Betta Pharmaceuticals shares tumbled to their 20% daily limit on August 18 after partner EYPT reported that the Phase 3 LUGANO study of co-developed eye drug DURAVYU failed to show non-inferiority to aflibercept in wet age-related macular degeneration, or wAMD. Betta's stock dropped to 55.72 yuan within minutes of the open and stayed pinned there through the midday break, cutting its market value to 23.59 billion yuan, about $3.5 billion. EYPT, which is listed on Nasdaq, fell 66.78% after releasing the top-line data on August 17. The setback matters because anti-VEGF (drugs that block abnormal blood vessel growth) therapies dominate wAMD treatment, and aflibercept is a leading product in that market. Betta said another Phase 3 trial, LUCIA, is still under way and that any regulatory filing route in China will depend on those results and talks with regulators. The company added that milestone payments and related economics will be handled under later project progress and the parties' agreement, leaving the program's commercial outlook unresolved.