aibioNorthwest Biotherapeutics says 10-K is late over Advent BioServices accounting
Tickers NWBO
The company cites issues tied to its Advent BioServices acquisition, including differences between UK GAAP and US GAAP. The notice gives no date for the annual report.
Key facts
- Company
- Northwest Biotherapeutics, Inc. (OTC: NWBO)
- News type
- Distress
- Primary source
- Northwest Biotherapeutics, Inc. NT 10-K (2026-03-31)
Northwest Biotherapeutics, Inc. said on March 31, 2026 that it cannot file its annual report on Form 10-K for the year ended December 31, 2025 on time. The same day it filed a notice of late filing on Form 12b-25. For an annual report, that notice gives the company until the fifteenth calendar day after the normal due date.
What the notice says
The notice is signed by Linda F. Powers as chief executive officer and chairman. It says the company "is unable, without unreasonable effort or expense, to file its Annual Report on Form 10-K" within the prescribed period. It blames "complex issues related to the Company's acquisition of Advent BioServices" that came up in the final stages of preparing the report. It cites differences between UK GAAP and US GAAP as part of the problem.
The notice does not say what those issues are, how large they are, or which reported figures they could change. It also answers no when asked whether it expects a significant change in results of operations from the prior year. The notice contains no results figures, so that answer cannot be tested against anything in the filing.
The company says it is working to file the report as soon as it reasonably can, but it gives no date. It names the timing of the interim review and audits by its independent registered public accounting firm as the factor that could change that timing.
The Advent question
The notice does not give the date, price or terms of the acquisition it describes. The business section of the company's 2024 annual report, filed March 31, 2025, calls Advent BioServices the company's contract manufacturer and the contract operator of the Sawston facility in the United Kingdom. The notice leaves open when the company took control of Advent and what it paid.
Sawston is central to the company's manufacturing plans. The 2024 report puts the facility's anticipated potential capacity at about 40 to 45 patients a month, or approximately 450 to 500 patients a year. Those are capacity figures, not output, and the 2024 report gives no production record. The company also sub-leased part of the building to Advent on December 31, 2021. It tied that step to an obligation under a buildout loan from the Cambridge development authority, which requires the facility to benefit the regional business ecosystem and not only the company.
The therapy and the approval path
The lead candidate, DCVax-L, uses a patient's own dendritic cells, loaded with antigens from that patient's tumor. The company says it completed a 331-patient international Phase III trial in glioblastoma, a brain cancer, and published the results in JAMA Oncology. It submitted a Marketing Authorization Application in the United Kingdom on December 20, 2023. Neither the notice nor the 2024 report reports a decision on that application.
That is one Phase III trial in one cancer. The company plans trials of DCVax-L in other solid tumors only when resources permit. The second candidate, DCVax-Direct, has completed a 40-patient Phase I trial that covered more than a dozen cancer types. The 2024 report gives no efficacy results from that trial, and preparations for a Phase II trial go forward only as resources permit.
The company calls its Flaskworks closed manufacturing system central to scaling up. Once the GMP-grade units are delivered, Advent is to qualify and validate them, run engineering tests and apply to regulators for approval to use the system to make DCVax-L for patients. Those steps are still ahead. The company expects batch manufacturing to put DCVax pricing in line with other new cancer drugs, but the 2024 report gives no price or cost figure to support that expectation.
As of December 31, 2024, the company held 48 issued patents and had 60 pending patent applications worldwide.
What comes next
The notice commits to no filing date for the 2025 annual report. It gives no figures for the 2025 year, and no cash, loss or financing details. A reader of this notice alone cannot judge the company's financial position, or how long the delay could last against the funds it has.