1Q26: Ph1 '4071 HV Study Initiated; Ph2 '329 FOS & OL PPR Studies To Start Q2

Research evidence excerpt

1Q26: Ph1 '4071 HV Study Initiated; Ph2 '329 FOS & OL PPR Studies To Start Q2

TD Cowen Ovid Therapeutics

Global Research May 12, 2026

A translational Ph1 HV ketamine challenge crossover study (n=26) of '4071 is planned for a 2H26

start following Ph1 PK characterization. The study will utilize ketamine to transiently induce E/

I imbalance and is designed to assess whether '4071 reverses abnormalities in gamma-band

power, sensory gating, and MMN.

Pending positive Ph1 PK and Ph1 ketamine challenge results, a Ph2 POC '4071 acute

schizophrenia study (n=180) is expected to start in 2H27. The primary endpoint will be change

from baseline in PANSS total score. OVID plans to conduct Ph1b signal finding studies in PDP

and LBD-associated psychosis (n=40) in parallel, with primary endpoints focused on standard

hallucination and delusion rating scales (e.g. SAPS) and MMN explored to confirm target

engagement.

'329 Expands Into TSC Seizures and Infantile Spasms For Ph2: Ph2 Signal Finding Trial For TSC

To Start In 4Q26

OVID also plans to expand the development of '329 into TSC-associated seizures and infantile

spasms (IS) and will advance a pediatric-specific formulation amenable for infant and child use.

While vigabatrin (Sabril) is approved in both indications, its clinical utility is limited by

ophthalmic safety concerns (due to preferential accumulation in the retina). Given '329’s

differentiated safety/tolerability profile and a well-validated GABA-AT inhibition mechanism

conferring clinical benefit in TSC (based on precedent vigabitrin data), OVID believes expansion

into these pediatric indications is meaningfully de-risked.

For TSC-associated seizures, a Phase 2 safety and signal-finding study is expected to initiate in