MSLE: Second TRAILHEAD update incrementally de-risks BASECAMP

Research evidence excerpt

MSLE: Second TRAILHEAD update incrementally de-risks BASECAMP

July 8, 2026

●Total effort (TE99C), the other first-time endpoint: TE99C is a

wearable-based measure of maximal upper-limb effort reported

in joules and captured passively during daily life via wrist and

ankle devices; conceptually TE99C is the upper-limb, non-ambulant

analogue of SV95C. Measured from a CL-101 baseline of 16.1J/kg to

21.6J/kg at Day 140, a ~34% increase across participants.

●Hand-grip strength maintained: the ~2x grip gains first shown in

CL-101 continued to be held at the 6-month visit, consistent with the

durability theme from the first TRAILHEAD update.

●CK declined ~38%: creatine kinase fell roughly 38% from the CL-101

(Phase 1b) baseline to Day 140. Management framed the adult CK

picture as more uniform and stable than the pediatric pattern, and

views it as consistent with the Day 15 proteomic improvements shown

at MDA.

●PUL 2.0 stable to improved: two of four participants gained a point and

two remained stable, against a natural-history expectation of decline

in adult DMD.

●Correlation with baseline muscle mass: for both MRI fat fraction

and total effort, the gains generally tracked baseline creatinine (a

muscle-mass surrogate), consistent with the first TRAILHEAD update.

Management hypothesizes the magnitude of benefit may depend on

how much muscle a patient has at treatment start.

What we think

We view the update as a meaningful, incrementally de-risking event

for BASECAMP: it adds objective, blinded-evaluator structural data

(muscle MRI) and a first-time wearable effort measure to the previously

reported grip and biomarker results; and the consistency of improvements

strengthens the case that SAT-3247 is doing something clinically relevant

even in severely compromised adult muscle.