** Vertex Pharmaceuticals' VRTX.O shares rise 6% to $488.52 premarket after co says its late-stage trial for a kidney drug was successful and that it will seek U.S. approval

** The drug, povetacicept, is for IgA nephropathy and reduced a key sign of kidney damage by 52% after 36 weeks, compared with a 4.3% decline for placebo - VRTX

** BMO Capital Markets analysts say results position drug as a "clear competitor and potential leader," comparing favorably to drugs from Otsuka 4768.T and Vera Therapeutics VERA.O

** Stock recently traded at 24 times forward earnings, near its five-year average of 22, suggesting it may be close to fairly valued, per LSEG data

** VRTX's pre-market price is ~6% below its all-time intraday high of $519.68 recorded a year ago

** Median analysts' price target for the stock is $554