Monday, Dyne Therapeutics Inc ( DYN ) released clinical data from its ongoing Phase 1/2 ACHIEVE trial of DYNE-101 in patients with myotonic dystrophy type 1 (DM1) and its ongoing Phase 1/2 DELIVER trial of DYNE-251 in patients with Duchenne muscular dystrophy (DMD) who are amenable to exon 51 skipping. 

Earlier this year, Dyne Therapeutics ( DYN ) released initial clinical data from both trials.

In the ACHIEVE trial, patients in the 5.4 mg/kg Q8W cohort had a 27% mean splicing correction from baseline across a broad, 22-gene panel at 3 months, with all participants demonstrating splicing correction.

DYNE-101 demonstrated an improvement in myotonia as measured by video hand opening time (vHOT) in all reported cohorts. 

The 1.8 mg/kg Q4W group had a mean 3.1-second benefit in myotonia at 3 months, increasing to 4.4 seconds at 12 months. 

In addition, the 5.4 mg/kg Q8W cohort had a mean 4.5-second improvement in myotonia at 3 months.

DYNE-101 demonstrated an improvement in muscle strength and early and sustained potential benefit in the 10-meter Walk/Run Test and 5-times to Stand Test.

Dyne reported efficacy data from 8 male patients with DMD amenable to exon 51 skipping enrolled in the 10 mg/kg (approximate PMO dose) cohort of the randomized, placebo-controlled MAD portion of the DYNE-251 DELIVER trial.

10 mg/kg of DYNE-251 Q4W demonstrated dose-dependent exon skipping and dystrophin expression. 

DYNE-251 reached levels of dystrophin expression that exceeded levels reported in a clinical trial for the current weekly standard of care for DMD exon 51, eteplirsen, at 6 months1 with a 12-fold lower PMO dose. 

DYNE-251 also demonstrated encouraging trends in multiple functional endpoints.

Patients treated with 10 mg/kg of DYNE-251 Q4W had a mean absolute dystrophin level of 3.22% of normal and a 2.97% change (unadjusted for muscle content) from baseline at 6 months. 

Eteplirsen reached a mean absolute unadjusted dystrophin level of 0.30% of normal and a 0.06% change from baseline at 6 months.

When adjusting for muscle content, the DYNE-251 treated group reached 7.64% mean absolute dystrophin, greater than levels reported by peptide conjugate PMOs in clinical development.

Trends in improvement were observed in multiple functional endpoints in the 10 mg/kg DYNE-251 Q4W group at 6 months.

Price Action: DYN shares are up 27.80% at $35.36 at the last check Monday.