Prothena - 13 Year Stock Price History | PRTA

The latest closing stock price for Prothena as of June 03, 2025 is 4.83.

  • An investor who bought $1,000 worth of Prothena stock at the IPO in 2012 would have $-329 today, roughly 0 times their original investment - a -3.27% compound annual growth rate over 12 years.
  • The all-time high Prothena stock closing price was 78.89 on September 23, 2021.
  • The Prothena 52-week high stock price is 25.42, which is 426.3% above the current share price.
  • The Prothena 52-week low stock price is 4.32, which is 10.6% below the current share price.
  • The average Prothena stock price for the last 52 weeks is 15.88.
For more information on how our historical price data is adjusted see the Stock Price Adjustment Guide.

Prothena - 13 Year Stock Price History | PRTA

  • An investor who bought $1,000 worth of Prothena stock at the IPO in 2012 would have $-329 today, roughly 0 times their original investment - a -3.27% compound annual growth rate over 12 years.
  • The all-time high Prothena stock closing price was 78.89 on September 23, 2021.
  • The Prothena 52-week high stock price is 25.42, which is 426.3% above the current share price.
  • The Prothena 52-week low stock price is 4.32, which is 10.6% below the current share price.
  • The average Prothena stock price for the last 52 weeks is 15.88.
For more information on how our historical price data is adjusted see the Stock Price Adjustment Guide.