**Strong investor demand for ADARx Pharmaceuticals’ upsized IPO, which priced at the top of its $15–$17 range on September 24, 2026, and raised $446.3 million through the sale of 26.25 million shares, underpins the market-implied odds of a $2B–$2.25B closing market cap at 97.5%.** The San Diego-based siRNA developer benefited from AbbVie’s concurrent private placement for a ~4.9% stake, building on a prior $335 million collaboration, alongside a late-stage pipeline highlighted by onvuzosiran in Phase 3 for hereditary angioedema with top-line data expected by late 2027. Shares opened at $22.10 on Nasdaq debut before settling near levels consistent with roughly $2 billion valuation amid broader biotech IPO momentum. Realistic challenges include disappointing post-IPO trading volume or price action, clinical or regulatory setbacks, or a sector-wide pullback that compresses multiples for clinical-stage biotechs.