Key Ox-1 milestone & notice of investor webinar

Manufacturing of drug substance successfully scaled up to supply 28-day toxicology studies

Alderley Park, 5 January 2026 - TheraCryf plc (AIM: TCF), the clinical stage drug development company focussing on brain disorders, has started 2026 positively, achieving a key milestone on the path to clinical readiness for its Ox-1 orexin blocker potential treatment for addictive disorders.

• Process for large-scale manufacturing of drug substance established
• Scale-up achieved on schedule with a manufacturing yield in excess of target
• 10.6kg produced to supply critical 28-day regulatory toxicology studies
• Dosing in two species has now commenced to identify maximum tolerated dose for 28-day regulatory toxicology studies
• These studies will begin in Q1/2 2026, depending on species
• All studies on schedule to complete Q3 2026

Manufacturing scale-up and completion of 28-day toxicology studies were highlighted, during the successful placing in March 2025, as the two key milestones remaining in the Ox-1 programme to achieve clinical readiness. Scale-up of the Ox-1 compound to 10kg has now been achieved on schedule and with a yield in excess of expectations.

This drug substance will be used in the 28-day regulatory toxicology studies scheduled to commence, in Q1 and Q2, this year in two species. These studies will provide essential data for the planned regulatory submission later in the year and represent the last major hurdle to achieving that goal.

Before starting the 28-day toxicology studies, the Maximum Tolerated Dose and Dose Range Finding studies need to be completed. This work has now started. These studies will identify the 'therapeutic index' of the orexin-1 blocker - that is the range between which the dose is expected to have a therapeutic effect and the highest dose of compound reached before any harmful effects are observed.

Ox-1 is TheraCryf's lead asset, an orexin-1 blocker, being developed as a potential treatment for addiction, blocks a pathway in the brain (orexin-1) known to be over-active in individuals with addiction. This group of conditions have significant human and economic impact globally. Blocking the overactivity of this pathway is known to reduce aberrant substance seeking behaviour in animal models. Drugs that can block this pathway have generated significant commercial interest and Theracryf's orexin-1 blocker is the most selective yet developed, indicating class leading potential.

Investor Webinar

Dr Huw Jones, Chief Executive Officer, and Dr Alastair Smith, Non-executive Chair, will be presenting a webinar hosted by TheraCryf's joint broker, Turner Pope Investments, at 6:00p.m. on Thursday, 8 January 2026.

The webinar will look at the progress made by TheraCryf in 2025 in driving its lead Ox-1 orexin blocker programme towards clinical trial readiness and also the potential milestones and value inflection points for TheraCryf coming up in 2026, including manufacturing scale-up as described above. A Q&A session will follow the main presentation.

The webinar is freely available for all existing and potential investors. To register for the event and submit questions, please go to: https://www.turnerpope.com/register/

Dr Helen Kuhlman, COO of TheraCryf commented:

"We are pleased to have achieved this key milestone in the development of our potentially class leading orexin blocker programme, on schedule. These activities are critical to generating a robust data package to enable human trials and we are on track to deliver them during 2026."