0824 ET - Moderna shares surging 176% on Wednesday may have been an overreaction from Wall Street to the strong results from Moderna and Merck's mRNA-based vaccine for melanoma patients, UBS analysts say. Moderna's valuation jumped to $70 billion; ascribing a modest valuation to the company's Covid-19 revenue, that would imply a $60 billion valuation to the vaccine alone, which would have to translate to $20 billion in annual sales, the analysts say. That could be unrealistically high, they say. The analysts maintain a $150 price target for Moderna after it closed at $174 on Wednesday. Shares slide 10% to $156.30 premarket.