** IDEAYA Biosciences' IDYA.O shares down 7.9% in extended trading to $29 on planned equity raise

** IDYA announces $300 mln offering of stock and pre-funded warrants

** JP Morgan, Jefferies, TD Cowen, UBS and Cantor joint bookrunners

** Co intends to use net offering proceeds for clinical development/potential commercialization of its drug darovasertib for uveal melanoma, advance its broader pipeline of oncology product candidates, and general purposes, per the prospectus

** Last week, IDYA announced clinical collaboration with Swiss pharma giant Roche ROPC.S in combination study in MTAP-deleted RAS-mutant pancreatic cancer

** IDYA shares appeared to get a boost on Mon, closing up 11.3% at $31.48, after Tango Pharmaceuticals' TNGX.O experimental pancreatic cancer drug vopimetostat, in combination with Revolution Medicines' RVMD.O daraxonrasib, showed strong early results in a small study

** With ~87.9 mln shares outstanding, South San Francisco, California-based IDYA has roughly $2.8 bln current market cap

** At Mon close, shares down ~9% YTD

** 17 of 19 analysts rate the stock "strong buy" or "buy", 2 "hold"; median PT $50, according to LSEG data