IO Biotech: Chapter 7 Liquidation After Phase 3 Trial Misses Endpoint

IO Biotech, Inc., a clinical-stage immuno-oncology company, filed a voluntary chapter 7 petition on March 31, 2026, in the U.S. Bankruptcy Court for the District of Delaware (Case No. 26-10457). All employees and officers were terminated, all six board members resigned, and the company stated it will no longer file SEC periodic reports. The filing follows the FDA's September 2025 recommendation against submitting a Biologics License Application for IO Biotech's lead candidate, Cylembio, after its Phase 3 trial missed statistical significance (p=0.056 vs. required p<=0.045). The company raised over $300 million in cumulative funding, including a $115.1 million IPO in November 2021 at $14.00 per share. IOBT traded at approximately $0.045 on filing day, down 75% on the announcement and 99.7% from its IPO price.

Debtor(s)	IO Biotech, Inc.
Court	U.S. Bankruptcy Court, District of Delaware
Case Number	26-10457
Petition Date	March 31, 2026
Estimated Assets	$1M-$10M
Estimated Liabilities	$10M-$50M
Ticker	IOBT (Nasdaq, expected to be delisted)

Company Background

IO Biotech was founded in December 2014 in Copenhagen, Denmark, as a spin-off of the National Center for Cancer Immune Therapy at Herlev University Hospital. Co-founders Mai-Britt Zocca, PhD (CEO) and Professor Mads Hald Andersen developed the company's T-win technology platform for immune-modulating therapeutic cancer vaccines.

The company raised approximately EUR 44.5 million in a Series A round in 2018 and EUR 127 million in a Series B in January 2021. IO Biotech completed its IPO on November 5, 2021, selling 8,222,500 shares at $14.00 per share for approximately $115.1 million in gross proceeds. Morgan Stanley, Jefferies, and Cowen served as joint lead book-runners. In August 2023, the company raised an additional $75 million through a PIPE private placement.

In December 2024, IO Biotech secured a EUR 57.5 million debt facility from the European Investment Bank (EIB), consisting of three committed tranches (EUR 10 million, EUR 12.5 million, and EUR 15 million) plus a EUR 20 million uncommitted accordion. EUR 22.5 million was drawn before the filing.

The company was headquartered in Copenhagen with a U.S. office in New York.

Lead Candidate and Clinical Failure

IO Biotech's lead candidate, Cylembio (IO102-IO103), was a first-in-class, off-the-shelf therapeutic cancer vaccine targeting IDO1 and PD-L1. The FDA granted Breakthrough Therapy Designation in 2020 for Cylembio in combination with pembrolizumab for advanced melanoma. The company had a clinical collaboration with Merck for pembrolizumab supply.

The pivotal Phase 3 IOB-013/KN-D18 trial enrolled 407 patients across more than 100 sites globally, comparing Cylembio plus pembrolizumab versus pembrolizumab alone in first-line advanced melanoma. Results presented at ESMO 2025 showed median progression-free survival of 19.4 months versus 11.0 months (hazard ratio 0.77), but the result missed the pre-specified statistical significance threshold (p=0.056 vs. required p<=0.045).

Following a pre-BLA meeting in September-October 2025, the FDA advised IO Biotech not to submit a Biologics License Application based on the existing data and recommended a new registrational study.

Financial Deterioration and Cash Burn

IO Biotech did not generate commercial revenue. The company's cash position declined from $211.5 million at year-end 2021 to $30.7 million by September 2025. Annual net losses were $75 million (2021) and $95.5 million (2024), driven primarily by R&D expenses of $71.5 million in fiscal 2024.

As of September 2025, the company reported total assets of $40 million, total liabilities of $39.1 million, and shareholders' equity of $910,000. Long-term debt of $16.7 million reflected the drawn EIB facility. Post-FDA refusal, the company estimated its cash runway extended only through the first quarter of 2026.

The bankruptcy petition reports estimated assets of $1-10 million and liabilities of $10-50 million, reflecting additional months of cash burn and wind-down costs beyond the September 2025 balance sheet.

Wind-Down and Strategic Alternatives

In September 2025, IO Biotech reduced its workforce by approximately 50%, incurring restructuring charges of $1.0-1.5 million. On January 21, 2026, the board initiated a strategic alternatives review to explore merger, business combination, asset sale, or liquidation. Raymond James & Associates was retained as exclusive financial advisor.

On January 28, 2026, Chief Medical Officer Qasim Ahmad, MD was terminated effective February 15, and the company announced further workforce reductions with one-time charges of $2.4-2.6 million. The strategic alternatives process did not produce a buyer, merger partner, or asset purchaser, leading to the chapter 7 filing.

Board Resignations and Terminations

All six directors resigned on March 31, 2026, concurrent with the filing: Peter Hirth (Chairman), Helen Collins, Christian Elling, Kathleen Glaub, Heidi Hunter, and David Smith. The company stated the chapter 7 filing "effectively eliminated the powers of the Company's Board of Directors."

CEO Mai-Britt Zocca, CFO Amy Sullivan, and all remaining employees were terminated without cause on March 31, 2026.

Key Creditors

The European Investment Bank holds the largest identified claim at EUR 22.5 million drawn under the December 2024 facility. The chapter 7 filing triggers an event of default, giving EIB the right to demand immediate repayment plus accrued interest, prepayment fees, and costs. EIB also holds warrants to purchase IOBT common stock.

Shareholder Impact

Major pre-bankruptcy shareholders included Lundbeckfond Invest A/S (~21%), Novo Holdings A/S (~11%), and Vivo Capital (~10%). Institutional holders included Ikarian Capital, Bank of America, Morgan Stanley, Beacon Pointe Advisors, and Renaissance Technologies.

The company stated it is "unlikely that holders of the Company's common stock will receive any payment or other distribution" from the bankruptcy proceedings. IOBT stock declined approximately 75% on filing day to $0.045 per share, down 99.7% from its $14.00 IPO price. The 2025 audit was not completed, and the company stated it will not file future SEC periodic reports.

Professional Retentions

Allison S. Mielke of Young Conaway Stargatt & Taylor, LLP (Wilmington, Delaware) serves as debtor's counsel. Sierra Constellation Partners LLC serves as financial advisor for the bankruptcy. Raymond James & Associates served as financial advisor for the pre-petition strategic alternatives process.

Key Timeline

Frequently Asked Questions

Why did IO Biotech file chapter 7 instead of chapter 11?

The company chose liquidation after its strategic alternatives review did not produce a buyer or merger partner. With its lead drug candidate unable to secure FDA approval, no commercial revenue, and cash runway exhausted, there was no operating business to reorganize.

What happens to the Cylembio clinical data?

A court-appointed chapter 7 trustee will administer the liquidation of IO Biotech's assets, which include its intellectual property, clinical data, FDA designations, and patents. These assets may be sold to other pharmaceutical companies through the liquidation process.

Will shareholders receive anything?

The company stated it is unlikely that common stockholders will receive any payment or distribution from the bankruptcy proceedings. With estimated liabilities of $10-50 million exceeding assets of $1-10 million, creditors have priority over equity holders.

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