Fusion Antibodies Cuts Loss by 32% as OptiMAL® Nears Commercial Launch

Half-year numbers: loss narrows, OptiMAL is nearly out of the lab

Fusion Antibodies has posted its unaudited interim results for the six months to 30 September 2025. The headline is straightforward: the loss is narrowing as the Company gears up to launch OptiMAL, its new human antibody discovery platform.

Revenue was £0.84 million, down on H1 FY2025 (£1.2 million) but up on the immediately preceding half (£755k). Gross margin improved to 30% (H1 FY2025: 27%), R&D spend stepped up to £350k, and the loss for the period reduced by 32% to £0.51 million.

Operationally, Fusion secured a US patent for OptiMAL’s library and design method, reported strong validation results with the US National Cancer Institute (NCI), and lined up new work in humanisation and cell line development. The formal commercial launch of OptiMAL is slated for 15-17 December 2025.

Key figures at a glance

Metric	H1 FY2026	Comparator
Revenue	£0.84 million	H1 FY2025: £1.2 million
Gross margin	30%	H1 FY2025: 27%
R&D expenditure	£350k	H1 FY2025: £176k
Loss for the period	£512k	H1 FY2025: £758k
EBITDA loss	£494k	H1 FY2025: £734k
EBITDA loss excluding R&D	£144k	H1 FY2025: £558k
Cash at 30 Sept 2025	£252k	31 Mar 2025: £359k
Debtors owed	£543k	Not disclosed prior
Borrowings	£388k	31 Mar 2025: £20k
Shares in issue	113,656,253	H1 FY2025: 95,365,564

OptiMAL validation: patent granted and real-world performance

This is the strategic pivot. OptiMAL is Fusion’s fully human antibody discovery platform, using a mammalian display system (a way to present antibodies on living mammalian cells so they behave more like they do in humans) and a proprietary Opti-library. The US patent (no. US12378696) now protects the library design and the method for making more libraries. That matters for commercial defensibility.

Validation with the NCI delivered antibody “hits” across three targets, with very high affinity binders in the single digit nM range. In plain English: the platform isn’t just theoretical – it is generating high-quality candidates against both proteins and peptides. Because OptiMAL does not rely on an animal immune response, it can shine where peptide antigens typically underwhelm traditional animal immunisation approaches.

Importantly, NCI wants to keep using OptiMAL and discussions are underway to agree terms. Fusion also highlighted the successful technology transfer to the NCI’s lab, which opens the door to a scalable licensing model. If licensing takes off, margins could be structurally higher than service-only work.

New contracts show the core services still have pull

Alongside OptiMAL, Fusion’s bread-and-butter services continue to land work. There were new contracts for cell line development and two humanisation deals with specialist divisions of large pharma. Humanisation is the process of adapting non-human antibodies to look and behave like human ones, improving the chance of clinical success.

Notably, on 27 August 2025 Fusion won three follow-on projects linked to an existing stable Cell Line Development engagement with a US biotech. That added around $460,000 of extra fees, with a minimum of $400,000 expected to be recognised in the current financial year ending 31 March 2026. The Company also announced a new multi-target Integrated Therapeutic Antibody Services project with a European-based global pharma’s Antibody Centre of Excellence. These are precisely the larger, steadier clients Fusion wants in order to reduce dependence on smaller, more volatile orders.

Why the financials improved despite lower revenue

Two levers drove the better loss profile. First, gross margin edged up to 30%, helped by cost control and improved utilisation. Second, operating discipline shows up in the EBITDA trend: an EBITDA loss of £494k, or just £144k when you strip out the £350k of R&D investment. That R&D spend is deliberate and focused on OptiMAL and grant-backed projects.

There was £370k of other operating income booked. The RNS does not break this out further, but it supported the period’s results. SG&A fell to £807k, £136k lower than the comparable figure reported for H1 FY2024.

Cash, debt and going concern: the key risk to watch

Cash at the period end was £252k, with a further £543k owed by existing debtors. Borrowings rose to £388k after a £400k facility was added during the half, secured against the Company’s assets. Fusion also raised £569k of equity in the period. Net assets stand at £726k.

The Directors have prepared the accounts on a going concern basis, but they flag a material uncertainty. In short: if revenue and cash conversion do not land as forecast, Fusion may need additional funding. Management says the cash position as at 21 November 2025 was better than at the period end, but no absolute figure is disclosed.

My take: the launch of OptiMAL and conversion of the £1 million indicative pipeline will need to translate into signed contracts and cash receipts quickly. The enlarged borrowings provide some flexibility, yet they also raise the stakes on execution.

Strategic extras: grants, markets and patent footprint

Fusion and Queen’s University Belfast won a new grant to co-develop a DR5-targeting antibody aimed at cancer. Total grant funding exceeds £808k, with Fusion expecting up to £545k over roughly 18 months, with the goal of a licensable clinical-ready asset at the end.

Patent coverage is being pursued beyond the US to Europe, China and Japan, which would enhance commercial reach. Management also sees adjacent opportunities in Diagnostics and veterinary markets, and says prospective clients view OptiMAL’s mammalian display as well suited to other libraries, including AI or non-human libraries.

Outlook: what moves the share price next

Fusion expects to launch OptiMAL commercially in mid-December and reports positive pre-launch feedback, with several potential trial users. The Company believes the initial OptiMAL/mammalian display pipeline is worth around £1 million. Alongside that, at least $400,000 from the US biotech cell line programme is expected to be recognised this financial year. Margins have improved year on year, and management expects further efficiency gains.

Against this, underlying revenue growth for the half was down 30% and cash remains tight. The investment case now hinges on rapid conversion of the OptiMAL opportunity, continued big pharma traction in services, and sealing an extended agreement with the NCI.

What I’ll be watching

• OptiMAL launch in December 2025 and the first signed commercial trials or licences.
• Terms and timing of the proposed extended NCI agreement.
• Cash inflows from the £543k debtor book and recognition of at least $400,000 on the US biotech work.
• Gross margin trend as utilisation improves and licensing potentially starts.
• Any further funding steps, given the going concern uncertainty and increased borrowings of £388k.

Bottom line: cautious optimism, execution critical

Fusion has done the hard technical yards: a granted US patent, credible NCI validation, and strong early interest. The financial trajectory is better, with losses narrowing and margins improving despite lower revenue year on year. However, the balance sheet is finely poised and the auditors flag a material uncertainty around going concern if forecasts slip.

If OptiMAL lands its early customers and an NCI extension, a scalable licensing layer could sit atop the services business and lift long-term value. Until then, this remains a high-potential but execution-sensitive story.