PIPELINE

SOM3355 is a molecule with an innovative Mechanism of Action (MoA) being a selective β-adrenergic blocker and a VMAT1 and VMAT2 inhibitor. It is a different class of drugs for the treatment of Huntington's Disease and potentially the only drug to address the complex symptomatology beyond chorea over the different stages.

The β-blocking activity is known to underly improvement of behavioral symptoms, akathisia and anxiety, and prevents imbalance of dopamine and β-adrenergic systems interactions due to dopamine inhibition associated with VMAT1 and VMAT2 inhibition.
The modulation of dopamine through VMAT1 expressed in pre- and frontal cortex and in other areas, like the nucleus accumbens and VMAT2 inhibition, in the basal ganglia, particularly the striatum leads to improvement of chorea without causing or exacerbating HD symptoms.
This MoA is unique to SOM3355 and not ascribed as a β-blockers class effect.

SOM3355 successfully completed a Proof of Concept clinical study and a Phase 2b clinical study on Huntington’s patients with chorea showing efficacy with no sign of worsening depression, somnolence, anxiety and akathisia.

SOM3355 recently obtained a positive opinion from EMA COMP based on the clinically significant benefit criteria, for the treatment of Huntington beyond chorea.
SOM3355 has already an Orphan Drug Designation granted in the US.

The End of Phase2 meeting with FDA held in Sept 2025 yielded an understanding on the path forward into a Phase 3 and NDA filing.

The Company plans to progress with a Phase3 study in Huntington Disease and to develop the drug also for other indications among which Tardive Dyskinesia.

Huntington's Disease (HD) is a genetic rare progressive neurodegenerative disease characterized by motor, cognitive and psychiatric abnormalities. Chorea is a key symptom of HD and occurs in approximately 90% of HD patients characterized by abnormal, jerky, muscular movements of extremities, facial and axial muscles compromising the daily living. Psychiatric disturbances, behavioral difficulties and cognitive decline emerge and evolve over time.

SOM3366 is R-enantiomer of SOM3355 with less effect on the β1-adrenoceptor, and it is a New Molecular Entity. SOM3366 is under evaluation for the treatment of Tourette Syndrome, a movement and neuropsychiatric disorder, as first indication and it may be expanded to other movement disorders. FDA guidance (pre-IND meeting) and EMA Scientific Advice were obtained.

SOM1311 is a small molecule chaperone of Phenylalanine Hydroxylase under development for the treatment of Phenylketonuria. The molecule showed promising preclinical data that supports moving directly to a Phase 2a PoC.

Phenylketonuria (PKU) is characterized by a birth defect that causes the amino acid, phenylalanine to build up in the body. Untreated, PKU can lead to intellectual disability, seizures, behavioral problems, and mental disorders.