Neoplasms, Breast
Conditions
Keywords
lapatinib, advanced, metastatic breast cancer, GW572016, ErbB2
Brief summary
This phase II study will evaluate and compare the efficacy and tolerability of two dose schedules (1500 mg QD and 500 mg BID) of oral Lapatinib as treatment for patients with advanced or metastatic breast cancer.
Interventions
Sponsors
Study design
Eligibility
Inclusion criteria
* Histologically confirmed invasive breast cancer with incurable stage IIIB, IIIC with T4 lesion or stage IV disease at primary diagnosis or at relapse after curative intent surgery. * Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1. * Documented amplification of ErbB2 by Fluorescence in situ hybridization (FISH) * Measurable disease by Response Evaluation Criteria In Solid Tumors (RECIST) * Adequate renal, hepatic and cardiac function
Exclusion criteria
* Prior chemotherapy, immunotherapy, biologic therapy or anti-ErbB1/ErbB2 therapy other than adjuvant therapy. \[Prior neo-adjuvant or adjuvant therapy (including trastuzumab) will be allowed provided it was stopped at least 12 months before study entry. * Patients with active brain metastases * Patients with bilateral breast cancer, bone metastases as the only disease site or metastases to more than 30% of the hepatic parenchyma.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC) | From the date of the first dose of investigational product to the first documented evidence of a confirmed CR or PR (up to Study Week 103) | OR is defined as the number of participants achieving either a confirmed CR or PR, per Response Evaluation Criteria in Solid Tumors (RECIST, v 1.0). Best OR is defined as the best response recorded from the start of treatment until progressive disease (PD)/recurrence. CR is defined as the disappearance of all target lesions (TLs) and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s), as assessed by the IRC. PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. Responses were confirmed at subsequent assessments made \>=28 days after the original response. Participants with an unknown or missing response are treated as non-responders. |
| Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator | From the date of the first dose of investigational product to the first documented evidence of a confirmed CR or PR (up to Study Week 103) | OR is defined as the number of participants achieving either a confirmed CR or PR, per Response Evaluation Criteria in Solid Tumors (RECIST, v 1.0). Best OR is defined as the best response recorded from the start of treatment until progressive disease (PD)/recurrence. CR is defined as the disappearance of all target lesions (TLs) and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s), as assessed by the IRC. PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. Responses were confirmed at subsequent assessments made \>=28 days after the original response. Participants with an unknown or missing response are treated as non-responders. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Duration of Response (DoR), as Assessed by the IRC and Investigator | From the first documented evidence of a PR or CR until the earlier of the date of disease progression or the date of death due to breast cancer (up to Study Week 103) | DoR is defined for the subset of par. who had a confirmed CR (disappearance of all target lesions (TLs) and non-TLs) or PR (at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of \>= 1 non-TL\[s\]) as the time from the first documented evidence of a CR or PR until the first documentation of radiological PD or death due to breast cancer, if sooner. PD is defined as \>=20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. For par. who did not progress or die, DoR was censored on the date of the last radiological scan. If a par.had only a Baseline visit or did not have a date of a radiological scan that was later than the date of initiation of anti-cancer therapy, DoR was censored at the start date of treatment. |
| Progression-free Survival, as Assessed by the IRC and Investigator | From the date of the first dose of investigational product until the earlier of the date of disease progression or death due to any cause (up to Study Week 103) | Progression-free survival is defined as the time from randomization until the earliest date of disease progression or death due to any cause, if sooner. Disease progression was based on the IRC's and investigator's assessments of the objective evidence (e.g., radiological scans and medical photographs). For participants who did not progress, or die, progression-free survival was censored at the time of the last IRC assessed radiological scan. |
| Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator | From the date of the first dose of investigational product until the date of disease progression or death due to breast cancer (up to Study Week 103) | Clinical benefit is defined as the numer of participants achieving either a confirmed CR (disappearance of all target lesions (TLs) and non-TLs) or PR (at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD,or complete resolution of TLs and the persistence of one or more non-TLs)or SD (neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease \[at least a 20% increase in the sum of the LD of target lesions, taking as a reference, the smallest sum LD recorded since the treatment started or the appearance of 1 or more new TLs or non-TLs and/or unequivocal progressionn of existing non-target lesions\], taking as reference, the smallest sum LD since the treatment started) for at least 24 weeks. This was based on confirmed responses from the investigator assessment of clinical benefit. |
| Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE) | From the date of the first dose of investigational product until 30 days after the last dose of investigational product (up to study week 192) | An AE is defined as any untoward medical occurrence in a participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is defined as any untoward medical occurrence that, at any dose, results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or is a congenital anomaly/birth defect. Medical or scientific judgment was exercised in deciding whether reporting was appropriate in other situations. Refer to the general AE/SAE module for a list of non-serious AEs and SAEs. |
| Time to Treatment Failure, as Assessed by IRC and Investigator | From randomization until the first documented sign of disease progression, death due to any cause, or early discontinuation from investigational product (up to Study Week 103) | Time to treatment failure is calculated as the interval between the date of randomization and the occurrence of local tumor progression (including ipsilateral \[on the same side\] and controlateral breast tumor progression), distant tumor progression, permanent treatment discontinuation (either for the experimental or conventional treatment arm), or death due any cause. For participants who did not progress, die or discontinue early, time to treatment failure was censored at the last scan date. |
| Time to Response, as Assessed by the IRC and Investigator | From the date of the first dose of investigational product until the first documented evidence of a PR or CR (up to Study Week 103) | Time to response is defined as the time from randomization until the first documented evidence of a PR or CR (whichever status is recorded first). Analysis was based on responses confirmed at a repeat assessment made at least 4 weeks after the initial response, with the time to response taken as the first time the response was observed, not the confirmation assessment. Participants who withdraw with no tumor response were censored at the date of withdrawal from the study. CR is defined as the disappearance of all TLs and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameter (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s). PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of one or more new lesions or unequivocal progression of existing non-TLs. |
Countries
Chile, Hong Kong, India, Malaysia, Mexico, Pakistan, Peru, Poland, Singapore, Taiwan, United States
Participant flow
Recruitment details
Participants (par.) with histologically confirmed invasive breast cancer with incurable stage IIIb, stage IIIc with T4 lesion, or stage IV disease at primary diagnosis or at relapse after curative-intent surgery and whose tumors overexpressed ErbB2 protein, documented by FISH were eligible for inclusion in this phase II study.
Participants by arm
| Arm | Count |
|---|---|
| Lapatinib 1500 mg QD Participants received lapatinib 1500 mg orally QD. Treatment was continued for 12 weeks or until disease progression or withdrawal from treatment for another reason. After Week 12, participants with clinical benefit had the option to continue with the lapatinib therapy at the same dose and schedule, until disease progression, provided the treatment was tolerated. | 69 |
| Lapatinib 500 mg BID Participants received lapatinib 500 mg orally BID. Treatment was continued for 12 weeks or until disease progression or withdrawal from treatment for another reason. After Week 12, participants with clinical benefit had the option to continue with the lapatinib therapy at the same dose and schedule, until disease progression, provided the treatment was tolerated. | 69 |
| Total | 138 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 4 | 7 |
| Overall Study | Clinical Progression | 1 | 2 |
| Overall Study | Death | 3 | 3 |
| Overall Study | Lost to Follow-up | 2 | 1 |
| Overall Study | Patient Underwent Surgery | 2 | 0 |
| Overall Study | Physician Decision | 2 | 2 |
| Overall Study | Poor General Condition | 1 | 0 |
| Overall Study | Radiological Progression of Cancer | 52 | 44 |
| Overall Study | Skin Nodule Over Right Mastectomy | 0 | 1 |
| Overall Study | Symptomatic Progression of Cancer | 2 | 5 |
| Overall Study | Withdrawal by Subject | 0 | 4 |
Baseline characteristics
| Characteristic | Lapatinib 1500 mg QD | Lapatinib 500 mg BID | Total |
|---|---|---|---|
| Age, Continuous | 53.2 Years STANDARD_DEVIATION 14.27 | 53.4 Years STANDARD_DEVIATION 13.66 | 53.3 Years STANDARD_DEVIATION 13.92 |
| Gender Female | 69 Participants | 69 Participants | 138 Participants |
| Gender Male | 0 Participants | 0 Participants | 0 Participants |
| Race/Ethnicity, Customized American Hispanic | 31 Participants | 32 Participants | 63 Participants |
| Race/Ethnicity, Customized Asian | 36 Participants | 35 Participants | 71 Participants |
| Race/Ethnicity, Customized Black | 0 Participants | 1 Participants | 1 Participants |
| Race/Ethnicity, Customized White | 2 Participants | 1 Participants | 3 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 58 / 69 | 53 / 69 |
| serious Total, serious adverse events | 15 / 69 | 18 / 69 |
Outcome results
Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC)
OR is defined as the number of participants achieving either a confirmed CR or PR, per Response Evaluation Criteria in Solid Tumors (RECIST, v 1.0). Best OR is defined as the best response recorded from the start of treatment until progressive disease (PD)/recurrence. CR is defined as the disappearance of all target lesions (TLs) and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s), as assessed by the IRC. PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. Responses were confirmed at subsequent assessments made \>=28 days after the original response. Participants with an unknown or missing response are treated as non-responders.
Time frame: From the date of the first dose of investigational product to the first documented evidence of a confirmed CR or PR (up to Study Week 103)
Population: Intent-to-Treat (ITT) Population: all randomized participants who received at least one dose of investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC) | CR | 0 Participants |
| Lapatinib 1500 mg QD | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC) | PR | 15 Participants |
| Lapatinib 500 mg BID | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC) | CR | 0 Participants |
| Lapatinib 500 mg BID | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Independent Review Committee (IRC) | PR | 18 Participants |
Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator
OR is defined as the number of participants achieving either a confirmed CR or PR, per Response Evaluation Criteria in Solid Tumors (RECIST, v 1.0). Best OR is defined as the best response recorded from the start of treatment until progressive disease (PD)/recurrence. CR is defined as the disappearance of all target lesions (TLs) and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s), as assessed by the IRC. PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. Responses were confirmed at subsequent assessments made \>=28 days after the original response. Participants with an unknown or missing response are treated as non-responders.
Time frame: From the date of the first dose of investigational product to the first documented evidence of a confirmed CR or PR (up to Study Week 103)
Population: ITT Population
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator | CR | 1 Participants |
| Lapatinib 1500 mg QD | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator | PR | 16 Participants |
| Lapatinib 500 mg BID | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator | CR | 2 Participants |
| Lapatinib 500 mg BID | Number of Participants With a Best Overall Response (OR) of Confirmed Complete Response (CR) or Partial Response (PR), as Assessed by the Investigator | PR | 20 Participants |
Duration of Response (DoR), as Assessed by the IRC and Investigator
DoR is defined for the subset of par. who had a confirmed CR (disappearance of all target lesions (TLs) and non-TLs) or PR (at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of \>= 1 non-TL\[s\]) as the time from the first documented evidence of a CR or PR until the first documentation of radiological PD or death due to breast cancer, if sooner. PD is defined as \>=20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of \>= 1 new lesions or unequivocal progression of existing non-TLs. For par. who did not progress or die, DoR was censored on the date of the last radiological scan. If a par.had only a Baseline visit or did not have a date of a radiological scan that was later than the date of initiation of anti-cancer therapy, DoR was censored at the start date of treatment.
Time frame: From the first documented evidence of a PR or CR until the earlier of the date of disease progression or the date of death due to breast cancer (up to Study Week 103)
Population: ITT Population. Only those participants with CR or PR were analyzed (represented by n=X in the category titles). Different participants may have been analyzed by the IRC and the Investigator, so the overall number of participants analyzed reflects everyone in the ITT Population.
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Duration of Response (DoR), as Assessed by the IRC and Investigator | IRC,n=15, 18 | 27.6 Weeks |
| Lapatinib 1500 mg QD | Duration of Response (DoR), as Assessed by the IRC and Investigator | Investigator, n=17, 22 | 27.6 Weeks |
| Lapatinib 500 mg BID | Duration of Response (DoR), as Assessed by the IRC and Investigator | IRC,n=15, 18 | 29.0 Weeks |
| Lapatinib 500 mg BID | Duration of Response (DoR), as Assessed by the IRC and Investigator | Investigator, n=17, 22 | 29.0 Weeks |
Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE)
An AE is defined as any untoward medical occurrence in a participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is defined as any untoward medical occurrence that, at any dose, results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or is a congenital anomaly/birth defect. Medical or scientific judgment was exercised in deciding whether reporting was appropriate in other situations. Refer to the general AE/SAE module for a list of non-serious AEs and SAEs.
Time frame: From the date of the first dose of investigational product until 30 days after the last dose of investigational product (up to study week 192)
Population: Safety Population: all randomized participants who received at least one dose of investigational product.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE) | Any AE | 65 Participants |
| Lapatinib 1500 mg QD | Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE) | Any SAE | 15 Participants |
| Lapatinib 500 mg BID | Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE) | Any AE | 61 Participants |
| Lapatinib 500 mg BID | Number of Participants With Any Adverse Event (AE) or Serious Adverse Event (SAE) | Any SAE | 18 Participants |
Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator
Clinical benefit is defined as the numer of participants achieving either a confirmed CR (disappearance of all target lesions (TLs) and non-TLs) or PR (at least a 30% decrease in the sum of the longest diameters (LD) of TLs, taking as a reference the Baseline sum LD and no PD,or complete resolution of TLs and the persistence of one or more non-TLs)or SD (neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease \[at least a 20% increase in the sum of the LD of target lesions, taking as a reference, the smallest sum LD recorded since the treatment started or the appearance of 1 or more new TLs or non-TLs and/or unequivocal progressionn of existing non-target lesions\], taking as reference, the smallest sum LD since the treatment started) for at least 24 weeks. This was based on confirmed responses from the investigator assessment of clinical benefit.
Time frame: From the date of the first dose of investigational product until the date of disease progression or death due to breast cancer (up to Study Week 103)
Population: ITT Population
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator | IRC | 29.0 Percentage of Participants |
| Lapatinib 1500 mg QD | Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator | Investigator | 29.0 Percentage of Participants |
| Lapatinib 500 mg BID | Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator | IRC | 33.3 Percentage of Participants |
| Lapatinib 500 mg BID | Percentage of Participants With Clinical Benefit (CR or PR or Stable Disease [SD] for at Least 24 Weeks), as Assessed by the IRC and Investigator | Investigator | 40.6 Percentage of Participants |
Progression-free Survival, as Assessed by the IRC and Investigator
Progression-free survival is defined as the time from randomization until the earliest date of disease progression or death due to any cause, if sooner. Disease progression was based on the IRC's and investigator's assessments of the objective evidence (e.g., radiological scans and medical photographs). For participants who did not progress, or die, progression-free survival was censored at the time of the last IRC assessed radiological scan.
Time frame: From the date of the first dose of investigational product until the earlier of the date of disease progression or death due to any cause (up to Study Week 103)
Population: ITT Population
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Progression-free Survival, as Assessed by the IRC and Investigator | IRC | 19.6 Weeks |
| Lapatinib 1500 mg QD | Progression-free Survival, as Assessed by the IRC and Investigator | Investigator | 17.6 Weeks |
| Lapatinib 500 mg BID | Progression-free Survival, as Assessed by the IRC and Investigator | IRC | 24.4 Weeks |
| Lapatinib 500 mg BID | Progression-free Survival, as Assessed by the IRC and Investigator | Investigator | 20.3 Weeks |
Time to Response, as Assessed by the IRC and Investigator
Time to response is defined as the time from randomization until the first documented evidence of a PR or CR (whichever status is recorded first). Analysis was based on responses confirmed at a repeat assessment made at least 4 weeks after the initial response, with the time to response taken as the first time the response was observed, not the confirmation assessment. Participants who withdraw with no tumor response were censored at the date of withdrawal from the study. CR is defined as the disappearance of all TLs and non-TLs. PR is defined as at least a 30% decrease in the sum of the longest diameter (LD) of TLs, taking as a reference the Baseline sum LD and no PD, or complete resolution of TLs and the persistence of one or more non-TL(s). PD is defined as at least a 20% increase in the sum of the LD of TLs, taking as a reference the smallest sum LD recorded since the treatment started or the appearance of one or more new lesions or unequivocal progression of existing non-TLs.
Time frame: From the date of the first dose of investigational product until the first documented evidence of a PR or CR (up to Study Week 103)
Population: ITT Population. Only those participants with CR or PR were analyzed (represented by n=X in the category titles). Different participants may have been analyzed by the IRC and the Investigator, so the overall number of participants analyzed reflects everyone in the ITT Population.
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Time to Response, as Assessed by the IRC and Investigator | IRC, n=15, 18 | 7.9 Weeks |
| Lapatinib 1500 mg QD | Time to Response, as Assessed by the IRC and Investigator | Investigator, n=17, 22 | 8.0 Weeks |
| Lapatinib 500 mg BID | Time to Response, as Assessed by the IRC and Investigator | IRC, n=15, 18 | 7.9 Weeks |
| Lapatinib 500 mg BID | Time to Response, as Assessed by the IRC and Investigator | Investigator, n=17, 22 | 8.0 Weeks |
Time to Treatment Failure, as Assessed by IRC and Investigator
Time to treatment failure is calculated as the interval between the date of randomization and the occurrence of local tumor progression (including ipsilateral \[on the same side\] and controlateral breast tumor progression), distant tumor progression, permanent treatment discontinuation (either for the experimental or conventional treatment arm), or death due any cause. For participants who did not progress, die or discontinue early, time to treatment failure was censored at the last scan date.
Time frame: From randomization until the first documented sign of disease progression, death due to any cause, or early discontinuation from investigational product (up to Study Week 103)
Population: ITT Population
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Lapatinib 1500 mg QD | Time to Treatment Failure, as Assessed by IRC and Investigator | IRC | 15.7 Weeks |
| Lapatinib 1500 mg QD | Time to Treatment Failure, as Assessed by IRC and Investigator | Investigator | 12.3 Weeks |
| Lapatinib 500 mg BID | Time to Treatment Failure, as Assessed by IRC and Investigator | IRC | 17.0 Weeks |
| Lapatinib 500 mg BID | Time to Treatment Failure, as Assessed by IRC and Investigator | Investigator | 16.1 Weeks |