Corteva (NYSE: CTVA), OpenWorld (NASDAQ: OPNW), Nektar Therapeutics (NASDAQ: NKTR), Agomab Therapeutics (NASDAQ: AGMB), and Agenus (NASDAQ: AGEN) posted steep one-day losses on October 1, 2026. Most of the drops are not clearly tied to the day’s headlines.
Corteva (NYSE: CTVA) closed 83.8% lower at $12.57, mainly because it completed the Vylor spinoff and shareholders received one Vylor share per Corteva share. States also sued Corteva and Vylor over alleged efforts to limit “forever chemicals” liabilities.
OpenWorld (NASDAQ: OPNW) fell 25.9% to $5.54 as it began trading under OPNW and said it intends to acquire Blocksight, pending board approval. That plan is not confirmed as the cause of the drop.
Nektar Therapeutics (NASDAQ: NKTR) declined 22.4% to $46.99 despite presenting REZPEG alopecia and dermatitis data at EADV 2026. No cause is confirmed.
Agomab Therapeutics (NASDAQ: AGMB) dropped 22.1% to $8.65 after positive 48-weekontunisertib data in fibrostenotic Crohn’s disease.
Agenus (NASDAQ: AGEN) fell 16.1% to $8.33 ahead of a planned three-year survival presentation for botensilimab plus balstilimab in recurrent ovarian cancer. Neither clinical update is established as the reason for the decline.
