Inclusion Criteria:

- Age > 18 years

- A patient who is able to walk and should have ECOG performance status of 0-2.

- Histologically confirmed adenocarcinoma of the stomach or gastro-oesophageal junction
with inoperable locally advanced or recurrent and/or metastatic disease, not amenable
to curative therapy.

- HER2 positive tumour (primary tumour or metastasis defined as 1) 3+ on IHC and/or 2)
FISH (+)

- Failure to at least one chemotherapy regimen

* trastuzumab or lapatinib-pretreated patient is eligible

- Measurable or non-measurable-evaluable disease according to the Response Evaluation
Criteria in Solid Tumors (RECIST)

- Adequate bone marrow function, including:

- Adequate renal function, including:

- Adequate liver function, including:

- Adequate Cardiac Function, including:

1. 12-Lead electrocardiogram (ECG) with normal tracing or non-clinically
significant changes that do not require medical intervention;

2. QTc interval 470 msec and without history of Torsades de Pointes or other
symptomatic QTc abnormality;

3. LVEF (by MUGA or echocardiogram) of ≥50%.

- Brain metastasis allowed if any necessary treatment has been completed and the
patient is radiologically and neurologically stable off corticosteroids at least 2
weeks prior to enrollment

- A patient with the willingness to comply with the study protocol during the study
period and capable of complying with it.

- A patient who signed the informed consent prior to the participation of the study and
who understands that he/she has a right to withdrawal from participation in the study
at any time without any disadvantages.

Exclusion Criteria:

- Patients with known active brain metastases or any leptomeningeal metastases;

a. Patients with previously diagnosed brain metastases for which treatment (radiation
or surgery) is recommended in judgment of investigator are eligible if they have
completed their CNS treatment and have recovered from the acute effects of radiation
therapy or surgery prior to the start of study medication, have discontinued
corticosteroid treatment for these metastases for at least 2 weeks and are
neurologically stable.

- Radiotherapy (other than palliative radiotherapy to lesions that will not be followed
for tumor assessment on this study, ie, non-target lesions), biological or
investigational agents within 2 weeks of baseline disease assessments

- Any surgery (not including minor procedures) within 4 weeks of baseline disease
assessments; or not fully recovered from any side effects of previous procedures;

- Any clinically significant gastrointestinal abnormalities, which may impair intake,
transit or absorption of the study drug, such as the inability to take oral
medication in tablet form;

- Current enrollment in another therapeutic clinical trial;

- Any psychiatric or cognitive disorder that would limit the understanding or rendering
of informed consent and/or compromise compliance with the requirements of this
protocol

- Patients with known interstitial lung disease;

- Uncontrolled or significant cardiovascular disease

- Prior malignancy: Patients will not be eligible if they have evidence of other
malignancy (other than non-melanoma skin cancer or in situ cervical cancer, or
localized and presumed cured prostate cancer with PSA < ULN) within the last 5 years.

- Organ allogenic transplantation requiring immunosuppressive therapy.

- A patient who developed uncontrolled serious infection or other uncontrolled serious
concomitant diseases.