HER2-Positive Breast Carcinoma, Invasive Breast Carcinoma, Metastatic Malignant Neoplasm in the Brain, Recurrent Breast Carcinoma, Stage IV Breast Cancer AJCC v6 and v7
Conditions
Brief summary
This randomized phase II trial studies how well whole-brain radiation therapy or stereotactic radiosurgery with or without lapatinib ditosylate works in treating patients with breast cancer that has too many of a protein called human epidermal growth factor receptor 2 (HER2) on its cells and has spread to the brain. Radiation therapy uses high energy x rays to kill tumor cells and shrink tumors. Stereotactic radiosurgery is a specialized radiation therapy that delivers a single, high dose of radiation directly to the tumor and may kill more tumor cells and cause less damage to normal tissue. Lapatinib ditosylate may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. It is not yet known whether whole-brain radiation therapy or stereotactic radiosurgery together with lapatinib ditosylate is an effective treatment for brain metastasis from breast cancer.
Detailed description
PRIMARY OBJECTIVES: I. To determine if there is a signal for an increase in complete response (CR) rate in the measurable brain metastases at 12 weeks post radiation therapy (RT) (whole brain or stereotactic radiosurgery \[SRS\]) as determined by magnetic-resonance imaging (MRI) scan of the brain, with the addition of lapatinib (lapatinib ditosylate) to whole-brain radiation therapy (WBRT)/SRS compared to WBRT/SRS alone. SECONDARY OBJECTIVES: I. To evaluate CR rate of the measurable brain metastases at 4 weeks post RT (WBRT/SRS) as determined by MRI scan of the brain, with the addition of lapatinib to WBRT/SRS compared to WBRT/SRS alone. II. To evaluate objective response rate of measurable brain metastases at 4 and 12 weeks post RT (WBRT/SRS) as determined by MRI scan of the brain, with the addition of lapatinib to WBRT/SRS compared to WBRT/SRS alone. III. To evaluate targeted lesion-specific objective response rate (CR + partial response \[PR\]) at 4 and 12 weeks post WBRT/SRS. IV. To evaluate central nervous system (CNS) progressive disease outside the targeted measurable disease with addition of lapatinib to WBRT/SRS compared to WBRT/SRS alone. V. To evaluate targeted lesion-specific progression at 4 and 12 weeks post WBRT/SRS. VI. To evaluate treatment related adverse events when adding lapatinib to WBRT/SRS compared to WBRT/SRS alone. VII. To evaluate overall CNS complete response: disappearance of all CNS target lesions sustained for at least 4 weeks; with no new lesions, no use of corticosteroids, and patient is stable or improved clinically, when adding lapatinib to WBRT/SRS compared to WBRT/SRS alone. VIII. To evaluate overall CNS progressive disease (within or outside targeted measurable disease) with addition of lapatinib to WBRT/SRS compared to WBRT/SRS alone. IX. To evaluate overall survival when adding lapatinib to WBRT/SRS compared to WBRT/SRS alone. OUTLINE: Patients are randomized to 1 of 2 treatment arms. ARM A: Patients undergo WBRT 5 days a week for 3 weeks for a total of 15 treatments or SRS for 1 treatment. ARM B: Patients undergo WBRT or SRS as in Arm A. Patients also receive lapatinib ditosylate orally (PO) once daily (QD) for 6 weeks. After completion of study treatment, patients are followed up at 4 and 12 weeks and then every 12 weeks thereafter.
Interventions
OTHERLaboratory Biomarker Analysis
Correlative studies
DRUGLapatinib Ditosylate
Given PO
RADIATIONStereotactic Radiosurgery
Undergo SRS
RADIATIONWhole-Brain Radiotherapy
Undergo WBRT
Sponsors
NRG Oncology
National Cancer Institute (NCI)
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Pathologically (histologically or cytologically) proven diagnosis of invasive breast cancer * HER2-overexpressing breast cancer (3+ staining by immunohistochemistry or HER2 gene amplification by fluorescent in situ hybridization \[FISH\] or silver in situ hybridization \[SISH\] \>= 2.0) * At least 1 measurable unirradiated parenchymal brain metastasis within 21 days prior to study entry; patients who are to undergo SRS must have no more than 10 brain metastases; there is no limit on number of brain metastases for WBRT; the minimum size as measured on T1-weighted gadolinium-enhanced MRI must be as follows according to the number of brain metastases: * For a single solitary lesion the size must be \>= 10 mm * For 2 or more lesions, the size of at least 2 of the lesions must be \>= 5 mm * Patients may also have the following provided the size requirements above are met: * Progressive parenchymal brain metastasis following stereotactic radiosurgery for 1-3 brain metastases, with at least 1 new measurable brain lesion * Progressive parenchymal brain metastasis following surgical resection of 1-3 brain metastases, with at least 1 measurable brain lesion * History/physical examination within 21 days prior to study entry * Karnofsky performance status \>= 60 within 21 days prior to study entry * Able to swallow and retain oral medication (note: for patients unable to swallow tablets, an oral suspension preparation is acceptable) * Absolute neutrophil count (ANC) \>= 1,200 cells/mm\^3 (within 21 days prior to study entry) * Platelets \>= 70,000 cells/mm\^3 (within 21 days prior to study entry) * Hemoglobin \>= 8.0 g/dL (note: the use of transfusion or other intervention to achieve hemoglobin \[Hgb\] \>= 8.0 g/dL is acceptable) (within 21 days prior to study entry) * Creatinine \< 1.5 times institutional upper limit of normal (within 21 days prior to study entry) * Bilirubin \< 1.5 times institutional upper limit of normal (within 21 days prior to study entry) * Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) =\< 3.0 times institutional upper limit of normal with or without liver metastasis (within 21 days prior to study entry) * Patient must provide study specific informed consent prior to study entry * Women of childbearing potential must have a negative serum pregnancy test within 21 days prior to study entry * Sexually active women of childbearing potential and sexually active men must practice adequate contraception during therapy and for 12 months after protocol treatment completion * Prior lapatinib is allowed as long as the last dose received was \> 21 days prior to study entry and provided the patient has not received it at any time after the diagnosis of brain metastasis
Exclusion criteria
* Prior WBRT * Prior radiation therapy (RT) (any site) with concurrent lapatinib defined as 1 or more days on which the patient received both radiation therapy and lapatinib on the same day * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Prior invasive malignancy (except non-melanomatous skin cancer, curatively resected thyroid papillary carcinoma, and invasive and non-invasive cancers related to the breast cancer) unless disease free for a minimum of 3 years * Leptomeningeal disease * Prior radiotherapy to the region of the study cancer that would result in overlap of radiation therapy fields except patients who have progressed following stereotactic radiosurgery for 1-3 brain metastases, with at least one new lesion * Severe, active co-morbidity, defined as follows: * Unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months * Transmural myocardial infarction within the last 6 months * Acute bacterial or fungal infection requiring intravenous antibiotics at the time of study entry * Chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy at the time of study entry * Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects; hepatic or biliary disease that is acute or currently active or that requires antiviral therapy (with the exception of patients with Gilbert's syndrome, asymptomatic gallstones, liver metastases, or stable chronic liver disease per investigator assessment) * History of left ventricular ejection fraction (LVEF) below institutional normal unless repeated and within institutional normal range within 90 days of study entry * Grade 2 or greater rash of any cause at time of study entry * Grade 2 or greater diarrhea of any cause at time of study entry
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Complete Response (CR) Rate in the Brain at 12 Weeks Post-radiation Therapy (RT) Using the RECIST 1.1 Criteria Based on Brain Magnetic Resonance Imaging (MRI) | Baseline and 12 weeks post RT (approximately 12 weeks from start of treatment if SRS and 15 if WBRT) | The Response Evaluation Criteria in Solid Tumors (RECIST) criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI | Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT) | The WHO/modified McDonald Criteria evaluates changes in bidimensional tumor measurements. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients. |
| Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT) | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Objective response is defined as a complete or partial response. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Partial response is defined as ≥ 30% reduction in the sum of diameters of up to 2 of the largest target lesions. Rate is calculated by dividing the number of patients with objective response by the number of analyzable patients. |
| Percentage of Participants With Progression in the Brain Outside the Targeted Measurable Disease Using the RECIST 1.1 Criteria Based on Brain MRI | From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months. | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. CNS progressive disease outside the targeted measureable disease was determined by a retrospective central review of MRI scans by the study neuroradiology co-chair and is defined as the first occurrence since baseline of new lesions or progression of non-target lesions. Time to CNS progressive disease is defined as time from randomization to the date of progressive disease, last known follow-up (censored), or death (competing risk). Progression rates are estimated using the cumulative incidence method. One-year rates are provided. |
| Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT) | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Objective response is defined as a complete or partial response. Complete response is defined as the complete disappearance of all enhancing disease and partial response is defined as ≥ 30% reduction in the diameter of the target lesion. Lesions were evaluated individually. Rate is calculated by dividing the number of lesions with objective response by the number of analyzable lesions. |
| Complete Response Rate in the Brain at 4 Weeks Post-RT Using the RECIST 1.1 Criteria Based on Brain MRI | Baseline and 4 weeks post RT (approximately 4 weeks from start of treatment if SRS and 7 if WBRT) | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients. |
| Frequency of Highest Treatment-related Adverse Event Per Participant | From randomization to last follow-up. Maximum follow-up at time of analysis was 71.6 months. | Adverse events reported as definitely, probably, or possibly related to protocol treatment. Common Terminology Criteria for Adverse Events (version 4.0) grades adverse event severity from 1=mild to 5=death. Summary data provided in this outcome measure. See Adverse Events Module for specific Adverse Event data. |
| Overall Complete Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months. | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Overall complete response is defined as the complete disappearance of all CNS target lesions sustained for at least 4 weeks; with no new lesions, no use of corticosteroids, and patient is stable or improved clinically. All site-reported MRI data and all site-reporting of clinical progressive disease indicators were used in this analysis. Rate is calculated by dividing the number of participants with overall complete response by the number of analyzable participants. |
| Overall Progression Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months. | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Overall progression is defined as unequivocal progression, new or worsening tumor-related neurological symptoms, tumor-related increase in steroid dose, new primary in brain, or progression in target lesions. All site-reported MRI data and all site-reporting of clinical progressive disease indicators were used in this analysis. Rate is calculated by dividing the number of participants with progression by the number of analyzable participants. |
| Overall Survival (OS) | From randomization to last follow-up. Maximum follow-up at time of analysis was 71.6 months. | An event for overall survival is death due to any cause. Survival time is defined as time from randomization to the date of death or last known follow-up (censored). Rates are estimated by the Kaplan-Meier method. Analysis occurred after 101 deaths were reported. |
| Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT) | The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Progression is defined as ≥ 20% increase in the diameter of the target lesion relative to nadir. Lesions were evaluated individually. Rate is calculated by dividing the number of lesions with progression by the number of analyzable lesions. |
Countries
Canada, South Korea, United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Radiation Therapy Stereotactic radiosurgery (SRS) or 3 weeks of whole brain radiotherapy (WBRT) | 65 |
| Lapatinib and Radiation Therapy 1000 mg Lapatinib for six weeks with radiation therapy (stereotactic radiosurgery (SRS) or 3 weeks of whole brain radiotherapy (WBRT)) | 71 |
| Total | 136 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Protocol Violation | 7 | 0 |
Baseline characteristics
| Characteristic | Radiation Therapy | Total | Lapatinib and Radiation Therapy |
|---|---|---|---|
| Age, Customized < 50 years | 22 Participants | 47 Participants | 25 Participants |
| Age, Customized ≥ 50 years | 43 Participants | 89 Participants | 46 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 8 Participants | 11 Participants | 3 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 57 Participants | 124 Participants | 67 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 1 Participants | 1 Participants |
| Graded Prognostic Assessment for Breast Cancer (Breast-GPA) 1.5-2.0 | 5 Participants | 9 Participants | 4 Participants |
| Graded Prognostic Assessment for Breast Cancer (Breast-GPA) 2.5-3.0 | 35 Participants | 72 Participants | 37 Participants |
| Graded Prognostic Assessment for Breast Cancer (Breast-GPA) 3.5-4.0 | 25 Participants | 55 Participants | 30 Participants |
| Karnofsky Performance Status 60 | 9 Participants | 11 Participants | 2 Participants |
| Karnofsky Performance Status 70-80 | 29 Participants | 56 Participants | 27 Participants |
| Karnofsky Performance Status 90-100 | 27 Participants | 69 Participants | 42 Participants |
| Planned RT SRS | 6 Participants | 12 Participants | 6 Participants |
| Planned RT WBRT | 59 Participants | 124 Participants | 65 Participants |
| Previous Stereotactic SRS or Surgery No | 37 Participants | 78 Participants | 41 Participants |
| Previous Stereotactic SRS or Surgery Yes | 5 Participants | 11 Participants | 6 Participants |
| Sex: Female, Male Female | 65 Participants | 136 Participants | 71 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
| Use of Non-central nervous system (CNS) penetrating HER2 Blockade at Study Entry No (None) | 23 Participants | 51 Participants | 28 Participants |
| Use of Non-central nervous system (CNS) penetrating HER2 Blockade at Study Entry Yes (Trastuzumab and/or Pertuzumab) | 42 Participants | 85 Participants | 43 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 48 / 63 | 53 / 71 |
| other Total, other adverse events | 49 / 63 | 63 / 71 |
| serious Total, serious adverse events | 17 / 63 | 16 / 71 |
Outcome results
Primary
Complete Response (CR) Rate in the Brain at 12 Weeks Post-radiation Therapy (RT) Using the RECIST 1.1 Criteria Based on Brain Magnetic Resonance Imaging (MRI)
The Response Evaluation Criteria in Solid Tumors (RECIST) criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients.
Time frame: Baseline and 12 weeks post RT (approximately 12 weeks from start of treatment if SRS and 15 if WBRT)
Population: Evaluable data for determining the 12-week post-RT RECIST response was available for 52 eligible participants on the RT alone arm and 64 on the lapatinib arm.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Radiation Therapy | Complete Response (CR) Rate in the Brain at 12 Weeks Post-radiation Therapy (RT) Using the RECIST 1.1 Criteria Based on Brain Magnetic Resonance Imaging (MRI) | 5.8 percentage of participants |
| Lapatinib and Radiation Therapy | Complete Response (CR) Rate in the Brain at 12 Weeks Post-radiation Therapy (RT) Using the RECIST 1.1 Criteria Based on Brain Magnetic Resonance Imaging (MRI) | 0 percentage of participants |
Comparison: The study was designed to see if there is a signal in the 12-week CR rate with the addition of lapatinib to warrant a future phase III trial. Null hypothesis: the 12-week post-WBRT/SRS CR rate is ≤ 5%; alternative hypothesis: the addition of lapatinib will increase that CR rate to at least 20%. 114 eligible participants provide 86% power to detect a 15% absolute increase in CR rate at a significance level of 0.10, using a 1-sided Z-test for the difference of 2 proportions.p-value: 0.97Z-test
Secondary
Complete Response Rate in the Brain at 4 Weeks Post-RT Using the RECIST 1.1 Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients.
Time frame: Baseline and 4 weeks post RT (approximately 4 weeks from start of treatment if SRS and 7 if WBRT)
Population: Evaluable data for determining the 4-week post-RT RECIST response was available for 55 eligible participants on the RT alone arm and 67 on the lapatinib arm.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Radiation Therapy | Complete Response Rate in the Brain at 4 Weeks Post-RT Using the RECIST 1.1 Criteria Based on Brain MRI | 3.6 percentage of participants |
| Lapatinib and Radiation Therapy | Complete Response Rate in the Brain at 4 Weeks Post-RT Using the RECIST 1.1 Criteria Based on Brain MRI | 1.5 percentage of participants |
p-value: 0.78Z-test
Secondary
Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI
The WHO/modified McDonald Criteria evaluates changes in bidimensional tumor measurements. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Rate is calculated by dividing the number of patients with complete response by the number of analyzable patients.
Time frame: Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT)
Population: Evaluable data for determining the 4- and 12-week post-RT WHO response was available for 55 eligible participants at week 4 and 52 at week 12 on the RT alone arm and 67 at week 4 and 64 at week 12 on the lapatinib arm.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Radiation Therapy | Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI | 4 weeks post-RT | 3.6 percentage of participants |
| Radiation Therapy | Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI | 12 weeks post-RT | 5.8 percentage of participants |
| Lapatinib and Radiation Therapy | Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI | 4 weeks post-RT | 1.5 percentage of participants |
| Lapatinib and Radiation Therapy | Complete Response Rate in the Brain Using the World Health Organization (WHO)/Modified McDonald Criteria Based on Brain MRI | 12 weeks post-RT | 0 percentage of participants |
Comparison: 4 weeks post-RTp-value: 0.78Z-test
Comparison: 12 weeks post-RTp-value: 0.97Z-test
Secondary
Frequency of Highest Treatment-related Adverse Event Per Participant
Adverse events reported as definitely, probably, or possibly related to protocol treatment. Common Terminology Criteria for Adverse Events (version 4.0) grades adverse event severity from 1=mild to 5=death. Summary data provided in this outcome measure. See Adverse Events Module for specific Adverse Event data.
Time frame: From randomization to last follow-up. Maximum follow-up at time of analysis was 71.6 months.
Population: Eligible participants who started study treatment and have adverse event data.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 2 | 23 Participants |
| Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 4 | 0 Participants |
| Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 3 | 5 Participants |
| Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 5 | 0 Participants |
| Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 1 | 8 Participants |
| Lapatinib and Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 5 | 0 Participants |
| Lapatinib and Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 1 | 14 Participants |
| Lapatinib and Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 2 | 20 Participants |
| Lapatinib and Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 3 | 20 Participants |
| Lapatinib and Radiation Therapy | Frequency of Highest Treatment-related Adverse Event Per Participant | Grade 4 | 4 Participants |
Secondary
Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Objective response is defined as a complete or partial response. Complete response is defined as the complete disappearance of all enhancing disease and off all steroids. Partial response is defined as ≥ 30% reduction in the sum of diameters of up to 2 of the largest target lesions. Rate is calculated by dividing the number of patients with objective response by the number of analyzable patients.
Time frame: Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT)
Population: Evaluable data for determining the 4- and 12-week post-RT RECIST response was available for 55 eligible participants at week 4 and 52 at week 12 on the RT alone arm and 67 at week 4 and 64 at week 12 on the lapatinib arm.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Radiation Therapy | Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 4 weeks post-RT | 41.8 percentage of participants |
| Radiation Therapy | Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 12 weeks post-RT | 59.6 percentage of participants |
| Lapatinib and Radiation Therapy | Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 4 weeks post-RT | 55.2 percentage of participants |
| Lapatinib and Radiation Therapy | Objective Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 12 weeks post-RT | 46.9 percentage of participants |
Secondary
Overall Complete Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Overall complete response is defined as the complete disappearance of all CNS target lesions sustained for at least 4 weeks; with no new lesions, no use of corticosteroids, and patient is stable or improved clinically. All site-reported MRI data and all site-reporting of clinical progressive disease indicators were used in this analysis. Rate is calculated by dividing the number of participants with overall complete response by the number of analyzable participants.
Time frame: From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months.
Population: Evaluable data for determining overall post-RT RECIST response was available for 54 eligible participants on the RT alone arm and 68 on the lapatinib arm.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Radiation Therapy | Overall Complete Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 0 Participants |
| Lapatinib and Radiation Therapy | Overall Complete Response Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 0 Participants |
p-value: 1z-test
Secondary
Overall Progression Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Overall progression is defined as unequivocal progression, new or worsening tumor-related neurological symptoms, tumor-related increase in steroid dose, new primary in brain, or progression in target lesions. All site-reported MRI data and all site-reporting of clinical progressive disease indicators were used in this analysis. Rate is calculated by dividing the number of participants with progression by the number of analyzable participants.
Time frame: From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months.
Population: Evaluable data for determining overall post-RT RECIST response was available for 54 eligible participants on the RT alone arm and 68 on the lapatinib arm.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Radiation Therapy | Overall Progression Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 38 Participants |
| Lapatinib and Radiation Therapy | Overall Progression Rate in the Brain Using the RECIST 1.1 Criteria Based on Brain MRI | 54 Participants |
Secondary
Overall Survival (OS)
An event for overall survival is death due to any cause. Survival time is defined as time from randomization to the date of death or last known follow-up (censored). Rates are estimated by the Kaplan-Meier method. Analysis occurred after 101 deaths were reported.
Time frame: From randomization to last follow-up. Maximum follow-up at time of analysis was 71.6 months.
Population: Eligible participants
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Radiation Therapy | Overall Survival (OS) | 15.6 months |
| Lapatinib and Radiation Therapy | Overall Survival (OS) | 15.3 months |
p-value: 0.6795% CI: [0.62, 1.36]Log Rank
Secondary
Percentage of Participants With Progression in the Brain Outside the Targeted Measurable Disease Using the RECIST 1.1 Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. CNS progressive disease outside the targeted measureable disease was determined by a retrospective central review of MRI scans by the study neuroradiology co-chair and is defined as the first occurrence since baseline of new lesions or progression of non-target lesions. Time to CNS progressive disease is defined as time from randomization to the date of progressive disease, last known follow-up (censored), or death (competing risk). Progression rates are estimated using the cumulative incidence method. One-year rates are provided.
Time frame: From randomization to last follow-up. MRIs occurred at baseline, 4 and 12 weeks post RT, then every 12 weeks thereafter until progression. Maximum follow-up at time of analysis was 71.6 months.
Population: MRI scans were available for central review for progression outside targeted measurable disease for 41 eligible participants on the RT alone arm and 57 on the lapatinib arm.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Radiation Therapy | Percentage of Participants With Progression in the Brain Outside the Targeted Measurable Disease Using the RECIST 1.1 Criteria Based on Brain MRI | 22.0 percentage of participants |
| Lapatinib and Radiation Therapy | Percentage of Participants With Progression in the Brain Outside the Targeted Measurable Disease Using the RECIST 1.1 Criteria Based on Brain MRI | 37.7 percentage of participants |
Secondary
Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Objective response is defined as a complete or partial response. Complete response is defined as the complete disappearance of all enhancing disease and partial response is defined as ≥ 30% reduction in the diameter of the target lesion. Lesions were evaluated individually. Rate is calculated by dividing the number of lesions with objective response by the number of analyzable lesions.
Time frame: Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT)
Population: Evaluable data for determining the 4- and 12-week post-RT RECIST target lesion measurement response was available for 51 eligible participants at week 4 and 43 at week 12 on the RT alone arm and 66 at week 4 and 57 at week 12 on the lapatinib arm.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Radiation Therapy | Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 4 weeks post-RT | 51.1 percentage of lesions |
| Radiation Therapy | Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 12 weeks post-RT | 75.0 percentage of lesions |
| Lapatinib and Radiation Therapy | Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 4 weeks post-RT | 56.0 percentage of lesions |
| Lapatinib and Radiation Therapy | Targeted Lesion-specific Objective Response Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 12 weeks post-RT | 61.4 percentage of lesions |
Secondary
Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI
The RECIST criteria evaluates changes in the largest diameter (unidimensional measurement) of the tumor lesions. Progression is defined as ≥ 20% increase in the diameter of the target lesion relative to nadir. Lesions were evaluated individually. Rate is calculated by dividing the number of lesions with progression by the number of analyzable lesions.
Time frame: Baseline, 4 and 12 weeks post RT (approximately 4 and 12 weeks from start of treatment if SRS, 7 and 15 if WBRT)
Population: Evaluable data for determining the 4- and 12-week post-RT RECIST target lesion measurement response was available for 51 eligible participants at week 4 and 43 at week 12 on the RT alone arm and 66 at week 4 and 57 at week 12 on the lapatinib arm.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Radiation Therapy | Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 4 weeks post-RT | 3.3 percentage of lesions |
| Radiation Therapy | Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 12 weeks post-RT | 6.6 percentage of lesions |
| Lapatinib and Radiation Therapy | Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 4 weeks post-RT | 1.7 percentage of lesions |
| Lapatinib and Radiation Therapy | Targeted Lesion-specific Progression Rate Using the RECIST 1.1 Measurement Criteria Based on Brain MRI | 12 weeks post-RT | 14.9 percentage of lesions |