This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Phase III to Evaluate Patient´s Preference of Subcutaneous Trastuzumab vs Intravenous in HER2+ Advanced Breast Cancer (NCT01875367), a randomized phase 3 study. The primary outcome is Percentage of Participants With Subcutaneous vs. Intravenous Treatment Preference.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01875367 |
| Phase | Phase 3 |
| Condition | Breast Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 166 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Spanish Breast Cancer Research Group |
| Results posted | Yes |
2. Clinical Question
Population
Patients had HER2-positive advanced breast cancer and had received intravenous trastuzumab for at least 4 months without disease progression. The record describes the population as having disseminated breast cancer. It reports enrollment of 166 participants.
Intervention
Participants received trastuzumab by subcutaneous administration, using either a vial or a single injection device. The study evaluated patient preference after exposure to the intravenous and subcutaneous approaches.
Comparator
The principal preference question contrasted subcutaneous with intravenous trastuzumab. The study also included a comparison of preference between the subcutaneous vial and device approaches. Both arms began with intravenous administration and then received both subcutaneous formulations in a different order.
Primary question
Up to 12 weeks, which method of trastuzumab administration did participants prefer: subcutaneous, intravenous, or no preference? The registry describes the question as a patient-reported preference assessed with questionnaire C2, question number 39.
This is a question about reported experience and preference, not a comparison of tumor response, survival, or disease progression. The preference question offers three possible answers, so its result is naturally categorical. A complete account would describe how many participants selected each answer and the uncertainty around those proportions, as well as how the analysis handled participants without a recorded answer. Those preference results and details are not reported in the registry record.
3. Trial Design
The study is described as a prospective, open, randomized, multicenter, national Phase III trial. Its allocation was randomized, masking was none, and its model was parallel. The registry reports enrollment of 166 participants and a completed status. The start date was 2013-09-18 and the primary completion date was 2016-11-30.
Participants were randomized 1:1 to two sequences. Arm A received one cycle of intravenous trastuzumab, followed by two cycles of subcutaneous trastuzumab using a vial and then two cycles using a single injection device. Arm B also began with one intravenous cycle, but received the two subcutaneous-device cycles before the two subcutaneous-vial cycles. Each arm therefore followed a different order of subcutaneous formulations after the initial intravenous cycle.
Because the study was open, participants and medical staff were not masked to the administration method. That is relevant to a preference outcome: participants were asked directly which method they preferred, and their experience and expectations could inform their answers. Random assignment to sequence can help balance characteristics between the two sequence groups, but it does not make a subjective preference measure equivalent to a blinded clinical outcome.
The listed secondary outcomes include preference between the subcutaneous vial and device, medical-staff preferences, time in the healthcare unit and sitting in a chair or bed, and adverse events. The registry record does not report the statistical plan, the sample-size justification, interim analyses, or the results for these preference and time outcomes.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: This is not a cross-over study.
Overall Study
| Stage | Arm A: T-IV + T-SC Vial + T-SC Device | Arm B: T-IV + T-SC Device + T-SC Vial |
|---|---|---|
| STARTED | 81 | 85 |
| COMPLETED | 76 | 83 |
| NOT COMPLETED | 5 | 2 |
Reasons for not completing this period:
| Reason | Arm A: T-IV + T-SC Vial + T-SC Device | Arm B: T-IV + T-SC Device + T-SC Vial |
|---|---|---|
| Not complete at least 2 questionaries | 4 | 2 |
| Not receive study treatment | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Patients were randomized 1:1 in 2 arms: Arm A: (1 cycle IV-t followed by 2 cycles SC-t with vial followed by 2 cycles SC-t with SID) Arm B: (1 cycle IV-t followed by 2 cycles SC-t with SID followed by 2 cycles SC-t with vial)
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Arm A: T-IV + T-SC Vial + T-SC Device | Arm B: T-IV + T-SC Device + T-SC Vial | Total |
|---|---|---|---|---|
| Participants analysed | 81 | 85 | 166 | |
| Age, Continuous | years | 63 (35 to 93) | 58 (38 to 85) | 60 (35 to 93) |
| Sex: Female, Male: Female | Participants | 81 | 85 | 166 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Race/Ethnicity, Customized: Caucasian | Participants | 78 | 83 | 161 |
| Race/Ethnicity, Customized: Black | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Hispanic | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Arabian | Participants | 1 | 2 | 3 |
| Menopausal status: Premenopausal | Participants | 8 | 12 | 20 |
| Menopausal status: Postmenopausal | Participants | 73 | 73 | 146 |
| Eastern Cooperative Oncology Group (ECOG) performance status: ECOG 0 | Participants | 63 | 61 | 124 |
| Eastern Cooperative Oncology Group (ECOG) performance status: ECOG 1 | Participants | 17 | 24 | 41 |
| Eastern Cooperative Oncology Group (ECOG) performance status: ECOG 2 | Participants | 1 | 0 | 1 |
| Estrogen Receptor: Positive | Participants | 46 | 60 | 106 |
| Estrogen Receptor: Negative | Participants | 35 | 25 | 60 |
| Progesterone Receptor: Negative | Participants | 50 | 38 | 88 |
| Progesterone Receptor: Positive | Participants | 31 | 47 | 78 |
| Time with IV trastuzumab for metastasis at registration | years | 1.9 (0.35 to 13.67) | 1.78 (0.34 to 14.05) | 1.8 (0.34 to 14.05) |
| Treatment/s combined with IV-trastuzumab at registration: Homonotherapy (HT) | Participants | 34 | 36 | 70 |
| Treatment/s combined with IV-trastuzumab at registration: Chemotherapy (CT) | Participants | 12 | 9 | 21 |
| Treatment/s combined with IV-trastuzumab at registration: Other anti-cancer therapy | Participants | 7 | 10 | 17 |
| Treatment/s combined with IV-trastuzumab at registration: Other anti-cancer therapy+CT | Participants | 2 | 4 | 6 |
| Treatment/s combined with IV-trastuzumab at registration: Other anti-cancer therapy+HT | Participants | 2 | 2 | 4 |
| Treatment/s combined with IV-trastuzumab at registration: None | Participants | 24 | 24 | 48 |
| Other anti Human Epidermal growth factor Receptor 2 (HER-2) therapy at registration: Pertuzumab | Participants | 8 | 11 | 19 |
| Other anti Human Epidermal growth factor Receptor 2 (HER-2) therapy at registration: Lapatinib | Participants | 3 | 5 | 8 |
| Other anti Human Epidermal growth factor Receptor 2 (HER-2) therapy at registration: None | Participants | 70 | 69 | 139 |
| Administration route at registration: Intravenous | Participants | 25 | 27 | 52 |
| Administration route at registration: Intramuscular | Participants | 5 | 5 | 10 |
| Administration route at registration: Subcutaneous | Participants | 4 | 5 | 9 |
| Administration route at registration: Oral | Participants | 25 | 29 | 54 |
| Administration route at registration: None | Participants | 22 | 19 | 41 |
| Metastases 1 at diagnosis: No | Participants | 53 | 52 | 105 |
| Metastases 1 at diagnosis: Yes | Participants | 28 | 33 | 61 |
| Visceral metastases at registration: Yes | Participants | 41 | 49 | 90 |
| Visceral metastases at registration: No | Participants | 40 | 36 | 76 |
| Bone metastases at registration: Yes | Participants | 34 | 41 | 75 |
| Bone metastases at registration: No | Participants | 47 | 44 | 91 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants With Subcutaneous vs. Intravenous Treatment Preference, measured over Up to 12 weeks.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants reporting a preference for subcutaneous or intravenous trastuzumab, with “no preference” also available as an answer. The registry says this was assessed up to 12 weeks using questionnaire C2, question number 39, which asks which administration method the participant prefers, all things considered.
Preference is used to capture an aspect of treatment experience that a clinical measure such as tumor response would not describe. It can reflect participants’ overall evaluation of the administration approaches they encountered. In this study, the sequence design exposed participants to intravenous administration and to subcutaneous treatment using both a vial and a device, allowing preference to be asked after experience with these approaches.
Because the question permits three answers, reducing it to a single binary contrast would omit information unless a specific grouping rule were defined. The registry record does not report such a rule or the participant counts for the answer categories. It also does not report how incomplete questionnaires were handled. Therefore the endpoint’s definition is available, but the distribution of responses and its statistical precision cannot be evaluated from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary question and its measurement instrument, but does not report the numbers of participants preferring subcutaneous administration, preferring intravenous administration, or reporting no preference. It also does not report an estimate of the preference distribution, a confidence interval, or a statistical test. Consequently, the direction and precision of the primary preference result cannot be described from the record.
The listed study enrollment is 166. That number describes enrollment, not necessarily the number of participants who answered the primary questionnaire or entered a particular analysis. The number included in the primary endpoint analysis, and the number with missing or incomplete responses, are not reported in the registry record. Enrollment alone cannot establish the denominator used for a preference percentage.
The posted adverse-event information gives counts by randomized arm. For serious adverse events, the registry lists 2 affected participants among 81 at risk in Arm A and 10 among 85 at risk in Arm B. For other adverse events, it lists 76 among 81 in Arm A and 84 among 85 in Arm B. The listed deaths are 0 in each arm. These are descriptive counts; the record does not report a statistical comparison of adverse events or enough detail to interpret these figures as a treatment-effect estimate.
Several serious-event terms are listed with a reported percentage of 1.2% each: fever, hematuria, heart failure, nodule in left breast, cold, and nodule in right breast. The registry does not provide further context in this record about the event-term coding, timing, duration, severity beyond the serious-event designation, or attribution. The reported percentages should therefore be read as registry entries, not as a complete account of all safety considerations.
There is no posted primary analysis from which to assess statistical uncertainty, and no reported analysis plan with which to evaluate how results were selected or adjusted. The study design indicates randomized assignment to sequence, while the preference outcome is self-reported in an open study. Those design features inform how a result could be interpreted, but do not substitute for the missing endpoint results. No conclusion about which administration method participants preferred can be drawn from the registry record alone.
9. Statistical Methods Explained
What does a categorical preference outcome mean?
General statistical explanation: an outcome is categorical when each response belongs to a defined group rather than being a measurement on a continuous scale. The primary question offers subcutaneous, intravenous, and no preference as response categories. A direct description would report the count and proportion in each category, with a stated denominator. Keeping all categories visible avoids concealing the no-preference responses or imposing an unreported grouping rule.
The record identifies a percentage endpoint, but does not report the category counts or the analysis population. A percentage needs a denominator: for example, it matters whether the denominator includes all randomized participants, only participants who completed the questionnaire, or another defined group. The registry record does not state which denominator was used. This prevents reconstruction of the primary result from the enrollment figure.
How does randomization inform interpretation?
General statistical explanation: randomization assigns treatment sequence using a chance-based procedure. It is intended to reduce systematic differences between groups at assignment, so a comparison by assigned group can be less confounded by baseline characteristics than a nonrandomized comparison. Here, assignment was randomized 1:1 to the two administration sequences. The record does not describe the randomization method, any stratification factors, or whether the analysis followed assigned sequence.
The arms differ in the order of the subcutaneous vial and device after an intravenous cycle. Thus, a preference result could reflect participants’ experiences across methods and sequence, rather than a simple comparison of two independent groups exposed to only one administration route. The registry describes a parallel model, but it does not report the statistical method used to account for the sequence or the repeated experiences within a participant. No particular model can be inferred from the listed design alone.
What does a confidence interval communicate?
General statistical explanation: a confidence interval expresses statistical uncertainty around an estimated quantity under the assumptions of the analysis. A narrower interval indicates greater precision for that estimate, while a wider interval indicates less precision. For a categorical preference outcome, intervals could be reported for category proportions or for a defined contrast, if the contrast and method were specified. A confidence interval is not a guarantee that the true value lies within its endpoints, and its interpretation depends on the design and analysis assumptions.
No confidence intervals for the primary preference outcome are reported in the registry record. It is therefore not possible to assess the precision of any preference estimate. A p-value, if reported, would address compatibility with a statistical null model under specified assumptions; it would not by itself describe the size or practical meaning of a preference difference. No primary p-value is reported.
Why can analysis choices matter?
General statistical explanation: a statistical analysis plan specifies which outcomes and comparisons will be analyzed, how participants will be handled, and what methods will be used. Prespecification can limit the risk of choosing an analysis after seeing the results. For this trial, the statistical plan, test or model for the primary endpoint, and approach to confidence intervals are not reported in the registry record. The registry also does not report interim analyses or a sample-size justification.
Planning calculations answer a different question from outcome analyses. They describe assumptions about the amount of information a future study might need for a chosen target, whereas observed results describe data collected in the trial. The stated planning assumptions refer to a two-sided significance level of 0.05, equal allocation, a normal approximation, and effects expressed as fractions of an observed effect. Those assumptions alone do not provide a planning result, and the primary preference effect is not reported. Any planning illustration is not observed power and should not be confused with the number of participants analyzed or the evidence in the trial.
Why can event counts vary more than a simple model expects?
General statistical explanation: over-dispersion occurs when observed variability is greater than a statistical model assumes. If a model underestimates variability, its uncertainty estimates can be too small and its tests can be too optimistic. This issue is particularly relevant to count outcomes when events are unevenly distributed across participants. The registry’s primary endpoint is categorical preference, not a count of repeated events, and no model or over-dispersion assessment is reported. The concept is useful generally, but there is no basis to claim it affected this trial’s reported analyses.
The registry lists participant counts for adverse events, but does not report inferential comparisons, adjusted estimates, or an analysis model for those outcomes. Descriptive counts can show what was recorded in each arm, but they do not establish a statistically tested difference. Without an analysis plan and further outcome detail, the event counts should not be interpreted as a modeled estimate of comparative risk.
10. Multiplicity, Missing Data and Analysis Populations
The trial lists several outcomes in addition to the primary preference question, including subcutaneous vial-versus-device preference, medical-staff preferences, time in the healthcare unit and sitting in a chair or bed, and adverse events. When a study examines multiple outcomes or comparisons, the chance of at least one apparently notable result can increase if each is tested without accounting for the broader set of tests. General statistical approaches to this issue include prespecifying a primary comparison, adjusting inference, or clearly labeling secondary analyses as exploratory. The registry record does not report whether any multiplicity strategy was planned or used.
The registry record also does not report missing-data counts or methods for handling missing questionnaire answers, withdrawals, or other incomplete outcome information. For a preference endpoint, missing responses matter because the analyzed participants may differ from those who did not respond. Without the number and disposition of missing answers, it is not possible to determine how representative the recorded preferences are of all randomized participants.
The analysis populations are not reported. The record does not specify whether the primary analysis used all randomized participants, participants who completed the treatment sequence, or another group. It also does not say whether participants were analyzed according to randomized sequence. These are important distinctions for interpreting a randomized study, especially when the endpoint depends on questionnaire completion after exposure to several administration methods.
The registry reports no statistical analyses for the posted outcomes. Details of the multiplicity approach, missing-data procedures, and analysis populations are therefore not available in this record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Arm A: T-IV + T-SC Vial + T-SC Device | 2 | 81 | 2.5% |
| Arm B: T-IV + T-SC Device + T-SC Vial | 10 | 85 | 11.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Arm A: T-IV + T-SC Vial + T-SC Device | 0 of 81 |
| Arm B: T-IV + T-SC Device + T-SC Vial | 0 of 85 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Arm A: T-IV + T-SC Vial + T-SC Device | 76 of 81 |
| Arm B: T-IV + T-SC Device + T-SC Vial | 84 of 85 |
Most frequent serious adverse event terms
| Event term | Organ system | Arm A: T-IV + T-SC Vial + T-SC Device | Arm B: T-IV + T-SC Device + T-SC Vial |
|---|---|---|---|
| Fever | General disorders | 1 of 81 | 0 of 85 |
| Heart failure | Cardiac disorders | 0 of 81 | 1 of 85 |
| Hematuria | Renal and urinary disorders | 1 of 81 | 0 of 85 |
| Nodule in left breast | Reproductive system and breast disorders | 0 of 81 | 1 of 85 |
| Cold | Infections and infestations | 0 of 81 | 1 of 85 |
| Nodule in right breast | Reproductive system and breast disorders | 0 of 81 | 1 of 85 |
| Lack of strength in left leg | Musculoskeletal and connective tissue disorders | 0 of 81 | 1 of 85 |
| Catheter related infection (Bacteriemia) | Infections and infestations | 0 of 81 | 1 of 85 |
| Stroke | Nervous system disorders | 0 of 81 | 1 of 85 |
| Surgery for surgical castration | Reproductive system and breast disorders | 0 of 81 | 1 of 85 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Arm A: T-IV + T-SC Vial + T-SC Device | Arm B: T-IV + T-SC Device + T-SC Vial |
|---|---|---|---|
| Anemia | Blood and lymphatic system disorders | 27 of 81 | 32 of 85 |
| Aspartate aminotransferase increased | Investigations | 15 of 81 | 17 of 85 |
| White blood cells decreased | Investigations | 15 of 81 | 17 of 85 |
| Creatinine increased | Investigations | 13 of 81 | 17 of 85 |
| Alkaline phosphatase increased | Investigations | 12 of 81 | 15 of 85 |
| Alanine aminotransferase increased | Investigations | 16 of 81 | 10 of 85 |
| Fatigue | General disorders | 10 of 81 | 16 of 85 |
| Neutrophil count decreased | Investigations | 13 of 81 | 13 of 85 |
| Injection site reaction | General disorders | 9 of 81 | 6 of 85 |
| Platelet count decreased | Investigations | 4 of 81 | 8 of 85 |
Serious events with the highest arm-level rate: fever (1.2%), hematuria (1.2%), heart failure (1.2%), nodule in left breast (1.2%), cold (1.2%).
The registry lists serious adverse events by randomized arm. Arm A has 2 affected participants among 81 at risk, and Arm B has 10 affected participants among 85 at risk. For other adverse events, it lists 76 affected participants among 81 at risk in Arm A and 84 among 85 at risk in Arm B. Deaths are listed as 0 in each arm. These are counts of participants with an event, not a comparative statistical analysis.
The serious-event terms shown in the record are fever, hematuria, heart failure, nodule in left breast, cold, and nodule in right breast, each reported as 1.2%. The record does not explain the event-term coding or provide additional context about timing, duration, severity beyond serious-event status, or attribution. The listed counts and percentages should be read as the registry’s descriptive safety information, not as proof of a causal relationship or a complete evaluation of comparative safety.
No inferential comparison or uncertainty interval for these safety figures is reported. Differences in the displayed counts cannot be interpreted as statistically established differences from the registry information alone.
12. What the Result Does, and Does Not, Mean
The study addresses a patient-centered question: which route of trastuzumab administration participants preferred after receiving intravenous treatment and experiencing subcutaneous treatment in two forms. The randomized sequence design and direct questionnaire provide a framework for evaluating reported preference. The registry record does not, however, report the primary response counts or a statistical analysis. It therefore does not establish the distribution of preferences or its precision.
A preference result, if available, would answer a question about participants’ reported experience under the study conditions. It would not by itself establish that one administration approach produces better cancer outcomes, is safer, or is appropriate for a particular person. The listed primary endpoint is preference, and the registry record does not report tumor response or survival results as primary outcomes.
The adverse-event counts provide descriptive information for the two randomized sequences. The record does not report an adjusted comparison, uncertainty estimates, or details that would support a causal interpretation of the counts. The study’s open design is also relevant to a subjective outcome: participants knew the administration method, and expectations could form part of the experience they reported. Randomization to sequence does not remove that limitation.
The record supports a description of the trial’s question, sequence design, and selected adverse-event counts. It does not support a conclusion about which method was preferred, how certain that conclusion would be, or whether any preference difference was statistically significant. Those conclusions require the missing primary endpoint results and analysis details.
13. Why This Trial Matters Statistically
Preference studies address a dimension of treatment experience that clinical outcomes alone do not capture. Asking participants to compare methods they have experienced can inform understanding of how administration format is perceived. In this trial, participants were assigned to different sequences of intravenous treatment and subcutaneous treatment using a vial and a single injection device. That design makes the order of exposure relevant to how the preference question should be interpreted.
Statistically, the study illustrates the importance of matching the analysis to the endpoint and design. The primary outcome has three response categories, while the trial assigns participants to two sequences. A useful interpretation would need to make the response categories, analysis denominator, treatment of missing answers, and comparison strategy clear. Those details are not reported in the registry record, and the primary response counts are also absent.
The open design is another important consideration. Preference is inherently reported by participants, and awareness of the administration method is part of the context in which that preference is formed. Randomization can support fair comparison of assigned sequences, but it cannot mask the experience or remove expectations from a subjective response.
The record also demonstrates why descriptive safety counts and an outcome analysis should not be conflated. Counts by arm are useful information, but inferential claims require a specified comparison and assessment of uncertainty. The registry describes the study question and gives some safety data, yet leaves the primary statistical evidence unavailable. That gap limits what can be learned about the stated preference objective from this record.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The central limitation is that the primary preference outcome is not reported numerically. Although the registry identifies the question, its response options, and a timeframe of up to 12 weeks, it does not give the number or percentage choosing each option. Without those data, neither the direction of preference nor its precision can be assessed.
The primary analysis denominator, missing questionnaire responses, and analysis population are also not reported. This makes it impossible to determine how the enrolled participants relate to the participants contributing to the endpoint. The registry does not state how incomplete responses were handled or whether participants were analyzed according to randomized sequence.
The record does not report a statistical analysis plan, primary test or model, confidence intervals, interim analyses, or sample-size justification. It lists several secondary outcomes but does not describe a multiplicity strategy. As a result, the planned inferential framework and the status of secondary findings cannot be evaluated.
The open design is particularly relevant to patient preference because participants knew which administration method they received. The assigned sequences also differ in the order of subcutaneous vial and device exposure; the record does not report how sequence or order was incorporated into the primary analysis. The adverse-event information is limited to counts and selected terms, without further context or comparative statistical estimates. These limitations concern the registry information available, and should not be mistaken for evidence that unreported analyses were or were not performed.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Phase III to Evaluate Patient´s Preference of Subcutaneous Trastuzumab vs Intravenous in HER2+ Advanced Breast Cancer — NCT01875367.
- Registry record last updated 2023-04-05; status last verified 2023-04.
- Results first posted 2021-02-01.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT01875367 is a completed randomized Phase III trial of preference for intravenous or subcutaneous trastuzumab in HER2-positive advanced breast cancer. The record describes 166 enrolled participants and two sequences: an intravenous cycle followed by subcutaneous vial and device cycles in one order, or the same approaches in the reverse order.
The primary endpoint asked participants to choose subcutaneous, intravenous, or no preference using questionnaire C2, question number 39, up to 12 weeks. The preference counts and statistical analysis are not reported in the registry record. Descriptive adverse-event counts are listed by arm, including serious events, other events, and deaths. The analysis plan, missing-data methods, and analysis populations are not reported.