Biotech After-Hours Frenzy: 6 Stocks Making Moves on Friday Night

While most traders were winding down Friday, biotech stocks were just getting started. Here’s what went down in after-hours trading on November 21, 2025:

The Gainers:

Butterly Network (BFLY) didn’t stop at its impressive 14.22% daily close—it kept climbing 6.04% after hours to $2.81. The digital health company is hyping its handheld ultrasound tech ahead of the Evercore Healthcare Conference in December, where CEO Joseph DeVivo will host investor meetings.

Citius Pharma (CTXR) was the star performer, surging 15.15% at close to $1.14, then adding another 7.90% after hours to $1.23. The catalyst? Its oncology subsidiary deepened ties with Verix to commercialize LYMPHIR (denileukin diftitox-cxdl), a newly FDA-approved immunotherapy for cutaneous T-cell lymphoma hitting shelves Q4 2025.

Tempest Therapeutics (TPST) flipped the script—down 4.89% at close but bouncing back 4.86% after hours to $3.67. The reason: earlier this week they announced acquiring CAR-T programs from Factor Bioscience, adding TPST-2003 (a CD19/BCMA dual-CAR T therapy) to their pipeline and securing runway through mid-2027.

The Others:

ProQR (PRQR) climbed 6.80% to $2.20 with no news catalyst—pure sentiment trading. Perrigo (PRGO) edged up 3.97% to $13.14, extending its daily gain. Iterum (ITRM) and Processa (PCSA) made modest moves (+2.77% and +1.86% respectively) with no fresh developments.

The Takeaway: When biotech gets a catalyst—whether it’s new partnerships, pipeline additions, or investor conferences—the after-hours crowd shows up. Watch CTXR and BFLY closer; they’ve got real catalysts brewing.