A Study to Evaluate Patient Preference for Home Administration of Fixed-Dose Combination of Pertuzumab and Trastuzumab for Subcutaneous Administration in Participants With Early or Locally Advanced/Inflammatory HER2-Positive Breast Cancer

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation of P+H IV and/or administration of PH FDC SC completed the following question of the HCPQ: Q1a: "Please indicate which treatment preparation the estimates relate to". HCPs were required to select one of the following options: PH FDC SC or P+H IV. The response to Q1a was used to further assess Q1b: How long did it take to prepare the treatment for use? Percentages were rounded off.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation of P+H IV and/or administration of PH FDC SC completed the following question of the HCPQ: Q1b: "How long did it take to prepare the treatment for use?" This was a follow up question to Q1a: "Please indicate which treatment preparation the estimates relate to" for which HCPs were required to select one of the following options: PH FDC SC or P+H IV.

HCP=any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation of P+H IV and/or administration of PH FDC SC completed the following question 2 of the HCPQs: In your opinion, if all P+H IV infusions were switched to PH FDC SC injections, please indicate how strongly you agree/disagree with each of the following statements. 2a: Staff will have increased availability for other tasks in the pharmacy. 2b: Administrative procedures related to PH FDC SC require less time. 2c: Using PH FDC SC provides more flexibility for pharmacy staff in managing their workload. 2d: As PH FDC SC is fixed-dose, potential dosing errors are avoided. 2e: As PH FDC SC is fixed-dose, there is less drug wastage. 2f: Less storage space for PH FDC SC-related supplies is required in the pharmacy, as there is no need for reconstitution. 2g: Number of preparation steps \& staff time commitment are reduced. Percentages were rounded off.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with administration of P+H IV and/or PH FDC SC completed the following Questions of the HCPQ: Q1a: Please indicate which treatment preparation the estimates relate to. Q1b: Did the participant have existing IV access? Q1c: If new IV access was needed for this cycle of treatment, please indicate what type of IV access was provided. Q1d: What type of existing IV access did the participant have? Q1e: When did the existing IV access place? Percentages were rounded off.

PICC = peripherally inserted central catheter.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with administration of P+H IV and/or PH FDC SC completed the following Questions of the HCPQ: Q1c: If new IV access was needed for this cycle of treatment, how long (in minutes) this took to set up? Q1f: How long (in minutes) did it take to administer the treatment (P+H IV or PH FDC SC)? Q1g: How long (in minutes) was the participant in the Treatment Area in total? Percentages have been rounded off.

HCP was defined as any personnel involved in the drug preparation \&/or drug administration processes. HCPs who have had experience with administration of P+H IV \&/or PH FDC SC completed Q2 (2a-2e) of the HCPQ: In your opinion, if all P+H IV infusions were switched to PH FDC SC injections, please indicate how strongly you agree/disagree with each of the following statements. 2a: Participants may be moved out of the Treatment Area (for infusion treatment) to receive PH FDC SC injections. 2b: PH FDC SC's SC route of administration allows for more flexible treatment scheduling. 2c: Frees up infusion chairs for participants whose treatments can only be given IV. 2d: Waiting list for any P+H IV treatment at the Treatment Area is reduced. 2e: Staff's work burden is reduced, enhancing work performance. The 6 available options were: Strongly Disagree, Disagree, Neutral, Agree, Strongly Agree and Not applicable. Percentages were rounded off.

HCP was defined as any personnel involved in the drug preparation \&/or drug administration processes. HCPs who have had experience with administration of P+H IV \&/or PH FDC SC completed Question 2 (2f to 2j) of the HCPQ: In your opinion, if all P+H IV infusions were switched to PH FDC SC injections, please indicate how strongly you agree/disagree with each of the following statements. 2f: More interaction time between HCPs and participants. 2g: Staff have more time for further professional education/development. 2h: Staff has more time for administrative tasks. 2i: Participants on PH FDC SC spend less time in the Treatment Area. 2j: Participants prefer PH FDC SC to P+H IV. The 6 available options were: Strongly Disagree, Disagree, Neutral, Agree, Strongly Agree and Not applicable. Percentages were rounded off.

HCPs who have had experience with administration of P+H IV \&/or PH FDC SC completed Questions 3 to 11 of the HCPQ: Q3: Which was more convenient for the participant? Q4: Which was better for optimising participant care at your institution? Q5: Which required less time to administer (excluding observation period)? Q6: Which required less use of institutional resources (e.g., staff time, facility costs, equipment use)? Q7: Which required less time to administer all the treatment (including IV chemotherapy)? Q8: Which allowed for attending to more participants because of time savings from the mode of administration of pertuzumab and trastuzumab? Q9: During the NP you had to administer IV chemotherapy through participant's IV access. You prefer to accompany IV chemotherapy with? Q10: Which was preferred by participants? Q11: How frequently would you recommend PH FDC SC administration to your participants in the future? Percentages were rounded off.

pCR was defined as the absence of residual invasive cancer on hematoxylin and eosin evaluation of the complete resected breast specimen and all sampled regional lymph nodes following completion of neoadjuvant systemic therapy (i.e., ypT0/Tis ypN0), according to the current American Joint Committee on Cancer (AJCC) staging system classification. Percentages were rounded off.

EORTC QLQ-C30=cancer-specific instrument consisting of 30 questions that evaluated 5 aspects of participant functioning (physical, emotional, role, cognitive \& social), 3 symptom scales (fatigue, nausea \& vomiting \& pain), global health status/quality of life (GHS/QoL) \& 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea \& financial difficulties). Functioning \& symptom items used a 4-point scale, scores ranging from 1=Not at all to 4=Very much. GHS/QoL questions used a 7-point scale, scores ranging from 1=Very poor to 7=Excellent. All EORTC scales \& single-item measures were linearly transformed to a score range of 0-100. High score for functional/GHS scale=high/healthy level of functioning/better HRQoL \& high score for symptom scale=high level of symptom severity. A positive change from baseline=improvement \& negative change=worsening in QoL \& functioning scales. A positive change from baseline=deterioration \& negative change=improvement in symptom scales.

EORTC QLQ-C30=cancer-specific instrument consisting of 30 questions that evaluated 5 aspects of participant functioning (physical, emotional, role, cognitive \& social), 3 symptom scales (fatigue, nausea \& vomiting \& pain), GHS/QoL \& 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea \& financial difficulties). Functioning \& symptom items used a 4-point scale, scores ranging from 1=Not at all to 4=Very much. GHS/QoL questions used a 7-point scale, scores ranging from 1=Very poor to 7=Excellent. All EORTC scales \& single-item measures were linearly transformed to a score range of 0-100. High score for functional/GHS scale=high/healthy level of functioning/better HRQoL \& high score for symptom scale=high level of symptom severity. A positive change from baseline=improvement \& negative change=worsening in QoL \& functioning scales. A positive change from baseline=deterioration \& negative change=improvement in symptom scales.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation and/or administration of PH FDC SC completed the following questions of the HCPQ: Q1a: Where was the treatment prepared? Q1c: Which healthcare professionals were involved in the treatment preparation processes? The 4 available response options for Q1a were: Participant's home, Hospital pharmacy, Day oncology unit, or Other. The 5 available response options for Q1c were: Physician, Nurse, Pharmacist, All of them or Other. Percentages were rounded off.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation and/or administration of PH FDC SC completed the following parts of question Q1b: Q1b(1): How long did it take to prepare the treatment for use? Q1b(2): Time from the preparation place to reach the participant's home.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with preparation and/or administration of PH FDC SC completed the questions 2, 3 and 4 of the HCPQ: Q2: If all PH FDC SC injections were switched from an in-hospital setting to the participant´s home, please indicate how strongly you agree or disagree with each of the following statements: 2a: Staff will have increased availability for other tasks in the hospital´s pharmacy. 2b: Administrative procedures related to PH FDC SC will require less time. 2c: Number of preparation steps and staff time commitment are reduced. The 5 response options were: Strongly disagree, Disagree, Neutral, Agree, Strongly agree or Not applicable. Q3: Which took less time? Q4: Which required less use of institutional resources? The 4 available options were: Participant's home, In hospital, No difference, or Unsure. Percentages were rounded off.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with the preparation and/or administration of PH FDC SC completed the following questions of the HCPQ: Q1a: How long did it take to travel to the participant's home to administer PH FDC SC? Q1b: How long did it take for the participant to travel to the hospital to receive PH FDC SC? Q1c: How long did it take to administer PH FDC SC? Q1d: How long was the participant treatment time? Q1e: How much time did the participant spend in hospital? Q1f: How much time did you spend at the participant's home? From arrival to departure time.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with the preparation and/or administration of PH FDC SC completed the following questions of the HCPQ: Q1g. Does the participant still have implanted IV access? The 2 available responses were: Yes or No. Q1h: If question 1g was answered 'No', when was the IV access removed? The 3 available responses were: After surgery and before initiating adjuvant treatment; After initiating adjuvant treatment, or Not applicable. Q1i: If question 1g was answered 'Yes', what is the main reason to keep the IV access? The 5 available responses were: Local protocol; Risk of recurrence; Participant preference; Not applicable, or Other. Percentages were rounded off.

HCPs who have had experience with the preparation and/or administration of PH FDC SC completed the following questions of the HCPQ: Q1j: How long do you keep implanted IV access in early human epidermal growth factor receptor 2 (HER2)-positive breast cancer participants with pCR following surgery in your institution? The 5 available responses were: <12 months, ≥12 months, 18 months, <24 months, ≥24 months. Q1k: When is the decision point for you to decide to remove IV access for early HER2+ breast cancer participants? The 6 available responses were: Before surgery, After surgery, After PCR results, After completion of full adjuvant therapy, After completion of IV antineoplastic within adjuvant therapy, and Other. Q1l: Do you consider it necessary to keep implanted IV access knowing that the participant's treatment will be SC until the full 18 cycles? The 3 available responses were: Yes, No, and Unsure. Percentages were rounded off.

HCPs who have had experience with the preparation and/or administration of PH FDC SC completed the following question of the HCPQ: Q2: If all PH FDC SC injections were switched from an in-hospital setting to the participant's home, please indicate how strongly you agree/disagree with each of the following statements: 2a: PH FDC SC's SC route of administration allows for more flexible treatment scheduling. 2b: Frees up infusion chairs or outpatient procedure rooms used to administer SC injections. 2c: Waiting list for infusion chairs or outpatient procedure rooms is reduced. 2d: Staff's work burden is reduced, enhancing work performance. 2e: More interaction time between HCPs and participants on IV treatment. 2f: Staff has more time for administrative tasks. 2g: Participants will spend less time in hospital. 2h: Participants prefer PH FDC SC at home. The 6 available responses were: Strongly disagree, Disagree, Neutral, Agree, Strongly agree, \& Not applicable.

HCP was defined as any personnel involved in the drug preparation and/or drug administration processes. HCPs who have had experience with the preparation and/or administration of PH FDC SC completed the following questions of the HCPQ: Q3: Which was more convenient for the participant? Q4: Which was better for optimising participant care? Q5: Which required less use of institutional resources? Q6: Which was preferred by participants? The 4 responses available were: Participant's home, In hospital, No difference, and Unsure. Q7: How frequently would you recommend PH FDC SC at home to your participants in the future? The 3 responses available were: Always, Sometimes, and Never. Percentages were rounded off.

EORTC QLQ-C30=cancer-specific instrument consisting of 30 questions that evaluated 5 aspects of participant functioning (physical, emotional, role, cognitive \& social), 3 symptom scales (fatigue, nausea \& vomiting \& pain), GHS/QoL \& 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea \& financial difficulties). Functioning \& symptom items used a 4-point scale, scores ranging from 1=Not at all to 4=Very much. GHS/QoL questions used a 7-point scale, scores ranging from 1=Very poor to 7=Excellent. All EORTC scales \& single-item measures were linearly transformed to a score range of 0-100. High score for functional/GHS scale=high/healthy level of functioning/better HRQoL \& high score for symptom scale=high level of symptom severity. A positive change from baseline=improvement \& negative change=worsening in QoL \& functioning scales. A positive change from baseline=deterioration \& negative change=improvement in symptom scales.

The percentage of participants who chose to receive PH FDC SC in the home setting or in the hospital setting during the treatment continuation period is reported.

AE was defined as any untoward medical occurrence in a clinical study participant temporally associated with use of a study treatment, whether or not considered related to the study treatment. SAE=any untoward medical occurrence that, at any dose: Results in death; Is life threatening; Requires inpatient hospitalization/prolongation of existing hospitalization; Results in persistent disability/incapacity \&/or is a congenital anomaly/birth defect. Cardiac AEs=asymptomatic decline in left ventricular ejection fraction (LVEF) of ≥10% from baseline to an LVEF <50%; asymptomatic decline in LVEF requiring treatment/leading to discontinuation of study treatment; congestive heart failure (CHF). AEs ≥Grade 3=marked limitation of physical activity. Comfortable at rest, but any ordinary activity causes fatigue, palpitation/dyspnea; Inability to carry any physical activity without discomfort. Symptoms of cardiac insufficiency at rest. Any physical activity leads to discomfort.

An AE was any untoward medical occurrence in a clinical study participant temporally associated with the use of a study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable \& unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of study intervention. Participants who discontinued the study due to AEs are reported here.

AE was defined as any untoward medical occurrence in a clinical study participant temporally associated with use of a study treatment, whether or not considered related to the study treatment. SAE=any untoward medical occurrence that, at any dose: Results in death; Is life threatening; Requires inpatient hospitalization/prolongation of existing hospitalization; Results in persistent disability/incapacity \&/or is a congenital anomaly/birth defect. Cardiac AEs=asymptomatic decline in LVEF of ≥10% from baseline to an LVEF <50%; asymptomatic decline in LVEF requiring treatment/leading to discontinuation of study treatment; CHF. AEs ≥Grade 3=marked limitation of physical activity. Comfortable at rest, but any ordinary activity causes fatigue, palpitation/dyspnea; Inability to carry any physical activity without discomfort. Symptoms of cardiac insufficiency at rest. Any physical activity leads to discomfort.

An AE was any untoward medical occurrence in a clinical study participant temporally associated with the use of a study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable \& unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of study intervention. Participants who discontinued the study due to AEs are reported here.

AE was defined as any untoward medical occurrence in a clinical study participant temporally associated with use of a study treatment, whether or not considered related to the study treatment. SAE=any untoward medical occurrence that, at any dose: Results in death; Is life threatening; Requires inpatient hospitalization/prolongation of existing hospitalization; Results in persistent disability/incapacity \&/or is a congenital anomaly/birth defect. Cardiac AEs=asymptomatic decline in LVEF of ≥10% from baseline to an LVEF <50%; asymptomatic decline in LVEF requiring treatment/leading to discontinuation of study treatment; CHF. AEs ≥Grade 3=marked limitation of physical activity. Comfortable at rest, but any ordinary activity causes fatigue, palpitation/dyspnea; Inability to carry any physical activity without discomfort. Symptoms of cardiac insufficiency at rest. Any physical activity leads to discomfort.

An AE was any untoward medical occurrence in a clinical study participant temporally associated with the use of a study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable \& unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of study intervention. Participants who discontinue study due to AEs will be reported.