Merck rises after Wells Fargo upgrades stock to 'overweight'

** Shares of drugmaker Merck MRK up 2.3% at $100.15 premarket

** Wells Fargo upgrades rating on stock to "overweight" from "equal weight"; raises PT to $125 from $90

** Brokerage says recent business development and pipeline progress reduce risk of revenue cliff after Keytruda loss of exclusivity; sees growth into early 2030s

** Notes MRK added or de-risked more than $20 bln in unadjusted peak sales opportunities in past 3-6 months, including Cidara CDTX acquisition and positive Cadence data

** Expects catalysts over next 12-18 months across oncology, HIV and cardiovascular programs; pipeline can support more than $50 bln peak sales unadjusted

** As of last close, MRK shares down 1.73% YTD