This is an open-label, randomized, controlled, single center study to assess the safety, variability in exposure, and relative bioavailability of new oral formulations of SRT2104. This is a two part study and each part consists of screening (within 21 days of the first scheduled dose of SRT2104), treatment period and follow-up visit (approximately 6 days after the last dose). Part 1: Subjects will receive all four fomulations of SRT2104 and their order of their doses will be randomized. Each subject will receive one formulation as a 500 milligram (mg) dose (in the form of two 250 mg capsules or tablets) in each session given in the fasted state. Each dose will be separated by at least 6 days. Pharmacokinetic (PK) sampling will be done pre and post each scheduled dosing session. After all 4 dosing sessions, the safety and PK data will be reviewed to determine which, if any, formulation(s) will be carried forward into Part 2. The total duration will be approximately 7 weeks. Part 2: Is further divided into Part 2A, 2B and 2C of the study and are optional. After the completion of Part 1, the sponsor will decide whether to proceed with any or all of Part 2, and whether the selected formulation(s) is to be administered in the fed or fasted state for Parts 2B and 2C. For all the sub parts of Part 2 the pre and post-dose PK samples will be obtained. Part 2A: A single-dose of the selected formulation(s) from Part 1 will be administered after a standard meal to assess the effect of food on the bioavailability of SRT2104 at the 500 mg dose. The total duration will be approximately 4 weeks. Part 2B: A single alternative dose (other than 500 mg, but not to exceed 2000 mg) of the selected formulation(s) from Part 1 will be administered to assess the safety and PK profile of this dose level. The total duration will be approximately 4 weeks. Part 2C: The selected formulation(s) from Part 1 will be administered at the 500 mg dose once daily for 7 consecutive days, to assess the safety and tolerability and characterize the PK profile of repeat dosing. The total duration will be approximately 5 weeks.