Takeaways From Our NYC Investor Meetings

Research evidence excerpt

Takeaways From Our NYC Investor Meetings

C O M PA N Y N O T E

J u n e 1 7 , 2 0 2 6

Topic #4: Ulixacaltamide Ph3 Essential3 interim refresher for new investors

1. For investors new to the PRAX story, mgmt provided an overview of ulixacaltamide's Essential

Tremor (ET) development path. Specifically, in February 2025 PRAX announced the IDMC

determined Ph3 Essential3 (NCT06087276) Study 1 as futile, where mgmt decided to complete

both Study 1 (placebo-controlled) and Study 2 (randomized withdrawal) given capital was already

allocated and enrollment was almost complete (note here). Additionally, mgmt reminded us Study

2 was intrinsically linked to Study 1 where de-coupling the trials would not be beneficial to the

overall program. See pgs. 7-8

2. With this, mgmt also walked through the changes to Essential3 which were mainly related to

changing the Study 1 primary endpoint to Day 56 (vs Day 84) and incorporation of the ability

to test two additional hypotheses (note here). Further, mgmt reminded investors that advisors

detailed changing the time point of the primary endpoint in Study 1 was a small change where

the protocol was efficiently amended and submitted to the FDA with a finalized statistical plan.

Of course, it is crucial to appreciate Essential3 Study 1 ended up successful at both the Day 56

and Day 84 timepoints (note here) where the FDA was very involved throughout the Essential3

program. See pg. 8

3. Moreover, new investors did not realize PRAX presented a comprehensive data package to the

agency during their ulixacaltamide pre-NDA meeting in December 2025 (note here). Importantly,

mgmt expressed this made sense considering ulixacaltamide is potentially the first drug to be

approved on an ET development plan. With this, the agency did not want PRAX to do any