Announces Positive Bridging Data Supporting

LONDON - 22 June 2026 - Solvonis Therapeutics plc (LSE: SVNS), a late clinical-stage biopharmaceutical company developing novel small-molecule therapeutics for high-burden central nervous system ("CNS") disorders, announces positive pharmacokinetic ("PK") data from the preclinical bridging study for its SVN-002 development programme.

SVN-002 is Solvonis' proprietary esketamine oral thin-film ("OTF") formulation being developed for moderate-to-severe Alcohol Use Disorder ("AUD") in the United States. It is designed for supervised, clinic-administered sublingual-buccal dosing. The programme also incorporates a structured alcohol education component, intended for future remote digital access by patients. The programme is being advanced under a planned U.S. Food and Drug Administration ("FDA") 505(b)(2) regulatory pathway referencing the FDA-approved intranasal esketamine product, Spravato®.

Key Study Results and Regulatory Alignment

The nonclinical study was designed to assess whether the intended combined sublingual-buccal administration of SVN-002 could generate systemic esketamine exposure supportive of a scientific bridge to the approved intranasal esketamine reference product.

The results were positive.

At the same nominal dose level, combined sublingual-buccal administration of SVN-002 produced rapid systemic exposure to parent esketamine. Exposure levels for parent esketamine and the key measured metabolites, noresketamine and hydroxynoresketamine, were within the range observed for the intranasal esketamine comparator arm, providing important translational support for the planned scientific bridge.

At the December 2024 Type B pre-IND meeting held with the FDA by Awakn Life Sciences, prior to the asset's acquisition by Solvonis, FDA identified systemic exposure to esketamine and relevant metabolite exposure as key considerations for the initial Investigational New Drug ("IND") package.

Solvonis believes these newly generated data provide important translational support in relation to the FDA-identified exposure considerations and strengthen the planned initial IND package for SVN-002.

Next Steps

Following these positive results, Solvonis will seek further FDA feedback on the scope and scale of the remaining nonclinical toxicology work required for the initial IND submission.

Subject to FDA feedback and successful completion of this targeted toxicology package, Solvonis plans to submit an IND to support the initiation of a Phase 2b clinical trial of SVN-002 in patients with moderate-to-severe AUD in the United States.

Commercial Context and the 505(b)(2) Advantage

AUD represents a major and underserved U.S. market opportunity characterised by limited pharmacological innovation. According to the 2024 U.S. National Survey on Drug Use and Health, approximately 27.9 million people aged 12 and older in the U.S. had Alcohol Use Disorder in the past year. Solvonis estimates that approximately 15 million U.S. adults fall within the programme's target moderate-to-severe AUD population.

Spravato® provides a relevant commercial reference point for supervised, clinic-administered esketamine treatment models. Johnson & Johnson reported worldwide Spravato® sales of approximately US$1.7 billion in 2025 for depression-related indications. Solvonis estimates that SVN-002's target U.S. moderate-to-severe AUD population is approximately five times larger than the estimated U.S. treatment-resistant depression comparator population of approximately 2.8 million people.

The planned 505(b)(2) pathway is central to the capital efficiency of the SVN-002 development strategy. A successful 505(b)(2) route may allow Solvonis to rely, in part, on the FDA's prior findings of safety and/or effectiveness for the approved intranasal esketamine reference product, provided a suitable scientific bridge is established. Solvonis intends to build the SVN-002 package using existing third-party preclinical data, in-licensed Phase 1 clinical data, and targeted SVN-002 bridging and toxicology studies, rather than duplicating a full conventional de novo development package. The Company believes this approach has the potential to reduce development expenditure and support a more capital-efficient route towards Phase 2b.

Anthony Tennyson, Chief Executive Officer of Solvonis Therapeutics, said: "This is an important technical and regulatory milestone for SVN-002.

"The study was designed to test whether our intended combined sublingual-buccal delivery could generate esketamine exposure supportive of a scientific bridge to the approved intranasal esketamine reference product. The data support that objective and provide an important basis for the next stage of regulatory engagement, including FDA feedback on the remaining toxicology package.

"SVN-002 targets a large and poorly served U.S. Alcohol Use Disorder market through a differentiated thin-film product and a planned capital-efficient 505(b)(2) regulatory pathway. Subject to successful completion of the required toxicology work, our plan is to submit an IND to support a Phase 2b trial in moderate-to-severe AUD."

Professor David Nutt, Chief Scientific Officer of Solvonis Therapeutics, added: "The pharmacokinetic profile observed in this study is very encouraging. Combined sublingual-buccal administration produced rapid systemic exposure to parent esketamine and supports the core rationale for SVN-002 as a transmucosal thin-film product.

"These results provide important translational evidence for our planned U.S. regulatory pathway and support SVN-002's continued development as a supervised, clinic-administered treatment candidate for AUD."