This is an double-blind, single dose, four-period, crossover study in Japanese healthy male volunteers to assess the pharmacokinetics and safety/tolerability of single doses of GSK1605786A. Approximately 24 subjects will receive three treatments of 250, 500, and 1000mg GSK1605786 under fasted conditions or 500mg after food intake plus placebo in a dose ascending crossover design. Serial pharmacokinetic samples will be collected following each dose and safety assessments will be performed. The pharmacokinetics and dose proportionality of GSK1605786 after single oral doses of GSK1605786 at the dose levels of 250mg, 500mg and 1000 mg under fasted conditions will be assessed. In addition, a comparison will be made between the pharmacokinetics of GSK1605786 under fed and fasted conditions.

Inclusion Criteria:

• Healthy Japanese as
• Japanese defined as being born in Japan, having four ethnic Japanese grandparents, holding a Japanese passport or identity -Male between 20 and 55 years of age inclusive, at the time of signing the informed consent.
• Body weight =>50kg and BMI within the range 18.5 - 25 kg/m2 (inclusive).

Exclusion Criteria:

- Known coeliac disease or positive serologic testing for anti-tTG antibodies (required to screen for undiagnosed celiac disease)