ENHERTU® (fam-trastuzumab deruxtecan-nxki) Additional Analyses Further Reinforce Ground-breaking Efficacy in Patients With HER2-positive Metastatic Breast Cancer

Rhea-AI Summary

New data from the DESTINY-Breast03 trial presented at SABCS 2021 show that AstraZeneca and Daiichi Sankyo’s ENHERTU demonstrated superior progression-free survival (PFS) and objective response rate (ORR) in HER2-positive breast cancer patients compared to T-DM1. In a subgroup with stable brain metastases, ENHERTU achieved a median PFS of 15 months versus 3 months for T-DM1. Overall, the confirmed ORR was 67.4% for ENHERTU against 20.5% for T-DM1. ENHERTU is gaining recognition for its potential to improve treatment options for patients with previously treated HER2-positive metastatic breast cancer.

Positive

• ENHERTU shows 67.4% confirmed ORR compared to 20.5% for T-DM1.
• Median PFS of 15 months with ENHERTU in patients with stable brain metastases.
• ENHERTU may become the new standard of care for HER2-positive metastatic breast cancer.

Negative

• ENTERTU reports interstitial lung disease in 10.5% of patients.
• Serious adverse reactions occurred in 20% of patients receiving ENHERTU.

New DESTINY-Breast03 data presented at SABCS 2021 showed AstraZeneca and Daiichi Sankyo’s ENHERTU demonstrated a similar benefit in patient subgroups, including in patients with stable brain metastases, versus T-DM1

WILMINGTON, Del.--(BUSINESS WIRE)-- New results from the DESTINY-Breast03 Phase III trial showed that ENHERTU^® (fam-trastuzumab deruxtecan-nxki) demonstrated a higher progression-free survival (PFS) and objective response rate (ORR) in pre-specified patient subgroups compared to trastuzumab emtansine (T-DM1) in patients with HER2 positive unresectable and/or metastatic breast cancer previously treated with trastuzumab and a taxane.

ENHERTU is a HER2-directed antibody drug conjugate (ADC) being jointly developed by AstraZeneca and Daiichi Sankyo Company, Limited (hereafter, Daiichi Sankyo).

A similar PFS and ORR benefit was observed in exploratory analyses in patients defined by stable brain metastases, hormone receptor status, number of prior lines of therapy, prior pertuzumab treatment, or status of visceral metastasis. Results were presented as an oral presentation at the 2021 San Antonio Breast Cancer Symposium (SABCS).

In patients with stable brain metastases at baseline, treatment with ENHERTU resulted in higher PFS compared to T-DM1 (PFS by blinded independent central review (BICR) hazard ratio [HR] = 0.25; 95% confidence interval [CI]: 0.13-0.45). Additionally, in this subgroup, ENHERTU improved PFS to a median of 15 months versus 3 months for T-DM1.

Sarah Hurvitz, MD, MD, FACP, medical oncologist, professor of medicine, and director of the Breast Cancer Clinical Trials Program in the division of hematology-oncology at the David Geffen School of Medicine at UCLA, and medical director for the Clinical Research Unit at the UCLA Jonsson Comprehensive Cancer Center in Santa Monica, CA, said: “The main goals in the treatment of HER2-positive metastatic breast cancer, including those with stable brain metastases, are to improve symptoms, stabilize or reduce tumor size and improve overall survival. The higher progression-free survival seen in DESTINY-Breast03 in the subgroup of patients with stable brain metastases are encouraging, and underscores the excitement around another potential treatment option for patients who have experienced disease progression on currently available therapies.”

Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca, said: “More treatment options are needed to delay progression and extend survival for patients with HER2-positive metastatic breast cancer who develop brain metastases. These additional analyses from DESTINY-Breast03 reinforce the potential of ENHERTU with similar benefits in the different subgroups.”

Ken Takeshita, Global Head, R&D, Daiichi Sankyo, said: “These additional analyses from DESTINY-Breast03 continue to demonstrate the benefit of ENHERTU compared to T-DM1 in patient subgroups, including 15-month progression-free survival in those with stable brain metastases, illustrating the potential of this treatment to become the new standard of care in patients with previously treated HER2-positive metastatic breast cancer. These data will support our ongoing conversations with global health authorities to realize our commitment to bring ENHERTU to patients with previously treated HER2-positive metastatic breast cancer earlier in the metastatic setting.”

Between 30 to 50% of patients with HER2-positive metastatic breast cancer will develop brain metastases, and while increased availability of HER2 therapies has improved systemic disease control, prognosis following the development of brain metastases remains poor.^1-5

Confirmed ORR for patients with stable brain metastases at baseline was 67.4% with ENHERTU versus 20.5% with T-DM1. A retrospective, non-prespecified evaluation of intracranial response among patients with stable brain metastases who received scans at baseline provided preliminary evidence that treatment with ENHERTU is associated with intracranial tumor response and reduction in Central Nervous System disease with 10 (27.8%) complete responses (CR) and 13 (36.1%) partial responses (PR) compared to one (2.8%) CR and 11 (30.6%) PRs in those treated with T-DM1.

Summary of DESTINY-Breast03 subgroup analyses

	Median PFS by BICR (95% CI)		Median ORR % (95% CI)
	ENHERTU	T-DM1	ENHERTU	T-DM1
All Patients (n=524)	NE (18.5-NE)	6.8 (5.6-8.2)	79.7	34.2
	HR=0.2840 (0.2165-0.3727)		45.5 (37.6-53.4)a
Hormone Receptor
Positive (n=272)	22.4 (17.7-NE)	6.9 (4.2-9.8)	78.2	30.9
	HR=0.3191 (0.2217-0.4594)		47.3 (36.1-58.4)a
Negative (n=248)	NE (18.0-NE)	6.8 (5.4-8.3)	81.7	38.5
	HR=0.2965 (0.2008-0.4378)		43.2 (31.5-55.0)a
Prior Pertuzumab
Yes (n=320)	NE (18.5-NE)	6.8 (5.4-8.3)	79.6	32.9
	HR=0.3050 (0.2185-0.4257)		46.7 (36.5-56.9)a
No (n=204)	NE (16.5-NE)	7.0 (4.2-9.7)	79.8	36.2
	HR=0.2999 (0.1924-0.4675)		43.6 (30.5-56.7)a
Visceral Disease
Yes (n=384)	22.2 (16.5-NE)	5.7 (4.2-7.0)	77.4	29.1
	HR=0.2806 (0.2083-0.3779)		48.3 (39.1-57.6)a
No (n=140)	NE (NE-NE)	11.3 (6.8-NE)	86.4	47.3
	HR=0.3157 (0.1718-0.5804)		39.1 (23.6-54.6)a
Prior Lines of Therapya
0-1 (n=258)	22.4 (17.9-NE)	8.0 (5.7-9.7)	75.0	35.7
	HR=0.3302 (0.2275-0.4794)		39.3 (27.3-51.2)a
≥2 (n=266)	NE (16.8-NE)	5.6 (4.2-7.1)	84.5	32.8
	HR=0.2828 (0.1933-0.4136)		51.6 (40.9-62.4)a
Brain Metastases at Baseline
Yes (n=82)	15.0 (12.5-22.2)	3.0 (2.8-5.8)	67.4	20.5
	HR=0.2465 (0.1341-0.4529)		46.9 (25.6-68.3)a
No (n=442)	NE (22.4-NE)	7.1 (5.6-9.7)	82.1	36.6
	HR=0.2971 (0.2199-0.4014)		45.5 (36.9-54.1)a

CI, confidence interval; HR, hazard ratio; PFS, progression-free survival; NE, not estimable; ORR, objective response rate

^a Absolute ORR Difference, % [ENHERTU-T-DM1]

^b Prior lines of therapy in the metastatic setting. Rapid progressors on (neo)adjuvant therapy was included as one line of treatment. Line of therapy does not include endocrine therapy.

The safety profile of the most common adverse events with ENHERTU in DESTINY-Breast03 remains consistent with previous clinical trials of ENHERTU in breast cancer with no new safety concerns identified. Adjudicated drug-related interstitial lung disease or pneumonitis was reported in 27 patients (10.5%) treated with ENHERTU and five patients (1.9%) treated with T-DM1 overall, with no Grade 4 or 5 events.

Based on the primary results of DESTINY-Breast03, ENHERTU received its fourth Breakthrough Therapy Designation (BTD) in the U.S. for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received one or more prior anti-HER2 based regimens in September 2021.

ENHERTU is approved for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in more than 30 countries based on the results from the DESTINY-Breast01 trial.

ENHERTU is being further assessed in a comprehensive clinical development program evaluating efficacy and safety across multiple HER2-targetable cancers, including breast, gastric, lung and colorectal cancers.

Important Safety Information

Indications
ENHERTU is a HER2-directed antibody and topoisomerase inhibitor conjugate indicated for the treatment of adult patients with:

• Unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting.
  
  This indication is approved under accelerated approval based on tumor response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

• Locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma who have received a prior trastuzumab-based regimen.

WARNING: INTERSTITIAL LUNG DISEASE and EMBRYO-FETAL TOXICITY Interstitial lung disease (ILD) and pneumonitis, including fatal cases, have been reported with ENHERTU. Monitor for and promptly investigate signs and symptoms including cough, dyspnea, fever, and other new or worsening respiratory symptoms. Permanently discontinue ENHERTU in all patients with Grade 2 or higher ILD/pneumonitis. Advise patients of the risk and to immediately report symptoms. Exposure to ENHERTU during pregnancy can cause embryo-fetal harm. Advise patients of these risks and the need for effective contraception.

Contraindications
None.

Warnings and Precautions
Severe, life-threatening, or fatal interstitial lung disease (ILD), including pneumonitis, can occur in patients treated with ENHERTU. Advise patients to immediately report cough, dyspnea, fever, and/or any new or worsening respiratory symptoms. Monitor patients for signs and symptoms of ILD. Promptly investigate evidence of ILD. Evaluate patients with suspected ILD by radiographic imaging. Consider consultation with a pulmonologist. For asymptomatic ILD/pneumonitis (Grade 1), interrupt ENHERTU until resolved to Grade 0, then if resolved in ≤28 days from date of onset, maintain dose. If resolved in >28 days from date of onset, reduce dose one level. Consider corticosteroid treatment as soon as ILD/pneumonitis is suspected (e.g., ≥0.5 mg/kg/day prednisolone or equivalent). For symptomatic ILD/pneumonitis (Grade 2 or greater), permanently discontinue ENHERTU. Promptly initiate systemic corticosteroid treatment as soon as ILD/pneumonitis is suspected (e.g., ≥1 mg/kg/day prednisolone or equivalent) and continue for at least 14 days followed by gradual taper for at least 4 weeks.

Metastatic Breast Cancer
In clinical studies, of the 234 patients with unresectable or metastatic HER2-positive breast cancer treated with ENHERTU 5.4 mg/kg, ILD occurred in 9% of patients. Fatal outcomes due to ILD and/or pneumonitis occurred in 2.6% of patients treated with ENHERTU. Median time to first onset was 4.1 months (range: 1.2 to 8.3).

Locally Advanced or Metastatic Gastric Cancer
In DESTINY-Gastric01, of the 125 patients with locally advanced or metastatic HER2‑positive gastric or GEJ adenocarcinoma treated with ENHERTU 6.4 mg/kg, ILD occurred in 10% of patients. Median time to first onset was 2.8 months (range: 1.2 to 21.0).

Neutropenia
Severe neutropenia, including febrile neutropenia, can occur in patients treated with ENHERTU. Monitor complete blood counts prior to initiation of ENHERTU and prior to each dose, and as clinically indicated. For Grade 3 neutropenia (Absolute Neutrophil Count [ANC] <1.0 to 0.5 x 10⁹/L) interrupt ENHERTU until resolved to Grade 2 or less, then maintain dose. For Grade 4 neutropenia (ANC <0.5 x 10⁹/L) interrupt ENHERTU until resolved to Grade 2 or less. Reduce dose by one level. For febrile neutropenia (ANC <1.0 x 10⁹/L and temperature >38.3ºC or a sustained temperature of ≥38ºC for more than 1 hour), interrupt ENHERTU until resolved. Reduce dose by one level.

Metastatic Breast Cancer
In clinical studies, of the 234 patients with unresectable or metastatic HER2-positive breast cancer who received ENHERTU 5.4mg/kg, a decrease in neutrophil count was reported in 62% of patients. Sixteen percent had Grade 3 or 4 decrease in neutrophil count. Median time to first onset of decreased neutrophil count was 23 days (range: 6 to 547). Febrile neutropenia was reported in 1.7% of patients.

Locally Advanced or Metastatic Gastric Cancer
In DESTINY-Gastric01, of the 125 patients with locally advanced or metastatic HER2‑positive gastric or GEJ adenocarcinoma treated with ENHERTU 6.4 mg/kg, a decrease in neutrophil count was reported in 72% of patients. Fifty-one percent had Grade 3 or 4 decreased neutrophil count. Median time to first onset of decreased neutrophil count was 16 days (range: 4 to 187). Febrile neutropenia was reported in 4.8% of patients.

Left Ventricular Dysfunction
Patients treated with ENHERTU may be at increased risk of developing left ventricular dysfunction. Left ventricular ejection fraction (LVEF) decrease has been observed with anti-HER2 therapies, including ENHERTU. In the 234 patients with unresectable or metastatic HER2-positive breast cancer who received ENHERTU, two cases (0.9%) of asymptomatic LVEF decrease were reported. In DESTINY-Gastric01, of the 125 patients with locally advanced or metastatic HER2‑positive gastric or GEJ adenocarcinoma treated with ENHERTU 6.4 mg/kg, no clinical adverse events of heart failure were reported; however, on echocardiography, 8% were found to have asymptomatic Grade 2 decrease in LVEF. Treatment with ENHERTU has not been studied in patients with a history of clinically significant cardiac disease or LVEF <50% prior to initiation of treatment.

Assess LVEF prior to initiation of ENHERTU and at regular intervals during treatment as clinically indicated. When LVEF is >45% and absolute decrease from baseline is 10-20%, continue treatment with ENHERTU. When LVEF is 40-45% and absolute decrease from baseline is <10%, continue treatment with ENHERTU and repeat LVEF assessment within 3 weeks. When LVEF is 40-45% and absolute decrease from baseline is 10-20%, interrupt ENHERTU and repeat LVEF assessment within 3 weeks. If LVEF has not recovered to within 10% from baseline, permanently discontinue ENHERTU. If LVEF recovers to within 10% from baseline, resume treatment with ENHERTU at the same dose. When LVEF is <40% or absolute decrease from baseline is >20%, interrupt ENHERTU and repeat LVEF assessment within 3 weeks. If LVEF of <40% or absolute decrease from baseline of >20% is confirmed, permanently discontinue ENHERTU. Permanently discontinue ENHERTU in patients with symptomatic congestive heart failure.

Embryo-Fetal Toxicity
ENHERTU can cause fetal harm when administered to a pregnant woman. Advise patients of the potential risks to a fetus. Verify the pregnancy status of females of reproductive potential prior to the initiation of ENHERTU. Advise females of reproductive potential to use effective contraception during treatment and for at least 7 months following the last dose of ENHERTU. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with ENHERTU and for at least 4 months after the last dose of ENHERTU.

Additional Dose Modifications

Thrombocytopenia
For Grade 3 thrombocytopenia (platelets <50 to 25 x 10⁹/L) interrupt ENHERTU until resolved to Grade 1 or less, then maintain dose. For Grade 4 thrombocytopenia (platelets <25 x 10⁹/L) interrupt ENHERTU until resolved to Grade 1 or less. Reduce dose by one level.

Adverse Reactions
Metastatic Breast Cancer

The safety of ENHERTU was evaluated in a pooled analysis of 234 patients with unresectable or metastatic HER2-positive breast cancer who received at least one dose of ENHERTU 5.4 mg/kg in DESTINY-Breast01 and Study DS8201-A-J101. ENHERTU was administered by intravenous infusion once every three weeks. The median duration of treatment was 7 months (range: 0.7 to 31).

Serious adverse reactions occurred in 20% of patients receiving ENHERTU. Serious adverse reactions in >1% of patients who received ENHERTU were interstitial lung disease, pneumonia, vomiting, nausea, cellulitis, hypokalemia, and intestinal obstruction. Fatalities due to adverse reactions occurred in 4.3% of patients including interstitial lung disease (2.6%), and the following events occurred in one patient each (0.4%): acute hepatic failure/acute kidney injury, general physical health deterioration, pneumonia, and hemorrhagic shock.

ENHERTU was permanently discontinued in 9% of patients, of which ILD accounted for 6%. Dose interruptions due to adverse reactions occurred in 33% of patients treated with ENHERTU. The most frequent adverse reactions (>2%) associated with dose interruption were neutropenia, anemia, thrombocytopenia, leukopenia, upper respiratory tract infection, fatigue, nausea, and ILD. Dose reductions occurred in 18% of patients treated with ENHERTU. The most frequent adverse reactions (>2%) associated with dose reduction were fatigue, nausea, and neutropenia.

The most common (≥20%) adverse reactions, including laboratory abnormalities, were nausea (79%), white blood cell count decreased (70%), hemoglobin decreased (70%), neutrophil count decreased (62%), fatigue (59%), vomiting (47%), alopecia (46%), aspartate aminotransferase increased (41%), alanine aminotransferase increased (38%), platelet count decreased (37%), constipation (35%), decreased appetite (32%), anemia (31%), diarrhea (29%), hypokalemia (26%), and cough (20%).

Locally Advanced or Metastatic Gastric Cancer

The safety of ENHERTU was evaluated in 187 patients with locally advanced or metastatic HER2‑positive gastric or GEJ adenocarcinoma in DESTINY‑Gastric01. Patients intravenously received at least one dose of either ENHERTU (N=125) 6.4 mg/kg once every three weeks or either irinotecan (N=55) 150 mg/m² biweekly or paclitaxel (N=7) 80 mg/m² weekly for 3 weeks. The median duration of treatment was 4.6 months (range: 0.7 to 22.3) in the ENHERTU group and 2.8 months (range: 0.5 to 13.1) in the irinotecan/paclitaxel group.

Serious adverse reactions occurred in 44% of patients receiving ENHERTU 6.4 mg/kg. Serious adverse reactions in >2% of patients who received ENHERTU were decreased appetite, ILD, anemia, dehydration, pneumonia, cholestatic jaundice, pyrexia, and tumor hemorrhage. Fatalities due to adverse reactions occurred in 2.4% of patients: disseminated intravascular coagulation, large intestine perforation, and pneumonia occurred in one patient each (0.8%).

ENHERTU was permanently discontinued in 15% of patients, of which ILD accounted for 6%. Dose interruptions due to adverse reactions occurred in 62% of patients treated with ENHERTU. The most frequent adverse reactions (>2%) associated with dose interruption were neutropenia, anemia, decreased appetite, leukopenia, fatigue, thrombocytopenia, ILD, pneumonia, lymphopenia, upper respiratory tract infection, diarrhea, and hypokalemia. Dose reductions occurred in 32% of patients treated with ENHERTU. The most frequent adverse reactions (>2%) associated with dose reduction were neutropenia, decreased appetite, fatigue, nausea, and febrile neutropenia.

The most common (≥20%) adverse reactions, including laboratory abnormalities, were hemoglobin decreased (75%), white blood cell count decreased (74%), neutrophil count decreased (72%), lymphocyte count decreased (70%), platelet count decreased (68%), nausea (63%), decreased appetite (60%), anemia (58%), aspartate aminotransferase increased (58%), fatigue (55%), blood alkaline phosphatase increased (54%), alanine aminotransferase increased (47%), diarrhea (32%), hypokalemia (30%), vomiting (26%), constipation (24%), blood bilirubin increased (24%), pyrexia (24%), and alopecia (22%).

Use in Specific Populations

• Pregnancy: ENHERTU can cause fetal harm when administered to a pregnant woman. Advise patients of the potential risks to a fetus. There are clinical considerations if ENHERTU is used in pregnant women, or if a patient becomes pregnant within 7 months following the last dose of ENHERTU.
• Lactation: There are no data regarding the presence of ENHERTU in human milk, the effects on the breastfed child, or the effects on milk production. Because of the potential for serious adverse reactions in a breastfed child, advise women not to breastfeed during treatment with ENHERTU and for 7 months after the last dose.
• Females and Males of Reproductive Potential: Pregnancy testing: Verify pregnancy status of females of reproductive potential prior to initiation of ENHERTU. Contraception: Females: ENHERTU can cause fetal harm when administered to a pregnant woman. Advise females of reproductive potential to use effective contraception during treatment with ENHERTU and for at least 7 months following the last dose. Males: Advise male patients with female partners of reproductive potential to use effective contraception during treatment with ENHERTU and for at least 4 months following the last dose. Infertility: ENHERTU may impair male reproductive function and fertility.
• Pediatric Use: Safety and effectiveness of ENHERTU have not been established in pediatric patients.
• Geriatric Use: Of the 234 patients with HER2-positive breast cancer treated with ENHERTU 5.4 mg/kg, 26% were ≥65 years and 5% were ≥75 years. No overall differences in efficacy were observed between patients ≥65 years of age compared to younger patients. There was a higher incidence of Grade 3-4 adverse reactions observed in patients aged ≥65 years (53%) as compared to younger patients (42%). Of the 125 patients with locally advanced or metastatic HER2‑positive gastric or GEJ adenocarcinoma treated with ENHERTU 6.4 mg/kg in DESTINY-Gastric01, 56% were ≥65 years and 14% were ≥75 years. No overall differences in efficacy or safety were observed between patients ≥65 years of age compared to younger patients.
• Hepatic Impairment: In patients with moderate hepatic impairment, due to potentially increased exposure, closely monitor for increased toxicities related to the topoisomerase inhibitor.

To report SUSPECTED ADVERSE REACTIONS, contact Daiichi Sankyo, Inc. at 1-877-437-7763 or FDA at 1-800-FDA-1088 or fda.gov/medwatch.

Please see accompanying full Prescribing Information, including Boxed WARNINGS, and Medication Guide.

DESTINY-Breast03
DESTINY-Breast03 is a global head-to-head, randomized, open-label, registrational Phase III trial evaluating the safety and efficacy of ENHERTU (5.4mg/kg) versus T-DM1 in patients with HER2-positive unresectable and/or metastatic breast cancer previously treated with trastuzumab and a taxane.

The primary efficacy endpoint of DESTINY-Breast03 is PFS based on blinded independent central review. Secondary efficacy endpoints include overall survival, objective response rate, duration of response, clinical benefit rate, PFS based on investigator assessment and safety.

DESTINY-Breast03 enrolled approximately 500 patients at multiple sites in Asia, Europe, North America, Oceania and South America. For more information about the trial, visit ClinicalTrials.gov.

HER2-positive breast cancer
Breast cancer remains the most common cancer and is one of the leading causes of cancer-related deaths in women worldwide.⁶ More than two million cases of breast cancer were diagnosed in 2020, resulting in nearly 685,000 deaths globally.⁶ Approximately one in five cases of breast cancer are considered HER2-positive.⁷

HER2 is a tyrosine kinase receptor growth-promoting protein expressed on the surface of many types of tumors including breast, gastric, lung and colorectal cancers.⁸ HER2 protein overexpression may occur as a result of HER2 gene amplification and is often associated with aggressive disease and poor prognosis in breast cancer.⁹

Despite initial treatment with trastuzumab and a taxane, patients with HER2-positive metastatic breast cancer will often experience disease progression.¹ Additionally, it is estimated that 30 to 50% of patients will develop brain metastases, and while increased availability of HER2 therapies has improved systemic disease control, prognosis following development of brain metastases remains poor.^1-5 More treatment options are needed to further delay progression and extend survival.^1-4

ENHERTU
ENHERTU (fam-trastuzumab deruxtecan-nxki) is a HER2-directed ADC. Designed using Daiichi Sankyo’s proprietary DXd ADC technology, ENHERTU is the lead ADC in the oncology portfolio of Daiichi Sankyo and the most advanced program in AstraZeneca’s ADC scientific platform. ENHERTU consists of a HER2 monoclonal antibody attached to a topoisomerase I inhibitor payload, an exatecan derivative, via a stable tetrapeptide-based cleavable linker.

ENHERTU (5.4mg/kg) is approved in Canada, the EU, Israel, Japan, the UK and the US for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting based on the results from the DESTINY-Breast01 trial.

ENHERTU (6.4mg/kg) is also approved in Israel, Japan and the US for the treatment of adult patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma who have received a prior trastuzumab-based regimen based on the results from the DESTINY-Gastric01 trial.

ENHERTU development program
A comprehensive development program is underway globally, evaluating the efficacy and safety of ENHERTU monotherapy across multiple HER2-targetable cancers, including breast, gastric, lung and colorectal cancers. Trials in combination with other anticancer treatments, such as immunotherapy, are also underway.

ENHERTU was highlighted in the Clinical Cancer Advances 2021 report as one of two significant advancements in the “ASCO Clinical Advance of the Year: Molecular Profiling Driving Progress in GI Cancers,” based on data from both the DESTINY-CRC01 and DESTINY-Gastric01 trials, as well as one of the targeted therapy advances of the year in non-small cell lung cancer (NSCLC), based on the interim results of the HER2-mutated cohort of the DESTINY-Lung01 trial.

ENHERTU received its fourth BTD in the U.S., which was for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received one or more prior anti-HER2-based regimens.

A Type II Variation is currently under review by the European Medicines Agency (EMA) for the treatment of adult patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma who have received a prior anti-HER2-based regimen.

Daiichi Sankyo collaboration
Daiichi Sankyo and AstraZeneca entered into a global collaboration to jointly develop and commercialize ENHERTU (a HER2-directed ADC) in March 2019, and datopotamab deruxtecan (DS-1062; a TROP2-directed ADC) in July 2020, except in Japan where Daiichi Sankyo maintains exclusive rights. Daiichi Sankyo is responsible for manufacturing and supply of ENHERTU and datopotamab deruxtecan.

AstraZeneca in breast cancer
Driven by a growing understanding of breast cancer biology, AstraZeneca is starting to challenge, and redefine, the current clinical paradigm for how breast cancer is classified and treated to deliver even more effective treatments to patients in need – with the bold ambition to one day eliminate breast cancer as a cause of death.

AstraZeneca has a comprehensive portfolio of approved and promising compounds in development that leverage different mechanisms of action to address the biologically diverse breast cancer tumor environment.

AstraZeneca aims to continue to transform outcomes for HR-positive breast cancer with foundational medicines FASLODEX and ZOLADEX and the next-generation oral SERD and potential new medicine camizestrant.

PARP inhibitor LYNPARZA is a targeted treatment option for metastatic breast cancer patients with an inherited BRCA mutation. AstraZeneca with Merck continue to research LYNPARZA in metastatic breast cancer patients with an inherited BRCA mutation and are exploring new opportunities to treat these patients earlier in their disease.

Building on the first approval of ENHERTU, a HER2-directed ADC, in previously treated HER2-positive metastatic breast cancer, AstraZeneca and Daiichi Sankyo are exploring its potential in earlier lines of treatment and in new breast cancer settings.

To bring much needed treatment options to patients with triple-negative breast cancer, an aggressive form of breast cancer, AstraZeneca is testing immunotherapy IMFINZI in combination with other oncology medicines, including LYNPARZA and ENHERTU, evaluating the potential of AKT kinase inhibitor, capivasertib, in combination with chemotherapy, and collaborating with Daiichi Sankyo to explore the potential of TROP2-directed ADC, datopotamab deruxtecan.

AstraZeneca in oncology
AstraZeneca is leading a revolution in oncology with the ambition to provide cures for cancer in every form, following the science to understand cancer and all its complexities to discover, develop and deliver life-changing medicines to patients.

The Company's focus is on some of the most challenging cancers. It is through persistent innovation that AstraZeneca has built one of the most diverse portfolios and pipelines in the industry, with the potential to catalyze changes in the practice of medicine and transform the patient experience.

AstraZeneca has the vision to redefine cancer care and, one day, eliminate cancer as a cause of death.

About AstraZeneca
AstraZeneca is a global, science-led biopharmaceutical company that focuses on the discovery, development and commercialization of prescription medicines in Oncology, Rare Diseases and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca operates in over 100 countries, and its innovative medicines are used by millions of patients worldwide. For more information, please visit www.astrazeneca-us.com and follow us on Twitter @AstraZenecaUS.

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FAQ

What are the latest results for AZN's ENHERTU from DESTINY-Breast03?

The latest results indicate that ENHERTU has a higher progression-free survival and objective response rate compared to T-DM1 in HER2-positive breast cancer.

What was the objective response rate for ENHERTU in the DESTINY-Breast03 trial?

The confirmed objective response rate for ENHERTU was 67.4%, significantly higher than the 20.5% seen with T-DM1.

How does ENHERTU perform in patients with stable brain metastases?

In patients with stable brain metastases, ENHERTU achieved a median progression-free survival of 15 months compared to just 3 months for T-DM1.

Was there any adverse reaction reported for ENHERTU?

Yes, 10.5% of patients treated with ENHERTU experienced interstitial lung disease.

What impact might the new data from DESTINY-Breast03 have on AZN's stock?

Positive clinical results could enhance investor confidence in AZN, potentially impacting its stock performance positively.