NCT07439510

A Study to Investigate the Effects and Safety of SPG601 for the Treatment of Fragile X Syndrome in Male Participants

A Phase 2b/3, Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy, Safety, and Pharmacokinetics of SPG601 in Male Participants With Fragile X Syndrome

• Status: Not Yet Recruiting
• Phase: Phase 2 / Phase 3
• Study type: Interventional
• Enrollment: 248 (estimated)
• Sponsor: Spinogenix · Industry
• Sex: Male
• Age: 18 Years – 45 Years
• Healthy volunteers: Not accepted

Summary

This Phase 2b/3, randomized, double-blind, placebo-controlled, 2-part study will evaluate the efficacy, safety and tolerability of different dose regimens of SPG601 in adult male participants with Fragile X syndrome.

Detailed description

This is a Phase 2b/3, randomized, double-blind, placebo-controlled, study designed to evaluate the efficacy, safety and tolerability of multiple dose regimens of SPG601 in male participants with FXS. The study consists of two parts, Phase 2b, dose-regimen finding, 4-arm parallel design: Eligible participants will be randomized to receive SPG601 or matched placebo. Participants will receive study intervention over 4 weeks and will be followed up for 4 weeks after last dose of study intervention. Phase 3, 2-arm parallel design: Eligible participants will be randomized 1:1 to receive SPG601 or matched placebo. The dose of SPG601 administered in the Phase 3 will be defined based on analysis of Phase 2b. Participants will receive study intervention over 12 weeks and will be followed up for 4 weeks after last dose of study intervention.

Conditions

• Fragile X Syndrome (FXS)

Interventions

Type	Name	Description
DRUG	SPG601	synthetic small molecule
DRUG	Placebo	Placebo

Timeline

• Start date: 2026-03-01
• Primary completion: 2030-02-01
• Completion: 2030-06-30
• First posted: 2026-02-27
• Last updated: 2026-02-27

Regulatory

• FDA-regulated drug study