26 Biotech IPOs, but the Float Doesn't Arrive Until April 2027

Almost every corner of the 2026 market is closed. In September, OpenAI ruled out an offering this year; data-center names Airtrunk, Firmus and SB Energy pulled or delayed their filings; smart-ring maker Oura, insurer Bamboo and nuclear operator Holtec International put their listings on hold; and Nscale was pressed by investors to cut its valuation by at least 36%. Biotechnology is the one sector that kept printing: 26 companies debuted on U.S. exchanges this year, more than doubling 2025's tally to the highest count since 2021. Since August 1, 11 of the 16 U.S. offerings that priced have been biotech.

Whichever definition you use, the direction is not in dispute, and neither is the concentration: the general window is shut, and the sector with the longest funding runway and the fewest revenue deadlines is the one still able to sell paper. That is the opposite of a window driven by investor appetite, and it is the first clue that this is a private-market liquidity event wearing a public-market wrapper. It is also why biotech is not the same as easy: in biopharma, 23 reverse mergers matched 23 IPOs this year, and the alternative route to a listing ran wide open even as the IPO route narrowed.

The demand read is two-tier. The head of the book was upsized or priced above range: Parabilis Medicines priced at $20.00, above its range, and closed the offering with full exercise of the underwriters' option for $770.5 million in gross proceeds, plus about $75 million from a concurrent private placement with Regeneron Pharmaceuticals; Braveheart Bio priced at $18.00, a dollar above the top of its range; Latigo Biotherapeutics raised $345.6 million at $18.00; Electra Therapeutics raised $350.0 million at $15.00. The tail did not get that deal: TRex Bio priced at the low end of its range for $117 million, and Retension Pharmaceuticals raised roughly $34 million.

Read the table as two populations wearing one calendar. The record and near-record listings carry real assets: Latigo Biotherapeutics has a non-opioid pain candidate that beat Vicodin head to head in a mid-stage trial, and Kailera Therapeutics reported positive Phase 3 topline data in July for the Hengrui-originated oral agonist HRS-7535. The October tail has neither a differentiated readout nor a large balance sheet, and two of its four names already trade below their offer price. The window is producing real companies at the top and paper at the bottom.

This is not the usual window-dressing pattern, and that distinction matters for how the wave should be priced. In the deals documented this year the stock sold is primary: City Therapeutics issued 11,111,111 new shares, Kailera Therapeutics sold 39,062,500, and Bambusa Therapeutics is offering 9,375,000. Selling shareholders are not the counterparty. The wave routes primary capital into the companies rather than into the pockets of existing owners, which is why it is a genuine funding event and why it cannot deliver a public-market payoff before 2027.

For the buyer of a share, the arithmetic is blunt. Count short- and long-term investments as cash and Kailera Therapeutics's $1.17 billion cash and investments is 67% of its $1.74 billion market value, leaving roughly $580 million of enterprise value for a Phase 3 obesity franchise. At Parabilis Medicines, $1.12 billion of cash and short-term investments cover a third of the $3.44 billion market value, an enterprise value of about $2.4 billion for a company that has booked almost no revenue. A buyer at the IPO was underwriting an option on science with a cash cushion, and the cushion is now the majority of the price.

Two documents make the cliff precise. Bambusa Therapeutics' amended registration statement says the lock-up and market standoff run 180 days from the prospectus date, that only the 9,375,000 shares sold in the offering are freely tradable immediately, and that 39,750,360 additional shares become eligible for sale once those restrictions lapse, 32,568,026 of them held by directors, executive officers and other affiliates and therefore subject to Rule 144 volume limits. Retension Pharmaceuticals's registration statement puts the same structure in miniature: up to 4,582,047 shares eligible for sale after the lock-ups expire, against 8,331,600 shares outstanding. The prospectus puts 79.9% of the share count into the market 180 days after pricing.

The sequence is mechanical. Float expands from roughly a fifth of the shares to nearly four-fifths inside two quarters of 2027, into a buyer base that in 2026 was mostly specialist crossover funds with small positions: Iambic Therapeutics floated about 9.4 million of 47.4 million shares, TRex Bio 8.3 million of 27.4 million, Lycia Therapeutics 7.8 million of 52.1 million. Two of those three are worth about twice the cash their own offerings raised, so the marginal buyer today is paying roughly twice the money for science. That is what a cliff looks like before it arrives.

Kailera Therapeutics is the cleanest case study available, because it is the largest 2026 biotech listing whose lock-up has already lapsed. It priced at $16.00 in April, raising $625 million and then the largest offering ever by a drug developer, and closed its debut day at $26.00, 62.5% above the offer. On July 7 it reported positive Phase 3 topline data from two Hengrui-run trials of the oral agonist HRS-7535, with mean weight loss of up to 11.1% at Week 50. The market read the tolerability profile instead: roughly 70% of patients reported nausea and the shares fell about 10% in a session. Six months after the debut, the stock trades 16% below its $16.00 offer price, 48% below the debut close and more than half off its $28.23 high.

The balance sheet explains why the market is not panicking and the share price is still falling. Kailera Therapeutics spent $121.4 million of operating expenses in the June quarter against zero revenue, and it carried $992.6 million of other non-current liabilities at March 31 that the April listing converted into equity. After the deal, cash and investments stand at $1.17 billion, total liabilities at $93.0 million and equity at $1.12 billion. The market now values a Phase 3 obesity franchise at roughly $580 million of enterprise value, with the original licensor's milestones still ahead of shareholders and the tolerability question still unanswered in a head-to-head sense.

A review of the 75 biotech companies that went public in the U.S. in 2020 gives the honest base rate: only 16% are still above their offer price, 44% are down 90% or more, and an equally weighted portfolio of the group would be down more than 25%. The tail is not hypothetical. Athira Pharmaceuticals, now LeonaBio, is 97% below its IPO price, and Codiak Biosciences filed for bankruptcy protection in March 2023, less than three years after listing. The 2020 cohort left only 16% of its members above the offer price, and the median outcome was a total loss of most of the capital.

The exception shows how wide the distribution is. Revolution Medicines raised about $273 million in its February 2020 IPO and is up roughly 1,000%, after a later raise, a royalty-pharma commitment and an August approval in pancreatic cancer. One outlier is not a cohort. The timing matters too: the 2020 lock-ups expired through 2021, yet Codiak did not go under until 2023, and LeonaBio kept bleeding long after its own restrictions lifted. The lock-up accelerates the pressure rather than creating the loss, which is precisely why the April 2027 calendar is a supply event and not a valuation event.

This is where the bulls point, and the data is genuinely good for them. XBI rose 29.6% in 2026 against 14.7% for the Nasdaq and 10.9% for the S&P 500, and IBB is up 35% after a 28% gain in 2025. But the shape of the year matters more than its endpoint: XBI was down less than 1% in the third quarter, clinical-stage names fell 11% in the same quarter, and the index's five-year high in August has not been regained. The headline index return was carried by large caps while the newly listed clinical cohort fell 11% in the third quarter.

Read the chain end to end and the asymmetry is stark. Banks collect fees on a window whose payoff lands in 2027. Hengrui collects a $100.0 million upfront now and milestones later, and it is paid twice over when Novo Nordisk writes a $2.6 million cheque for a second Hengrui asset, with $300 million upfront. Charles River books the research spend. Novo Nordisk, Eli Lilly and Pfizer pay real money for developed assets. The public shareholder is the only participant in the chain waiting on a price that no lock-up expiry has yet tested.

The 2026 biotech IPO wave is not window-dressing in the cynical sense: the money goes into companies, and two of the three largest listings are genuine assets from Jiangsu Hengrui Medicine with late-stage data. It is something more useful to understand. It is a private-market liquidity event that happens to have a public-market wrapper. The cash arrives, the science gets funded, the banks and the originators get paid, the index gets its exposure, and then the share count locked today becomes sellable between December 2026 and April 2027 into a buyer base that has never seen it offered.