpoint at ESMO Breast 2026.

Investigator-initiated (Gilead/Dana-Farber) HER2+ Metastatic Breast Cancer Sacituzumab govitecan + Trastuzumab Phase II ESMO Breast 2026 Investigational Negative Primary Endpoint
Explore Trial Data

Top KOLs Discussing SATEEN

Yakup Ergn
Yakup Ergn
@dr_yakupergun
10,528 impressions
Mali Barbi, MD MSc | Breast & Gyn Oncologist
Mali Barbi, MD MSc | Breast & Gyn Oncologist
@DrBarbiOnc
3,602 impressions
Paolo Tarantino
Paolo Tarantino
@PTarantinoMD
2,616 impressions
Tejas Patil
Tejas Patil
@TejasPatilMD
1,788 impressions
Elisabetta Bonzano MD, PhD
Elisabetta Bonzano MD, PhD
@to_be_elizabeth
1,482 impressions
Abi Siva MD
Abi Siva MD
@AbiSivaMD
1,010 impressions
Presenting Author at ESMO Breast 2026 (#ESMOBreast26)
Paolo Tarantino, MD, PhD
Paolo Tarantino, MD, PhD @PTarantinoMD
Dana-Farber Cancer Institute (Harvard Medical School)
Co-authors: Tarantino P, Yu L, Faggen M, Mahtani R, Yardley D, Wallace E, Kallfel E, et al.

SATEEN Key Slides & Visuals

Trial slides shared by KOLs at ESMO Breast 2026 (#ESMOBreast26). Click any image to expand. OCR text extracted via AWS Textract.

Yakup Ergün
Yakup Ergün @dr_yakupergun
SATEEN
10,528 impressions · 80 likes · 2026-05-08
View on X ↗
[Slide 1]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
2026
ESMO BREAST CANCER
Annual Congress
Sacituzumab govitecan plus trastuzumab in patients with
HER2+ metastatic breast cancer after trastuzumab deruxtecan:
Results from the phase II SATEEN trial
Paolo Tarantino, Luowen Yu. Meredith Faggen, Reshma Mahtani, Denise Yardley, Erin Wallace, Eliza Kallfelz,
Esther Pasternak, Alexander Schubert, Ashka Patel, Tasnim Rahman, Chloe Falls, Sarah Bucher, Joanna
Baginska, Tianyu Li, Harold J. Burstein, Erica L. Mayer, Nabihah Tayob, Sara M. Tolaney and Adrienne G. Waks
Paolo Tarantino, MD, PhD
Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
Dana-Farber
HARVARD
Cancer Institute
MEDICAL SCHOOL
ESMO
09:09
ENG
$0
-
e
8 May 2026
ESMO BREAST CANCER

---

[Slide 2]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Prior taxane, trastuzumab and
ENDPOINTS
T-DXd in any setting
Sacituzumab govitecan
Primary:
Progression on T-DXd not required
10 mg/kg IV D1,8 Q21D
ORR
T-DXd not required to be the
+
Secondary endpoints:
immediate prior line
Trastuzumab Q3W (IV or SC)
- CBR
Patients ineligible for T-DXd allowed
- PFS
to enroll
OS
No prior anti-Trop2 ADC
≤5 prior lines of chemo/ADC *
Brain metastases allowed#
Paolo Tarantino, MD. PhD
Content of this presentation is copyright and responsibility of the author Permission is required for no use
MO
"amended from original protocol which allowed any number of prior lines of treatment # patients with active brain metastases capped at 20% of the study population
ESMO BREAST CANCER

---

[Slide 3]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
PRIMARY ENDPOINT: OBJECTIVE RESPONSE RATE
One confirmed partial response was observed (ORR 3.7%).
The trial did not meet its primary endpoint and was stopped after the 1st stage.
100
PATIENTS (N=27)
80
ORR
3.7% (95% CI: 0.1%-19%)
Best Response
60
PR
CBR > > 18 weeks
14.8% (95% CI: 4%-33%)
SD
% Change of target lesion
40
PD
Symbol Key
20
X
Progression on Prior T-DXd
:
:
X
No Progression on Prior T-DXd
0
HR+ at enrollment
:
:
:
A
:
.
A
HR- at enrollment
Brain Metastasis at enrollment
-20
-40
Prior lines of HER2-directed therapy
574310322671538653422354143
in metastatic setting
Content of this presentation is copynght and responsibility of the author Permission is required for no use
Paolo Tarantino, MD, PhD
ESMO
"percent change target lesion capped a 100% for visualization the maximum observed % change was 330% CBR cirical benefit rate CR Confirmed complete response (PR Confirmed cartial response ORR overall response rate SD: stable disease
ESMO BREAST CANCER

---

[Slide 4]
Rapid Oral session 2
CER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN TRIAL: CONCLUSIONS
SG plus trastuzumab demonstrated an ORR of 3.7% in heavily pre-treated HER2+ metastatic
breast cancer after T-DXd
The trial did not meet its primary endpoint and stopped at the interim analysis for futility
This constitutes the first prospective data for SG + trastuzumab post-T-DXd in HER2+ MBC
Safety was consistent with prior SG trials, although these data emphasize the importance of
growth factor support during SG therapy, particularly among heavily pretreated patients
Biomarker analyses are ongoing to unveil mechanisms of resistance to sequential TOPO1
ADCs and to inform effective post-ADC treatment strategies
Paolo Tarantino, MD. PhD
Content of this presentation is copynght and responsibility of the author Permission is required for to use
ESMO
ESMO BREAST CANCER
Elisabetta Bonzano MD, PhD
Elisabetta Bonzano MD, PhD @to_be_elizabeth
SATEEN
1,482 impressions · 7 likes · 2026-05-08
View on X ↗
[Slide 1]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Stage 1
Stage 2
Prior taxane, trastuzumab and
n=27
n=40
T-DXd in any setting
3/27 patients
7/40 patients
Progression on T-DXd not required
Minimum responders
Minimum responders
T-DXd not required to be the
needed to proceed to
needed to declare
immediate prior line
stage 2
promising antitumor
Patients ineligible for T-DXd allowed
activity
to enroll
No prior anti-Trop2 ADC
STATISTICS: Simon's two-stage design: 27 patients in stage 1, with up to
≤5 prior lines of chemo/ADC *
40 planned overall; 90% power to distinguish an ORR of 25% from a null
Brain metastases allowed#
ORR of 10% using a one-sided 10% type I error.
Paolo Tarantino, MD. PhD
Content of this presentation is copyright and responsibility of the author Permission is required for to use
ESMO
"amended from original protocol which allowed any number of prior lines of treatment # patients with active brain metastases capped at 20% of the study population
ESMO BREAST CANCER

---

[Slide 2]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
PRIMARY ENDPOINT: OBJECTIVE RESPONSE RATE
One confirmed partial response was observed (ORR 3.7%).
The trial did not meet its primary endpoint and was stopped after the 1st stage.
100
PATIENTS (N = 27)
80
ORR
3.7% (95% CI: 0.1%-19%)
Best Response
60
PR
CBR > 18 weeks
14.8% (95% CI: 4%-33%)
SD
% Change of target lesion
40
PD
Symbol Key
20
Progression on Prior T-DXd
:
:
:
No Progression on Prior T-DXd
0
HR+ at enrollment
.
:
:
:
X
:
:
A
:
**
:
***
HR- at enrollment
Brain Metastasis at enrollment
-20
-40
Prior lines of HER2-directed therapy
51743032267153865342235414
3
in metastatic setting
Content of this presentation is copyright and responsibility of the author Permission is required for to use
Paolo Tarantino, MD, PhD
ESMO
"percent change capped if 100% for visialization the maxment observed % change was 330% CBR circal benefit rate CR Confirmed complete response (PR Confirmed partial response ORR (veral response rate so stable disease
ESMO BREAST CANCER

---

[Slide 3]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN: TOXICITY
Grade 2+ TRAEs occurring in >10% of pts:
The most common grade ≥2 treatment-related adverse
events (TRAEs) were anemia, neutropenia, diarrhea
Grade ≥2
Grade 3
Grade 4
and fatigue.
Any TRAE
23 (85%)
13 (48%)
7 (26%)
Anemia
9 patients (33%) required dose modifications due to
16 (59%)
7 (26%)
-
adverse events
Neutropenia
16 (59%)
8 (30%)
8 (30%)
Diarrhea
8 (30%)
5 (19%)
-
There was one grade 5 TRAE (neutropenic sepsis with
-
multi-organ failure) after which mandatory growth
Fatigue
7 (26%)
1 (4%)
factor support after day 8 (+/- after day 1) was
Thrombocytopenia
5 (19%)
-
1 (4%)
implemented in the study.
Alopecia
4 (15%)
-
-
Nausea
3 (11%)
1 (4%)
-
Paolo Tarantino, MD. PhD
Content of this presentation is copyright and responsibility of the author Permission is required for to use
ESMO
Grade 1 AEs were not recorded per protocol
ESMO BREAST CANCER

---

[Slide 4]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN TRIAL: CONCLUSIONS
SG plus trastuzumab demonstrated an ORR of 3.7% in heavily pre-treated HER2+ metastatic
breast cancer after T-DXd
The trial did not meet its primary endpoint and stopped at the interim analysis for futility
This constitutes the first prospective data for SG + trastuzumab post-T-DXd in HER2+ MBC
Safety was consistent with prior SG trials, although these data emphasize the importance of
growth factor support during SG therapy, particularly among heavily pretreated patients
Biomarker analyses are ongoing to unveil mechanisms of resistance to sequential TOPO1
ADCs and to inform effective post-ADC treatment strategies
Paolo Tarantino, MD. PhD
Content of this presentation IN copyright and responsibility of the author Permission is required for re use
ESMO
ESMO 1 BREAST CANCER
Abi Siva MD
Abi Siva MD @AbiSivaMD
SATEEN
1,010 impressions · 9 likes · 2026-05-08
View on X ↗
[Slide 1]
ESMO BREAST CANCER
BERLIN GERMANY
Annual Congress
6-8 MAY 2026
ESMO
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Stage 1
Stage 2
Prior taxane, trastuzumab and
n=27
n=40
T-DXd in any setting
3/27 patients
7/40 patients
Progression on T-DXd not required
Minimum responders
Minimum responders
T-DXd not required to be the
needed to proceed to
needed to declare
immediate prior line
stage 2
promising antitumor
Patients ineligible for T-DXd allowed
activity
to enroll
No prior anti-Trop2 ADC
STATISTICS: Simon's two-stage design: 27 patients in stage 1, with up to
≤5 prior lines of chemo/ADC *
40 planned overall; 90% power to distinguish an ORR of 25% from a null
Brain metastases allowed*
ORR of 10% using a one-sided 10% type I error.
Paolo Tarantino, MD, PhD
Content of this presentation is copynght and responsibility of the author Permission 8 required for re use
ESMO
"amended from original protocol which allowed any number of prior lines of treatment; # patients with active brain metastases capped at 20% of the study population
ESMO BREAST CANCER

---

[Slide 2]
BERLIN GERMANY
6-8 MAY 2026
ESMO
PRIMARY ENDPOINT: OBJECTIVE RESPONSE RATE
One confirmed partial response was observed (ORR 3.7%).
The trial did not meet its primary endpoint and was stopped after the 1st stage.
100
PATIENTS (N = 27)
80
ORR
3.7% (95% CI: 0.1%-19%)
Best Response
60
PR
CBR > 18 weeks
14.8% (95% Cl: 4%-33%)
SD
% Change of target lesion
40
PD
Symbol Key
20
X
Progression on Prior T-DXd
X
No Progression on Prior T-DXd
X
X
X
X
0
HR+ at enrollment
A
HR- at enrollment
Brain Metastasis at enrollment
-20
-40
Prior lines of HER2-directed therapy
51743032267153865342235443
in metastatic setting
Content of this presentation is copyright and responsibility of the author Permission is required for re use
Paolo Tarantino, MD, PhD
ESMO
"percent change in target lesion IS capped at 100% for visualization the maximum observed % change was 330% CBR clinical benefit rate: CCR Confirmed complete response cPR Confirmed cartial response ORR overall response rate SD stable disease
ESMO BREAST CANCER

---

[Slide 3]
BERLIN GERMANY
6-8 MAY 2026
ESMO
SATEEN: SURVIVAL OUTCOMES
Progression-free Survival
Overall Survival
Median PFS:
2.3 months
Median OS: 9.2 months
1.0
1.0
95% CI
(2.0-3.5)
95% CI
(7.6-NR)
Probability of Progression-Free Survival
0.8
0.8
0.6
0.4
Probability of Overall Survival
0.6
0.4
0.2
0.2
0.0
0.0
0
1
2
3
4
5
6
7
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Months from Registration
Months from Registration
Number at risk
Number at risk
All 27
25
17
9
6
3
2
1
All 27 25 24 20 15 13 12 12 11 9 7 6 5 5 4 3 1 1 0
Paolo Tarantino, MD, PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re use
ESMO
ESMO BREAST CANCER
Dr Rishabh Jain
Dr Rishabh Jain @DrRishabhOnco
SATEEN
797 impressions · 9 likes · 2026-05-08
View on X ↗
[Slide 1]
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Prior taxane, trastuzumab and
ENDPOINTS
T-DXd in any setting
Sacituzumab govitecan
Primary:
Progression on T-DXd not required
10 mg/kg IV D1,8 Q21D
ORR
T-DXd not required to be the
+
Secondary endpoints:
immediate prior line
Trastuzumab Q3W (IV or SC)
- CBR
Patients ineligible for T-DXd allowed
- PFS
to enroll
- OS
No prior anti-Trop2 ADC
≤5 prior lines of chemo/ADC*
Brain metastases allowed#
Paolo Tarantino, MD. PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re use
ESMO
"amended from original protocol which allowed any number of prior lines of treatment; # patients with active brain metastases capped at 20% of the study population
ESMO BREAST CANCER

---

[Slide 2]
PRIMARY ENDPOINT: OBJECTIVE RESPONSE RATE
One confirmed partial response was observed (ORR 3.7%).
The trial did not meet its primary endpoint and was stopped after the 1st stage.
100
PATIENTS (N=27)
80
ORR
3.7% (95% CI: 0.1%-19%)
Best Response
60
PR
CBR > 18 weeks
14.8% (95% CI: 4%-33%)
SD
% Change of target lesion
40
PD
Symbol Key
20
Progression on Prior T-DXd
X
No Progression on Prior T-DXd
0
HR+ at enrollment
:
:
***
:
***
:
:
**
A
:
:
***
***
HR- at enrollment
Brain Metastasis at enrollment
-20
-
-40
Prior lines of HER2-directed therapy
51743032267153865342235443
in metastatic setting
Content of this presentation is copyright and responsibility of the author Permission 15 required for re use
Paolo Tarantino, MD, PhD
ESMO
"percent change n target term capped at 100% for visualization: the maximum observed % change was 330% CBR circal benefit rate: CR Confirmed complete response (PR Confirmed certify response: ORR overan response rate so stable disease
ESMO BREAST CANCER

---

[Slide 3]
SATEEN: TOXICITY
Grade 2+ TRAEs occurring in >10% of pts:
The most common grade ≥2 treatment-related adverse
events (TRAEs) were anemia, neutropenia, diarrhea
Grade ≥2
Grade 3
Grade 4
and fatigue.
Any TRAE
23 (85%)
13 (48%)
7 (26%)
Anemia
9 patients (33%) required dose modifications due to
16 (59%)
7 (26%)
-
adverse events
Neutropenia
16 (59%)
8 (30%)
8 (30%)
Diarrhea
8 (30%)
5 (19%)
-
Fatigue
7 (26%)
1 (4%)
-
Thrombocytopenia
5 (19%)
-
1 (4%)
Alopecia
4 (15%)
-
-
Nausea
3 (11%)
1 (4%)
-
Paolo Tarantino, MD, PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re use
ESMO
Grade 1 AEs were not recorded per protocol

---

[Slide 4]
SATEEN TRIAL: CONCLUSIONS
SG plus trastuzumab demonstrated an ORR of 3.7% in heavily pre-treated HER2+ metastatic
breast cancer after T-DXd
The trial did not meet its primary endpoint and stopped at the interim analysis for futility
This constitutes the first prospective data for SG + trastuzumab post-T-DXd in HER2+ MBC
Safety was consistent with prior SG trials, although these data emphasize the importance of
growth factor support during SG therapy, particularly among heavily pretreated patients
Biomarker analyses are ongoing to unveil mechanisms of resistance to sequential TOPO1
ADCs and to inform effective post-ADC treatment strategies
Paolo Tarantino, MD. PhD
Content of this presentation is copyright and responsibility of the author Permission IS required for re use
ESMO
ESMO BREAST CANCER
Kazuki Nozawa, MD
Kazuki Nozawa, MD @kazuki_nozawa
SATEEN
771 impressions · 8 likes · 2026-05-08
View on X ↗
[Slide 1]
2026
ESMO BREAST CANCER
Annual Congress
Sacituzumab govitecan plus trastuzumab in patients with
HER2+ metastatic breast cancer after trastuzumab deruxtecan:
Results from the phase II SATEEN trial
Paolo Tarantino, Luowen Yu, Meredith Faggen, Reshma Mahtani, Denise Yardley, Erin Wallace, Eliza Kallfelz,
Esther Pasternak, Alexander Schubert, Ashka Patel, Tasnim Rahman, Chloe Falls, Sarah Bucher, Joanna
Baginska, Tianyu Li, Harold J. Burstein, Erica L. Mayer, Nabihah Tayob, Sara M. Tolaney and Adrienne G. Waks
Paolo Tarantino, MD, PhD
Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
Dana-Farber
HARVARD
Cancer Institute
MEDICAL SCHOOL
ESMO

---

[Slide 2]
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Prior taxane, trastuzumab and
ENDPOINTS
T-DXd in any setting
Sacituzumab govitecan
Primary:
Progression on T-DXd not required
10 mg/kg IV D1,8 Q21D
- ORR
T-DXd not required to be the
+
Secondary endpoints:
immediate prior line
Trastuzumab Q3W (IV or SC)
- CBR
Patients ineligible for T-DXd allowed
- PFS
to enroll
- OS
No prior anti-Trop2 ADC
≤5 prior lines of chemo/ADC*
Brain metastases allowed#
Paolo Tarantino, MD, PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re use
ESMO
"amended from original protocol which allowed any number of prior lines of treatment # patients with active brain metastases capped at 20% of the study population

---

[Slide 3]
PRIMARY ENDPOINT: OBJECTIVE RESPONSE RATE
One confirmed partial response was observed (ORR 3.7%).
The trial did not meet its primary endpoint and was stopped after the 1st stage.
100
PATIENTS (N = 27)
80
ORR
3.7% (95% CI: 0.1%-19%)
Best Response
60
PR
CBR > 18 weeks
14.8% (95% CI: 4%-33%)
SD
% Change of target lesion
40
PD
Symbol Key
20
X
Progression on Prior T-DXd
X
No Progression on Prior T-DXd
X
X
0
HR+ at enrollment
X
X
X
A
A
A
A
HR- at enrollment
Brain Metastasis at enrollment
-20
-40
Prior lines of HER2-directed therapy
51743032267153865342235443
in metastatic setting
Content of this presentation is copyright and responsibility of the author Permission is required for re use
Paolo Tarantino, MD, PhD
ESMO
"percent change in target lesion is capped at 100% for visualization the maximum observed % change was 330% CBR clinical benefit rate CCR Confirmed complete response CPR Confirmed partial response ORR overall response rate SD stable disease

---

[Slide 4]
SATEEN: TOXICITY
Grade 2+ TRAEs occurring in >10% of pts:
The most common grade ≥2 treatment-related adverse
events (TRAEs) were anemia, neutropenia, diarrhea
Grade ≥2
Grade 3
Grade 4
and fatigue.
Any TRAE
23 (85%)
13 (48%)
7 (26%)
Anemia
9 patients (33%) required dose modifications due to
16 (59%)
7 (26%)
-
adverse events
Neutropenia
16 (59%)
8 (30%)
8 (30%)
Diarrhea
8 (30%)
5 (19%)
-
Fatigue
7 (26%)
1 (4%)
-
Thrombocytopenia
5 (19%)
-
1 (4%)
Alopecia
4 (15%)
-
-
Nausea
3 (11%)
1 (4%)
-
Paolo Tarantino, MD, PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re use
ESMO
Grade 1 AEs were not recorded per protocol
Hope Rugo
Hope Rugo @hoperugo
SATEEN
728 impressions · 17 likes · 2026-05-08
View on X ↗
[Slide 1]
SATEEN: DESIGN
Phase 2, single arm, investigator-initiated, multicenter trial
Advanced HER2+ cancer
Prior taxane, trastuzumab and
ENDPOINTS
T-DXd in any setting
Sacituzumab govitecan
Primary:
Progression on T-DXd not required
10 mg/kg IV D1,8 Q21D
- ORR
T-DXd not required to be the
+
immediate prior line
Secondary endpoints:
Patients ineligible for T-DXd allowed
Trastuzumab Q3W (IV or SC)
CBR
to enroll
PFS
- OS
No prior anti-Trop2 ADC
≤5 prior lines of chemo/ADC*
Brain metastases allowed#
Paolo Tarantino, MD, PhD
Content of this presentation is copyright and responsibility of the author Permission is required for re-use
ESMO
amended from original protocol which allowed any number of prior lines of treatment # patients with active brain metastases capped at 20% of the study population

SATEEN Top Tweets

Yakup Ergün @dr_yakupergun
10,528 imp · 80 likes · 2026-05-08
#ESMOBreast26 SATEEN is negative, but highly informative. Mechanistically, SG + trastuzumab was a reasonable idea after T-DXd, especially for tumors with HER2 loss or reduced HER2 dependency. But the efficacy was very limited. ADC resistance is layered: target expression, https://t.co/nq28jCfEDH
View on X ↗
3,602 imp · 20 likes · 2026-05-10
Two prospective phase II trials at #ESMOBC26 just settled something the field has been debating retrospectively. #SATEEN (LBA4): #saci+ #trastuzumab after prior T-DXd in HER2+ MBC. ORR 3.7%. One response in 27 patients. Median PFS 2.3 months. Stopped for futility. #HER3_DXd:
View on X ↗
Tejas Patil @TejasPatilMD
1,788 imp · 13 likes · 2026-05-11
⭐️Everything in this post is directly relevant to #lungcancer as well. #SATEEN answers the value of using sequential ADCs with a topoisomerase payload. ⚠️The answer.. There minimal to no value in sequencing ADCs with the same payload. @lcsmchat @OncoAlert @OncogeneCancer https://t.co/cSDL1bZg1j
View on X ↗
Elisabetta Bonzano MD, PhD @to_be_elizabeth
1,482 imp · 7 likes · 2026-05-08
📌 Results from the phase II SATEEN trial Efficacy and safety of sacituzumab govitecan plus trastuzumab in patients with HER2+ metastatic breast cancer after prior trastuzumab deruxtecan (T-DXd) @PTarantinoMD #ESMOBreast26 @OncoAlert #OncoAlertAF https://t.co/cIZv8ZU0t1
View on X ↗
Paolo Tarantino @PTarantinoMD
1,405 imp · 25 likes · 2026-04-15
It will be the first prospective data of SG after T-DXd and the first data of SG in HER2+ disease. We’re very glad to have the opportunity to present it at ESMO Breast, and hope that the results will inform drug development in the challenging setting of T-DXd-refractory MBC! 💪 https://t.co/0XwZtkPpQS
View on X ↗
Paolo Tarantino @PTarantinoMD
1,211 imp · 11 likes · 2026-05-08
Great perspective by @GrindaThomas on the #SATEEN and #HER3DXd post-ADC trials, both providing prospective data on TOPO1 ADCs after prior T-DXd. Switching ADC target does not seem to be the answer to overcome resistance, if the payload has a similar mechanism of action. @myESMO https://t.co/qOcPOacLww
View on X ↗
Abi Siva MD @AbiSivaMD
1,010 imp · 9 likes · 2026-05-08
SATEEN: SG showed poor activity in HER2+ MBC post taxanes, trastuzumab, and T-DXd (ORR 3.7%, short PFS). Biomarker work may help identify the rare responders to a second TROP2 ADC, a major unanswered question in breast cancer. #ESMOBreast26 https://t.co/jWIKkz2Ihe
View on X ↗
Sara Tolaney @stolaney1
798 imp · 22 likes · 2026-05-08
SATEEN beautifully presented by @PTarantinoMD SG+ Trastuzumab in pts with HER2+ MBC post TDXd 2-stage single-arm ph 2 trial, didn't get to 2nd stage Median 5 prior lines ORR 3.7% (1 PR in 27 pts) CBR 14.8% #ESMOBreast26 @OncoAlert @DFCI_BreastOnc
View on X ↗

Top Discussion Threads

Highest-engagement tweets about this trial, ranked by KOL discussant count (replies + quote-tweets). Replies in green, quote-tweets in blue. Wall Street, stock-promo, and non-substantive replies excluded.

4 active discussion threads
0 KOL discussants
Yakup Ergün
Yakup Ergün
@dr_yakupergun

#ESMOBreast26 SATEEN is negative, but highly informative. Mechanistically, SG + trastuzumab was a reasonable idea after T-DXd, especially for tumors with HER2 loss or reduced HER2 dependency. But the efficacy was very limited. ADC resistance is layered: target expression, https

👁 10.5K ♡ 80 ↻ 29 💬 3 replies 🔁 2 quotes 2026-05-08
↻ Amplified by 12 KOLs
@CharonCalypso@KarolinaLarsso5@Icro_Meattini@Stefani19753108@Rick_Villalobos@GlopesMd@pablojaramartin@siegfrinde+4
Hope Rugo
Hope Rugo
@hoperugo

@myESMO #ESMOBC26 @PTarantinoMD SATEEN trial SG +T in 27 TDXd rx’d HER2+ pts w/ MBC. ORR 3.7% in very heavily preRx (5+ lines). Chemo resistant dse w/ topo1 inh ADC post #’s of effective HER2 targeted Rx - nothing works here - impossible task! Nice presentation! @OncoAlert https:

👁 728 ♡ 17 ↻ 9 💬 0 replies 🔁 0 quotes 2026-05-08
↻ Amplified by 8 KOLs
@DFCI_BreastOnc@JaniceTNBCmets@Icro_Meattini@Stefani19753108@PTarantinoMD@OncoReporte@weoncologists@drsarahsam
Elisabetta Bonzano MD, PhD
Elisabetta Bonzano MD, PhD
@to_be_elizabeth

📌 Results from the phase II SATEEN trial Efficacy and safety of sacituzumab govitecan plus trastuzumab in patients with HER2+ metastatic breast cancer after prior trastuzumab deruxtecan (T-DXd) @PTarantinoMD #ESMOBreast26 @OncoAlert #OncoAlertAF https://t.co/cIZv8ZU0t1

👁 1.5K ♡ 7 ↻ 7 💬 0 replies 🔁 0 quotes 2026-05-08
↻ Amplified by 6 KOLs
@anti_breastc@DFCI_BreastOnc@YoichiKoyamaMD@Stefani19753108@OncoReporte@weoncologists
Sara Tolaney
Sara Tolaney
@stolaney1

SATEEN beautifully presented by @PTarantinoMD SG+ Trastuzumab in pts with HER2+ MBC post TDXd 2-stage single-arm ph 2 trial, didn't get to 2nd stage Median 5 prior lines ORR 3.7% (1 PR in 27 pts) CBR 14.8% #ESMOBreast26 @OncoAlert @DFCI_BreastOnc

👁 798 ♡ 22 ↻ 7 💬 0 replies 🔁 0 quotes 2026-05-08
↻ Amplified by 6 KOLs
@DFCI_BreastOnc@JaniceTNBCmets@ValenzaCarmine@PTarantinoMD@OncoReporte@weoncologists

About the SATEEN Trial

SATEEN was a Phase II investigator-initiated trial evaluating sacituzumab govitecan (SG, anti-Trop-2 antibody-drug conjugate) combined with trastuzumab in patients with HER2-positive metastatic breast cancer who had progressed after prior taxane, trastuzumab, and trastuzumab deruxtecan (T-DXd). Presented at ESMO Breast 2026, the trial was designed to test whether re-targeting Trop-2 with SG plus continued HER2 blockade could rescue activity in heavily pretreated patients with limited remaining options. The primary endpoint of objective response rate was not met, with the trial reporting an ORR of 3.7% and short progression-free survival of approximately 2.3 months. Despite the negative result, KOLs noted the trial provides important prospective data on Trop-2 ADCs after T-DXd progression and may inform future biomarker-driven sequencing strategies.

SATEEN Methodology & Results

Population: Patients with HER2-positive metastatic breast cancer who had received prior taxane chemotherapy, trastuzumab, and T-DXd, with measurable disease and progression on most recent therapy.

Interventions: Sacituzumab govitecan (SG, anti-Trop-2 ADC with SN-38 payload) administered intravenously in combination with trastuzumab as continued HER2-directed therapy.

Endpoints: Primary endpoint: objective response rate (ORR) by RECIST 1.1. Secondary endpoints included progression-free survival, overall survival, duration of response, and safety/tolerability.

Efficacy — ORR 3.7% · PFS 2.3 months · OS 9.2 months

The trial did not meet its primary endpoint. SG plus trastuzumab demonstrated limited efficacy in this heavily pretreated HER2+ population: ORR of 3.7%, median PFS of approximately 2.3 months, and median OS of 9.2 months. KOL commentary highlighted that mechanistic overlap between T-DXd and SG (both targeting topoisomerase I via different antibody-payload combinations) likely contributed to the lack of activity post-T-DXd progression.

Safety & Tolerability — Manageable safety profile, no new signals

The combination demonstrated a manageable safety profile consistent with the known toxicities of each individual agent. No new safety signals emerged with the SG + trastuzumab combination. Adverse events were primarily attributable to SG, with neutropenia and gastrointestinal toxicity being the most common. Discontinuations due to toxicity were limited.

Clinical Implications

⚠️ SATEEN is an investigational trial that did not meet its primary endpoint and does not support a new clinical indication for SG plus trastuzumab in HER2+ MBC after T-DXd. The negative result highlights the challenge of sequencing topoisomerase-I-targeting ADCs and reinforces the need for biomarker-driven patient selection — particularly Trop-2 expression and tumor heterogeneity assessment — when designing post-T-DXd salvage strategies. KOLs (notably Dr. Yakup Ergün, Dr. Sara Tolaney, Dr. Hope Rugo, Dr. Paolo Tarantino) emphasized this trial's value in providing prospective data that informs the broader question of ADC sequencing in HER2+ disease.

SATEEN in the News

Key KOL Sentiments — SATEEN

HandleNameSentimentTweet (excerpt)Imp.
@PTarantinoMD Paolo Tarantino Positive It will be the first prospective data of SG after T-DXd and the first data of SG in HER2+ disease. We’re very glad to ha… 1,405
@dr_yakupergun Yakup Ergün Neutral #ESMOBreast26 SATEEN is negative, but highly informative. Mechanistically, SG + trastuzumab was a reasonable idea after… 10,528
@DrBarbiOnc Mali Barbi, MD MSc | Breast & Gyn Oncolo Neutral Two prospective phase II trials at #ESMOBC26 just settled something the field has been debating retrospectively. #SATEE… 3,602
@TejasPatilMD Tejas Patil Neutral ⭐️Everything in this post is directly relevant to #lungcancer as well. #SATEEN answers the value of using sequential ADC… 1,788
@to_be_elizabeth Elisabetta Bonzano MD, PhD Neutral 📌 Results from the phase II SATEEN trial Efficacy and safety of sacituzumab govitecan plus trastuzumab in patients with … 1,482