In San Francisco on December 30, 2025, Rezolute, Inc. (NASDAQ: RZLT) experienced a significant drop in share price, plummeting by as much as 90% on December 11, 2025. This sudden decline came following the announcement of the unsuccessful Phase 3 sunRIZE trial results for ersodetug (known as "erso"). The company faced challenges as investors grappled with the news, marking a substantial setback in the company's journey.