PT320 slow-release exenatide

The research record

This is the project's file for this landmark, as written and checked. Sources are listed at the end; anything not yet confirmed is marked "Not yet verified".

Who

Peptron, Inc. (South Korea), at five Seoul hospitals: Seoul National University Hospital, SNU Bundang, SNU Boramae, Asan Medical Center and Samsung Medical Center.

What happened

Exenatide is a diabetes drug that mimics the gut hormone GLP-1. The 2013 pilot (landmark 101) suggested benefit, but the weekly form tested in Phase 3 failed (landmark 142). Peptron says PT320, a sustained-release form given weekly or every two weeks, reaches the brain better and is easier to take. Mouse studies, with some authors outside the company, reported protection of mitochondria and dopamine neurons in the MitoPark mouse model (J Biomed Sci 2024) and less levodopa-induced dyskinesia in a mouse model (title only checked).

The trial (NCT04269642, Phase 2a) is randomised, double-blind and placebo-controlled in people aged 40 to 75 diagnosed within 24 months (Hoehn and Yahr 2.5 or less). Planned size is 99. Arms: PT320 2.0 mg weekly, PT320 2.5 mg every two weeks (injected alternately with placebo each week), or placebo, for 48 weeks, by subcutaneous injection. The main measure is change in off-state motor score (MDS-UPDRS Part 3) at 48 weeks. Secondary measures include dopamine-transporter PET (SNBR) and cognition. It started 19 March 2020. The record was last updated 12 April 2021. Its last known status was "active, not recruiting", so recruitment had closed by then; the overall status is now "unknown", estimated primary completion September 2021 and finish December 2021, and no results are posted. The size of 99 is the registry's estimate (it was never revised to an actual count).

Why it moved us toward a cure

It is one of the few GLP-1 follow-ups designed to answer whether a better-penetrating exenatide does what the standard one did not. Without a result it moves nothing yet.

Outcome

Open, with no result. A web search (19 Oct 2026) found no topline data, and a 2022-era Korean news item that I could not verify gave a size of 100 and an expected finish of April 2022.

Sources

• ClinicalTrials.gov NCT04269642 (API re-read 22 Oct 2026: status "unknown", last update 12 Apr 2021, five Korean sites, no results)
• Wang et al., J Biomed Sci 2024, DOI 10.1186/s12929-024-01025-6 (PT320 in MitoPark mice; abstract read, PMID 38627765)
• PT320 and levodopa-induced dyskinesia in a mouse model (title only)
• Not yet verified: whether the trial finished or enrolled fully; any topline data from Peptron; the exact PT320 formulation; the claim of better brain penetration (a sponsor statement).