Ultragenyx is trading 10% up at $28.86 after closing at $26.24 on August 19, 2026, with no verified company-specific announcement released after the regular session to explain the move.

  • Investors await the FDA’s decision by August 23 on DTX401; available reporting discusses prior weakness ahead of that decision rather than attributing the gain to it.
  • The broader market was only modestly higher, so its influence is unclear.