** Shares of drug developer Viking Therapeutics VKTX.O rise 11.7% to $31.67 premarket

** Co plans to advance a tablet form of its experimental weight-loss drug, VK2735, into late-stage studies in the third quarter of this year

** Says data from the mid‑stage study supports its belief that effective weight maintenance may be achieved with a low-dose oral treatment strategy

** Oppenheimer analysts say the regulatory path for VK2735 presents advantages compared to its injectable weight-loss drug program through potentially abbreviated trial duration and smaller trial sizes

** Up to last close, stock down 4.7% YTD