21 September 2026

Coiled Therapeutics plc

("Coiled Therapeutics" or the "Company")

Successful Enrolment Completed Across Two Cohorts of New AO-252 Formulation

Clinical development advances with enrolment across 120mg BID and 160mg QD cohorts

Coiled Therapeutics (AIM: COIL) (OTCQB: COTXF), the clinical-stage precision oncology company developing differentiated small molecule therapies for genetically defined cancers, provides an update on the clinical development of its next-generation, lipid-based formulation of AO-252, its first-in-class, brain-penetrant small molecule inhibitor of TACC3. Following the dosing of the first patient with the new formulation, announced on 3 August 2026, the Company has successfully enrolled patients across two distinct escalation cohorts: a twice-daily ("BID") 120mg cohort (n=3) and a once-daily ("QD") 160mg cohort (n=3). All patients are progressing as planned through the assessment period, in accordance with the study protocol.

Key Highlights

•   Patients successfully enrolled across two initial cohorts (120mg BID, n=3; 160mg QD, n=3) evaluating the new lipid-based softgel formulation of AO-252.

•   All patients are progressing through the protocol-specified assessment period in the ongoing Phase I study (NCT06136884).

•   The new softgel formulation is designed to achieve more consistent, dose-proportional absorption, building on the 80% Clinical Benefit Rate (CBR) signal observed in earlier twice-daily tablet dosing (n=5).

•   The Company remains confident of dosing up to 30 patients with the new formulation by the end of 2026, as the trial advances towards Phase I/II planned dose-expansion cohorts in ovarian and prostate cancer.

The 120mg BID and 160mg QD dose levels were selected to optimise systemic drug exposure based on encouraging clinical activity observed with the original tablet formulation. As previously announced, the tablet formulation demonstrated an 80% Clinical Benefit Rate ("CBR") in patients receiving twice-daily dosing (n=5), compared with 40% in patients receiving once-daily dosing (n=5). The new pre-dissolved, lipid-based softgel system was specifically designed to reduce absorption variability, enhance bioavailability and deliver a more predictable, dose-proportional exposure, supporting evaluation of AO-252 at sustained dose levels.

Enrolment across these cohorts marks continued progress towards the Company's planned Phase I/II dose-expansion cohorts in ovarian and prostate cancer, with an enrolment target of up to 30 patients with the new formulation by the end of 2026. The Company continues to expect initial safety and pharmacokinetic ("PK") data readouts by the end of 2026, in line with its previously stated development roadmap.

Sridhar Vempati, Chief Executive Officer of Coiled Therapeutics, commented:

"We have now enrolled patients across both our 120mg BID and 160mg QD cohorts with the new formulation, and they are progressing well through their assessment period in line with protocol.  The new formulation was specifically designed to enhance bioavailability and deliver more consistent drug exposure, building on the encouraging 80% clinical benefit rate signal we observed with twice-daily dosing in earlier cohorts.  This is an important step in de-risking our dose-escalation strategy and keeps us firmly on track to dose up to 30 patients by the end of the year, as we advance towards our planned expansion cohorts in ovarian and prostate cancer."

Regulatory Information

This Announcement contains inside information for the purposes of the UK version of the market abuse regulation (EU No. 596/2014) as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018 ("UK MAR").

Forward-Looking Statements

This Announcement contains statements that are, or may be deemed to be, "forward-looking statements". These forward-looking statements can be identified by the use of forward-looking terminology, including the terms "believes", "estimates", "anticipates", "expects", "intends", "may", "will", "plans", "continue" or "should" or, in each case, their negative or other variations or comparable terminology, or by discussions of strategy, plans, objectives, goals, future events or intentions. These forward-looking statements include all matters that are not historical facts. They appear in a number of places throughout this Announcement and include statements regarding the Company's intentions, beliefs or current expectations concerning, among other things, the Company's results of operations, financial condition, liquidity, prospects, growth, strategies, and the industry in which the Company operates.

By their nature, forward-looking statements involve risk and uncertainty because they relate to future events and circumstances that may or may not occur, and are based on current expectations, projections and assumptions about future events, many of which are outside the control of the Company. Forward-looking statements are not guarantees of future performance and the actual results of the Company's operations, and the development of the markets and the industry in which the Company operates, may differ materially from those described in, or suggested by, the forward-looking statements contained in this announcement. In addition, even if the results of operations, financial condition and the development of the markets and the industry in which the Company operates are consistent with the forward-looking statements contained in this announcement, those results or developments may not be indicative of results or developments in future periods.

No representation or warranty is made that any of these forward-looking statements or forecasts will come to pass or that any forecast results will be achieved. Forward-looking statements speak only as of the date of this Announcement and the Company, its directors, officers, employees, agents and advisers expressly disclaim any obligation or undertaking to disseminate any updates or revisions to any forward-looking statements contained herein to reflect any change in expectations or any change in events, conditions or circumstances on which any such statements are based unless required to do so by applicable law or the AIM Rules for Companies.

-Ends-

Enquiries:

About Coiled Therapeutics plc

Coiled Therapeutics (AIM: COIL) (OTCQB: COTXF) is an AIM-listed, clinical-stage precision oncology company advancing first-in-class small molecule therapies targeting validated cancer dependencies. Its lead programme, AO-252, is a novel TACC3 inhibitor currently being evaluated in a Phase I clinical trial in the U.S. (ClinicalTrials.gov ID: NCT06136884). The Company's clinical development strategy is designed to generate the clinical evidence sought by potential pharmaceutical partners in selected tumour types, including ovarian and prostate cancer, while advancing a broader pipeline that includes a STAT6 siRNA programme for immunology indications.

About AO-252

AO-252 is a first-in-class, orally administered, brain-penetrant small molecule designed to selectively inhibit Transforming Acidic Coiled-Coil containing protein 3 (TACC3). TACC3 has emerged as a validated cancer dependency across multiple aggressive solid tumours and is largely dispensable in normal adult cells, supporting the potential for a broad therapeutic window.

By disrupting TACC3-driven protein interactions, AO-252 induces mitotic and replication stress, impairs DNA damage repair and promotes cancer cell death. Its ability to cross the blood-brain barrier is a key differentiator, supporting its potential to treat both primary brain tumours and brain metastases.

AO-252 is currently being evaluated in an ongoing Phase I open-label dose-escalation study. The Company plans to initiate Phase I/II dose-expansion cohorts in ovarian and prostate cancer in H2 2026.

For more information, please visit: www.coiledplc.com and follow us on LinkedIn.