Lapatinib in Combination With Weekly Paclitaxel in Patients With ErbB2 Amplified Advanced Gastric Cancer

Phase 3

Completed

Conditions: Neoplasms, Gastrointestinal Tract

Interventions: Drug: Lapatinib
Drug: Paclitaxel

Registration Number: NCT00486954

Lead Sponsor: GlaxoSmithKline

Brief Summary: EGF104578 is two-part study (Pilot part/Randomized part).Pilot part is designed to find the optimal (best) doses of lapatinib and paclitaxel when given together,Randomized part is designed to evaluate the overall survival in patients receiving lapatinib and paclitaxel compared to patients receiving only paclitaxel.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 273

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Paclitaxel plus Lapatinib	Lapatinib	6 pills of lapatinib at 250 mg each once daily and infusion of paclitaxel at 80 mglm2 weekly
Paclitaxel plus Lapatinib	Paclitaxel	6 pills of lapatinib at 250 mg each once daily and infusion of paclitaxel at 80 mglm2 weekly
Paclitaxel alone	Paclitaxel	Infusion of paclitaxel at 80 mglm2 weekly

Primary Outcome Measures

Name	Time	Method
Number of Participants With Dose Limiting Toxicities (DLTs) in the Pilot Part of the Study	28 days	DLTs consisted of only drug-related toxicities (neurologic and non-neurologic DLTs). A neurologic DLT was defined as grade 3/4 clinically significant peripheral motor and/or sensitive neuropathy. Non-neurologic DLTs mainly included the following: grade 3/4 clinically significant non-hematological toxicity (except nausea), grade 4 neutropenia lasting \>=7 days, thrombocytopenia (\<=25000 cells per cubic millimeter), inability to begin next treatment within 2 weeks of scheduled dosing due to unresolved toxicity, treatment delay (due to toxicity) of \>5 days, for Days 8 or 15 of weekly paclitaxel.
Overall Survival (OS) in the Randomized Part of the Study	From randomization until death due to any cause (up to 42.58 months)	OS was defined as the time from randomization until death due to any cause. For participants who did not die, time to death was censored at the time of last contact. For censored participants, time to death was defined as the time from randomization to the time of last contact.

Secondary Outcome Measures

Name	Time	Method
Maximum Plasma Concentration (Cmax) of Lapatinib in the Pilot Part of the Study	Days 8 and 14	Pharmacokinetic (PK) samples were collected at pre-dose and at 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 8 and 14.
Time to Cmax (Tmax) of Lapatinib in the Pilot Part of the Study	Days 8 and 14	PK samples were collected at pre-dose and at 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 8 and 14.
Area Under the Concentration-time Curve From Time Zero to 24 Hours (AUC[0-24]) of Lapatinib in the Pilot Part of the Study	Days 8 and 14	PK samples were collected at pre-dose and at 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 8 and 14. AUC is defined as the area under the lapatinib concentration-time curve as a measure of drug exposure. AUC(0-24) is area under the plasma concentration-time curve from time 0 to 24 hours after oral adminisation.
Cmax of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8.
Tmax of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8.
AUC(0-24) of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8. AUC is defined as the area under the paclitaxel concentration-time curve as a measure of drug exposure. AUC(0-24) is area under the plasma concentration-time curve from the start of infusion (time 0) to 24 hours after the start of the infusion.
Area Under the Concentration-time Curve From Time Zero to Infinity (AUC[0-inf]) of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8. AUC is defined as the area under the paclitaxel concentration-time curve as a measure of drug exposure. AUC(0-inf) is area under the plasma concentration-time curve from the start of infusion (time 0) extrapolated to infinity.
Half-life of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8. Half-life is defined as the time required for the amount of the drug in the plasma to decrease by half.
Clearance of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8. Clearance is defined as the clearance of drug from plasma, which is defined as the volume of plasma from which drug is removed per unit time.
Distribution Volume at Steady State (Vss) of Paclitaxel in the Pilot Part of the Study	Days 1 and 8	PK samples were collected just before the start of infusion and 0.5, 1.0 (immediately before terminating the infusion), 1.5, 2, 3, 4, 6, 8, 12, and 24 hours post dose on Days 1 and 8. Vss is the volume of distribution at steady state of paclitaxel.
Progression-free Survival (PFS) in the Randomized Part of the Study	From randomization until disease progression or death due to any cause (up to 42.35 months)	PFS was defined as the time from randomization until the earliest date of disease progression (PD) or death due to any cause. Per Response Evaluation Criteria in Solid Tumors (RECIST), version 1.0, PD is defined as at least a 20% increase in the sum of the longest diameter (LD) of target lesions, taking as reference the smallest sum LD recorded since the treatment started, or the appearance of one or more new lesions.
Time to Progression in the Randomized Part of the Study	From randomization until disease progression or death due to disease (up to 42.35 months )	Time to progression was defined as the time from randomization until the earliest date of disease progression or death due to disease. Per RECIST, version 1.0, PD is defined as at least a 20% increase in the sum of the LD of target lesions, taking as reference the smallest sum LD recorded since the treatment started, or the appearance of one or more new lesions.
Percentage of Participants With Overall Response in the Randomized Part of the Study	From randomization up to 5.62 months	Overall response was defined as the percentage of participants achieving either complete response (CR) or partial response (PR). Per RECIST, version 1.0, CR was defined as the disappearance of all target lesions, and PR was defined as a greater than 30% decrease in the sum of the LD of target lesions, taking as reference the baseline sum LD.
Number of Participants With the Indicated Time to Response in the Randomized Part of the Study	up to 5.62 months	Time to response was defined as the time from randomization to CR (the disappearance of all target lesions) or PR (a greater than 30% decrease in the sum of the LD of target lesions, taking as reference the baseline sum LD). For participants who did not achieve a CR or PR, time to response was censored at the last assessment prior to other cancer therapies. For censored participants, time to response was defined as the time from randomization to the time of the last assessment prior to the administation of other cancer therapies.
Duration of Response in the Randomized Part of the Study	up to 18.27 months	Duration of response was defined as the time from the first documented evidence of CR (the disappearance of all target lesions) or PR (a greater than 30% decrease in the sum of the LD of target lesions, taking as reference the baseline sum LD) until the first documented sign of disease progression (at least a 20% increase in the sum of the LD of target lesions, taking as reference the smallest sum LD recorded since the treatment started, or the appearance of one or more new lesions) or death due to any cause, if sooner.
Number of Participants With the Indicated Grade 3 and Grade 4 Adverse Events (AEs) for Which All Grades of the AE Were Reported in >=10% of Participants, Regardless of Causality in the Randomized Part of the Study	From the first dose of investigational product to 30 days after the last dose (up to 110.3 weeks in the Randomized part)	The Common Terminology Criteria for Advere Events (CTCAE) is a descriptive terminology that can be used for AE reporting. Grade (G) refers to the severity of the AE. The CTCAE displays Grades 1 through 5 with unique clinical descriptions of severity for each AE based on this general guideline: Grade (G) refers to the severity of the AE: G 1, mild AE; G 2, moderate AE; G 3, severe AE; G 4, life-threatening/disabling AE; G 5, death related to the AE.
Change From Baseline in the European Organization for Research and Treatment of Cancer Quality of Life (QOL) Questionnaire (EORTC QLQ-C30) Global Health Status (GHS)/QOL Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Physical Functioning Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Role Functioning Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Emotional Functioning Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Cognitive Functioning Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Social Functioning Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Fatigue Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Nausea and Vomiting Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Pain Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Dyspnea Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Insomnia Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Appetite Loss Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Constipation Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Diarrhea Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-C30 Financial Difficulties Symptom Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-C30 is a 30-item, self-reporting questionnaire assessing 15 domains (5 functional scales \[physical/role/emotional/cognitive/social\]; 9 symptom scales \[fatigue/nausea and vomiting/pain/dyspnea/insomnia/appetite loss/constipation/diarrhea/financial difficulties\]; GHS/QOL scale). Participants assessed most statements on a 4-point scale (1, not at all; 4, very much); two questions used a 7-item scale (1, poor; 7, excellent). Scores were averaged and transformed to a 0-100 scale. A high score indicates both a high/healthy level of functioning and a high level of symptoms/problems.
Change From Baseline in the EORTC QLQ-STO22 Dysphagia Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Pain Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Reflux Symptoms Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Eating Restrictions Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Anxiety Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Dry Mouth Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Taste Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Body Image Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Change From Baseline in the EORTC QLQ-STO22 Hair Loss Scale Score at the End of Therapy in the Randomized Part of the Study	Baseline and end of therapy (up to 42.58 months)	The EORTC QLQ-STO22 is a 22-item, self-reporting instrument consisting of 5 scales and 4 single items to assess health-related quality of life (HRQOL) issues related to dysphagia, eating restrictions, reflux, and abdominal pain, as well as specific symptoms that may occur during chemotherapy or radiation treatment. Scores are averaged and transformed to a 0-100 scale. For the symptom scales and items, a high score is equivalent to worse or more symptoms. In the functional scales, however, a high score is equivalent to better function.
Number of Participants With the Indicated Epidermal Growth Factor Receptor (EGFR) Immunohistochemistry Intensity in the Randomized Part of the Study	Pretreatment	EGFR protein expression on the surface of cells in gastric cancer tissue samples was measured using a moncolonal antibody specific for the extracellular region of EGFR, and the degree of membrane staining was evaluated. 3+ indicates positive EGFR expression; \<3+ indicates negative EGFR expression.
Number of Participants With the Indicated Human Epidermal Growth Factor Receptor 2 (HER2) Immunohistochemistry Intensity in the Randomized Part of the Study	Pretreatment	HER2 protein expression on the surface of cells in gastric cancer tissue samples was measured using a monoclonal antibody specific for the extracellulr region of HER2, and the degree of membrane staining was evaulated. The immunohistochemistry test gives a score of 0 to 3+ and measures the amount of HER2 receptor protein on the surface of cells in a gastric cancer tissue sample. Score of 0 to 1+, "HER2 negative"; score of 2+, "borderline"; score of 3+, "HER2 positive."
Number of Participants With Mutations That May Correlate With Response and Toxicity to Lapatinib	Pretreatment	An inadequate number of tissue samples were obtained; thus, analysis could not be performed.