Design Therapeutics (DSGN) investor relations material

Platform overview and clinical progress

• Developing small molecule genomic medicines that target specific DNA sequences to modulate gene expression in monogenic diseases.

• Achieved first clinical proof-of-concept data in Friedreich's ataxia, enabling a shift from early-stage to registrational development.

• Early data provided answers on active dose, administration route, and relevant clinical and biomarker endpoints, accelerating the business plan.

• Ongoing cohorts include both 4-week and 12-week dosing, with plans to update on registrational strategy in Q4.

Biomarker and dose findings

• 1 mg/kg identified as an active dose, with observed increases in frataxin mRNA and protein levels; higher doses may be explored but are not critical for advancement.

• Blood mRNA and protein data indicate treated patients reach or approach carrier levels of frataxin, considered therapeutically meaningful.

• 65% increase in frataxin mRNA and 22–27% increase in protein at two weeks post-dose support pharmacologic activity.

• Evidence of frataxin mRNA increase in muscle and broad tissue distribution, with ongoing efforts to confirm protein increases in muscle.

Clinical data and interpretation

• mFARS improvements of 6.4 points at 1 mg/kg and 5.2 points when combined with 0.6 mg/kg group exceed typical placebo and open-label responses.

• Upright stability score improvements surpass historical placebo responses, supporting clinical relevance.

• Dose response observed in both mFARS and USS, with biomarker changes correlating to clinical outcomes.

• Open-label study design aligns with approaches used by other companies for registrational purposes.