SVN-015 Advances into Further NIDA-Funded Studies Following Encouraging

Solvonis Therapeutics plc (LSE: SVNS), a late clinical-stage biopharmaceutical company developing novel small-molecule therapeutics for high-burden central nervous system (“CNS”) disorders, is pleased to announce encouraging results from the initial in vitro cardiac ion-channel and broader off-target screening of SVN-015 under the U.S. National Institute on Drug Abuse’s (“NIDA”) Addiction Treatment Discovery Program (“ATDP”). The Company previously announced SVN-015’s acceptance into the ATDP in December 2025.

Following review of the initial screening results, NIDA has confirmed that SVN-015 will advance into further evaluation under the ATDP. This is expected to include confirmatory transporter studies and in vivo studies to characterise the onset and duration of its pharmacological activity.

SVN-015 is a proprietary discovery-stage small molecule designed to modulate key monoamine transporters, including the dopamine transporter (“DAT”) and serotonin transporter (“SERT”). It is being developed initially as a potential treatment for stimulant use disorder, including cocaine and methamphetamine use disorders.

Encouraging Initial Screening Results

The initial NIDA evaluation was designed to identify potential cardiac ion-channel and broader off-target liabilities before SVN-015 progressed into more extensive preclinical pharmacological studies.

SVN-015 completed the initial cardiac ion-channel screening and demonstrated an encouraging broader off-target profile. The results were sufficiently encouraging for NIDA to progress the compound into further evaluation.

On the cardiac ion-channel measures assessed to date, SVN-015 demonstrated a more favourable profile than GBR-12909, an earlier dopamine transporter inhibitor evaluated by NIDA as a potential treatment for cocaine dependence and known to interact with several cardiac ion channels.

These preliminary preclinical findings do not establish the safety of SVN-015 in humans or whole animals. Further safety pharmacology, toxicology and clinical evaluation will be required as the programme progresses.

Advancement into Further Preclinical Evaluation

The next stage of the NIDA programme is expected to further characterise SVN-015’s intended transporter pharmacology, off-target profile and activity in vivo.

The planned work is expected to include:

• in vivo mouse locomotor-activity time-course study to characterise the onset and duration of SVN-015’s pharmacological effects
• confirmatory DAT binding and functional studies;
• follow-up assessment of activity at the 5-HT2B receptor.

These studies will be funded and undertaken through NIDA’s preclinical ATDP. This support provides Solvonis with access to NIDA-funded specialist research capabilities rather than a grant payment to the Company. Solvonis retains ownership of SVN-015 and its associated intellectual property.

Successful completion of this stage would provide Solvonis with an important preclinical data package to inform the compound’s future development…