After-Hours Movers: Biotech And Medtech Stocks Jump On Volume And News

(RTTNews) - A wave of after-hours activity swept through select biotech and medical device names Thursday, with several micro- and mid-cap stocks posting sharp gains following session-end catalysts, volume spikes, or pipeline updates. Below are key price moves and developments from RVPH, PEN, PALI, IOBT, RLYB, and VOR.

Reviva Pharmaceuticals Holdings Inc. (RVPH) extended its explosive rally into after-hours trading Thursday, jumping 18.27% to $0.58 following a 35.1% surge during the regular session. The move came on a staggering volume of over 40.5 million shares, nearly nine times its daily average. RVPH traded between $0.3700 and $0.5338 intraday, and the stock remains well below its 52-week high of $4.28.

With a market cap of $47 million, RVPH is drawing attention for its lead candidate brilaroxazine, which targets neuropsychiatric and respiratory indications, including schizophrenia and pulmonary arterial hypertension. Recent catalysts include participation in investor conferences and a $9 million public offering, positioning the micro-cap biotech for increased visibility and potential volatility.

Penumbra Inc. (PEN) surged 7.97% in after-hours trading Thursday to $273.69, building on a 1.55% gain during the regular session, where it closed at $253.49. The sharp post-close rally follows a relatively quiet day marked by modest volume of 312,377 shares, well below its average of 463,139. PEN has rebounded strongly from its recent lows, now trading near the upper end of its 52-week range of $190.08 - $310.00, with a market cap approaching $9.9 billion.

The company's recent executive reshuffle, promoting Shruthi Narayan to President, may be fueling optimism around its global growth strategy, while its portfolio of thrombectomy and neurovascular devices continues to anchor broader interest in the medical device space.

FY25 Outlook: While reporting Q2 results in July, the company increased its guidance for 2025 total revenue to a range of $1.355 billion - $1.370 billion, which represents 13% to 15% growth over 2024 revenue of $1.195 billion. The company maintained guidance for U.S. Thrombectomy growth of 20% - 21% compared to 2024 levels. The company also maintained guidance for both gross margin and operating margin for the full year 2025.

Palisade Bio Inc. (PALI) jumped 10% in after-hours trading Thursday to $1.87, extending a 29.8% surge during the regular session, where it closed at $1.70. The move follows a burst of activity tied to the company's upsized $138 million public offering, which included full exercise of the overallotment option. Volume spiked to over 20.2 million shares, nearly four times its daily average, while the stock traded between $1.38 and $1.78 intraday.

PALI has rebounded sharply from its 52-week low of $0.53, though it remains well below its high of $4.32. With a market cap of $15.8 million, the company's recent clinical updates on PALI-2108 and its licensing agreements appear to be drawing renewed attention to its pipeline.

IO Biotech Inc. (IOBT) rose 5.08% in after-hours trading Thursday to $0.4571, extending a 22.3% surge during the regular session, where it closed at $0.4350. The move came on heavy volume of 16.7 million shares, nearly four times its daily average.

The company recently provided a regulatory update in which the FDA recommended the company not submit a Biologics License Application (BLA) based on data from the IOB-013 clinical trial. In response, IO Biotech announced plans to design a new registrational study for its cancer vaccine candidate Cylembio, targeting first-line treatment in advanced melanoma. The company also disclosed a restructuring initiative to conserve capital, which includes reducing its workforce by about 50% and incurring a one-time charge of up to $1.5 million in Q3 2025.

Rallybio Corp. (RLYB) jumped 11.2% in after-hours trading Thursday to $0.5688, reversing a modest 1.4% dip during the regular session, where it closed at $0.5116. The late-session move came on relatively light volume of 376,487 shares, well below its daily average of 2.94 million, suggesting a shift in positioning or reaction to recent updates. RLYB has rebounded from its 52-week low of $0.22, though it remains far below its high of $1.24.

The company recently completed dosing in its Phase 1 confirmatory study for RLYB116, targeting complement-mediated disorders, and received a $12.5 million milestone payment from Recursion for progress on the REV102 program. With a market cap of $21.4 million, the stock continues to respond to pipeline developments and strategic collaborations.

Vor Biopharma Inc. (VOR) rose 3.6% in after-hours trading Thursday to $38.00, recovering part of its 6.6% decline during the regular session, where it closed at $36.68. The rebound follows a volatile day that saw the stock swing between $36.67 and $42.75 on volume of 729,338 shares, well above its daily average of 398,178. VOR remains near the midpoint of its 52-week range of $2.62-$65.80, with recent attention centered on its trem-cel platform and CD33-directed therapies for acute myeloid leukemia.

The company has also announced multiple upcoming presentations at immunology and inflammation forums, alongside new executive appointments in medical affairs and legal roles. With a market cap of $251 million, the stock continues to respond to clinical updates and strategic shifts.