Entrada Therapeutics reports early dystrophin and exon-skipping changes with ENTR-601-45 in Duchenne muscular dystrophy, with functional benefit still unestablished.
Written By: Malavatu Satvika, PharmD
Reviewed By: Pharmacally Editorial Team
Entrada Therapeutics reported topline results from Cohort 1 of the Phase 1/2 ELEVATE-45-201 study (NCT07038824) evaluating ENTR-601-45 in ambulatory participants with Duchenne muscular dystrophy (DMD) whose genetic mutations are amenable to exon 45 skipping. The initial findings showed favorable safety and tolerability at 5 mg/kg, alongside early changes in dystrophin production and exon skipping after three doses. However, the small cohort and absence of observed functional benefit limit conclusions about the treatment’s clinical potential.
Initial Safety Findings at 5 mg/kg
Cohort 1 enrolled eight participants randomized in a 3:1 ratio to receive intravenous ENTR-601-45 at 5 mg/kg or placebo. Participants received doses on Days 1, 43, and 85. Muscle biopsies were performed at baseline and six weeks after the final dose.
The study met its primary objectives for safety and tolerability. Headache was the most common treatment-emergent adverse event, with five events reported in two participants. One participant experienced two serious treatment-emergent adverse events, vomiting and pyrexia, both of which subsequently resolved. No participants discontinued the study, and all progressed to the open-label extension.
The company reported no hypomagnesemia or renal safety concerns. Renal markers, including estimated glomerular filtration rate and cystatin C, remained within normal ranges in treated participants. Magnesium levels also remained within the normal range.
Plasma ENTR-601-45 exposures were consistent with predictions based on juvenile non-human primate data. This finding supports continued clinical evaluation and dose escalation, although it does not establish whether higher exposures will produce greater dystrophin production or improve clinical outcomes.
Dystrophin Production and Exon-Skipping Results
Treated participants showed a mean increase of 0.10% in dystrophin production from baseline (n=6), compared with a mean decrease of 0.02% in the placebo group. The dystrophin result had a nominal p-value of 0.03.
Dystrophin was measured using Western blot and normalized to myosin heavy chain. Two treated participants had baseline dystrophin measurements below the assay’s lower limit of quantification, although the values remained above its limit of detection. This analytical limitation is relevant when interpreting the findings from such a small cohort.
Mean exon skipping increased by 0.15% from baseline in treated participants (n=5), compared with a mean decrease of 0.04% in the placebo group. No p-value was calculated for the exon-skipping result.
These findings provide preliminary evidence of biological activity at the initial dose. However, the limited number of evaluable participants and the small magnitude of the reported changes make it difficult to determine their biological and clinical significance. The nominal p-value for dystrophin production should not be interpreted as proof of treatment efficacy.
Functional Benefit Remains Unestablished
According to the company, no observable functional benefit was expected or observed after the three initial doses. Functional effects will be assessed with higher doses and longer treatment periods.
All Cohort 1 participants progressed to the open-label Phase 2 portion, where they will receive six additional doses of ENTR-601-45 at 5 mg/kg. Enrollment in Cohort 2, which evaluates 10 mg/kg, is complete, with results expected in the first half of 2027. Cohort 3 will evaluate doses up to 15 mg/kg, with results expected subsequently.
The higher-dose cohorts should help clarify whether increased exposure produces a more substantial pharmacodynamic response. Longer follow-up will also be needed to determine whether any biomarker changes translate into measurable improvements in motor function or disease progression.
A Targeted Approach to Exon 45 Skipping
ENTR-601-45 is an investigational oligonucleotide conjugate designed for people with DMD mutations amenable to exon 45 skipping. Exon skipping aims to restore the messenger RNA reading frame, potentially enabling production of a shorter form of dystrophin that retains some function.
The therapy uses Entrada’s Endosomal Escape Vehicle (EEV) platform and is designed for intravenous administration once every six weeks. Whether this dosing interval can provide meaningful clinical benefit or offer a practical advantage over existing treatments remains to be established.
Clinical Interpretation
The ELEVATE-45-201 Cohort 1 results provide preliminary evidence of biological activity and favorable initial tolerability at 5 mg/kg. The observed changes in dystrophin production and exon skipping support further investigation, but they do not demonstrate improved muscle function or establish clinical benefit for patients.
Interpretation remains limited by the small cohort, the number of participants contributing to each biomarker analysis, and the assessment following only three doses. Although the dystrophin finding had a nominal p-value of 0.03, the result requires confirmation in larger datasets and should not be treated as evidence of clinical effectiveness. Pharmacokinetic findings support continued dose escalation, but results from higher-dose cohorts and longer-term functional assessments will be essential to determine whether the early biological signals translate into meaningful patient outcomes.
Reference
Entrada Therapeutics Announces Positive Results from the First Cohort of Participants with Duchenne Muscular Dystrophy (DMD) in the Phase 1/2 ELEVATE-45-201 Study of ENTR-601-45, Entrada Therapeutics, 14 October 2026
A Study in Participants with Duchenne Muscular Dystrophy Amenable to Exon 45 Skipping to Evaluate the Safety and Efficacy of ENTR-601-45 (ELEVATE-45), ClinicalTrials.gov ID NCT07038824
About the Writer
Malavatu Satvika (Linkedin) is a Pharm.D professional and aspiring healthcare medical writer with clinical exposure and research experience. Her interests include medical writing, drug safety, pharmaceutical research, and evidence-based healthcare communication. She has contributed to two research publications in pharmaceutical journals and has gained practical experience in prescription review, patient counselling, medication review, adverse drug reaction monitoring, drug information services, literature review, and clinical documentation through regular hospital training.
She has completed certifications in clinical research, ICH-GCP E6(R3), data management for clinical research, and congenital hypothyroidism. With a strong foundation in pharmacy, clinical practice, and scientific research, she aims to translate complex medical and pharmaceutical information into accurate, clear, and evidence-based healthcare content. She is also preparing to pursue a PhD and further develop her expertise in medical writing and pharmaceutical research.