Key Takeaways
- • Biotech's October 2026 selloff is driven by mechanics rather than fundamentals, with sell-side analysts Brian Skorney, Paul Matteis, and Jeroen Verber calling it the largest hedge fund "degrossing" in more than five years, per the Biotech Hangout podcast.
- • The XBI has fallen roughly 700 basis points in two weeks to about 146 from a late-August high of 169, though it remains up about 20% year to date.
- • Verber identifies two relief valves: the October 31 annual close for many funds and the November midterm elections, while all three analysts see M&A as the most plausible catalyst to restore buyer demand.
- • Bristol Myers Squibb's positive phase 3 IPF data drew a sharp market reaction, with Contineum rising 20% pre-market before closing down more than 25%, while Argenx terminated its VivGuard phase 3 for futility.
- • Verber advises biotech issuers to list only with a near-term catalyst, as roughly 28 biotechs have IPO'd in 2026 so far.
Summary
Biotech's painful October selloff is driven by positioning rather than deteriorating science, according to sell-side analysts Brian Skorney, Paul Matteis, and Jeroen Verber speaking on the Biotech Hangout podcast. The analysts describe the sector as undergoing the largest hedge fund degrossing in more than five years, a forced deleveraging cycle in which funds sell longs and buy back shorts without a fundamental view. The XBI remains up about 20% year to date but has fallen roughly 700 basis points in two weeks to around 146, down from a late-August high of 169. Pressure dates to June 2026, when hedge funds began cutting total exposure. Because biotech's specialist investor base is small, forced selling in one fund hits positions held by another, which then reduces its own exposure, creating a self-reinforcing spiral. Verber said many fund managers describe this as "the worst environment they've ever seen in their career." Verber added that roughly 99% of volume in the space is now ETF-driven, and that the market punishes even good data.
The analysts identify two dated relief valves. Verber expects degrossing pressure to abate after the October 31 annual close for many funds, and he points to the November midterm elections. He also flags rising interest rates, with at least one more hike expected by year-end and possibly two. All three analysts identify M&A as the catalyst most likely to create the fear of missing out that brings buyers back. Matteis warned that investors are reluctant to buy into weakness, saying "the market is not patient" and that the decline could extend another 10% to 15%.
Clinical developments added to the uncertainty. Bristol Myers Squibb reported positive phase 3 data for its LPA1 receptor antagonist in idiopathic pulmonary fibrosis, though the low dose reached statistical significance while the high dose did not. Contineum, which Matteis covers, rose 20% pre-market before closing down more than 25%. Argenx terminated its VivGuard phase 3 in Sjögren's on futility, hours after a bullish panel at a Boston symposium. Arrowhead reported first clinical data for a transferrin-conjugated siRNA showing up to more than 80% tau lowering in CSF, though analysts noted CSF tau may not reflect brain tau burden. Mirum reported positive phase 3 data for Livmarli across pediatric cholestatic diseases, mostly biliary atresia.
IPO activity continues, with roughly 28 biotechs listed in 2026 and on pace for 30 or more, according to the analysts. Verber advised issuers to go public only with a near-term catalyst. Recent offerings included TRex Bio ($117M gross proceeds), Iambic Therapeutics ($150M), and Citi Therapeutics ($200M, upsized). Elektor raised $75 million the morning after an R&D event. In oncology, the Moderna-Merck mRNA cancer vaccine data announced in August 2026 showed a significant progression-free survival benefit in melanoma, though Jake Becraft noted the control was a null placebo rather than a non-antigen-specific mRNA vaccine, which complicates attribution of benefit.
The analysts identify two dated relief valves. Verber expects degrossing pressure to abate after the October 31 annual close for many funds, and he points to the November midterm elections. He also flags rising interest rates, with at least one more hike expected by year-end and possibly two. All three analysts identify M&A as the catalyst most likely to create the fear of missing out that brings buyers back. Matteis warned that investors are reluctant to buy into weakness, saying "the market is not patient" and that the decline could extend another 10% to 15%.
Clinical developments added to the uncertainty. Bristol Myers Squibb reported positive phase 3 data for its LPA1 receptor antagonist in idiopathic pulmonary fibrosis, though the low dose reached statistical significance while the high dose did not. Contineum, which Matteis covers, rose 20% pre-market before closing down more than 25%. Argenx terminated its VivGuard phase 3 in Sjögren's on futility, hours after a bullish panel at a Boston symposium. Arrowhead reported first clinical data for a transferrin-conjugated siRNA showing up to more than 80% tau lowering in CSF, though analysts noted CSF tau may not reflect brain tau burden. Mirum reported positive phase 3 data for Livmarli across pediatric cholestatic diseases, mostly biliary atresia.
IPO activity continues, with roughly 28 biotechs listed in 2026 and on pace for 30 or more, according to the analysts. Verber advised issuers to go public only with a near-term catalyst. Recent offerings included TRex Bio ($117M gross proceeds), Iambic Therapeutics ($150M), and Citi Therapeutics ($200M, upsized). Elektor raised $75 million the morning after an R&D event. In oncology, the Moderna-Merck mRNA cancer vaccine data announced in August 2026 showed a significant progression-free survival benefit in melanoma, though Jake Becraft noted the control was a null placebo rather than a non-antigen-specific mRNA vaccine, which complicates attribution of benefit.
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