Design Therapeutics Inc. (NASDAQ:DSGN) stock surged during the premarket session on Monday.

The move came after the company reported biomarker and clinical findings from its ongoing Phase 1/2 RESTORE-FA trial evaluating DT-216P2 in patients with Friedreich ataxia, a rare degenerative genetic disease.

However, later during the day, the stock fell.

On Sunday, Design Therapeutics was among Jim Cramer's Mad Money stock calls as he urged investors to exercise caution when it comes to red-hot AI stocks.

DT-216P2 Demonstrates Clinical And Biomarker Improvements

The company said the experimental GeneTAC small-molecule therapy produced dose-dependent increases in frataxin (FXN) levels while also improving multiple clinical measures after four weeks of treatment.

RESTORE-FA Trial Data Highlights

As of May 17, 2026, 16 patients had completed weekly intravenous treatment across four dose cohorts ranging from 0.1 mpk to 1 mpk.

Patients treated at the highest 1 mpk dose showed a mean improvement of 6.4 points from baseline on the modified Friedreich's Ataxia Rating Scale after four weeks.

The cohort also demonstrated a 2.7-point improvement in the upright stability score.

The company additionally reported greater than five-point reductions in patient-reported fatigue scores, both after treatment and two weeks following the final dose.

Design Therapeutics noted that these improvements exceeded the commonly recognized three-point threshold for meaningful fatigue changes.

Biomarker Activity And Safety Findings

The company said DT-216P2 generated dose-dependent increases in FXN messenger RNA and protein levels in both blood and muscle tissue.

At the 1 mpk dose, whole blood FXN mRNA levels increased 65% from baseline, while FXN protein levels rose between 22% and 27% two weeks after the last dose. Muscle FXN mRNA levels increased 42% from baseline.

Design Therapeutics said DT-216P2 was generally well tolerated, with no serious adverse events or treatment discontinuations reported. All adverse events were classified as mild or moderate.

The company said it plans to pursue a registrational path for DT-216P2 and expects to provide an update on development plans during the fourth quarter of 2026.

DSGN Price Action: Design Therapeutics shares were down 28.88% at $10.22 at the time of publication on Monday, according to Benzinga Pro.

Over the past month, DSGN has gained about 21.0% versus a 4.0% rise in the S&P 500 and is up roughly 67% year-to-date compared to the index's 7.5% gain.

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