Solid Biosciences Stock Pops On US, Canada Nod For Gene Therapy Trials: Retail Buzz Spikes

Solid Biosciences drew heightened retail chatter on Tuesday following approvals for human trials by U.S. and Canadian regulators to test its gene therapy,  SGT-501, for a life-threatening heart rhythm condition called catecholaminergic polymorphic ventricular tachycardia (CPVT).

This inherited disorder commonly affects children and young adults who experience dangerous arrhythmias when stressed or exercising with no existing FDA-approved treatments available in the U.S.

Shares of the Charlestown, Massachusetts-based company, which ended Tuesday more than 6% higher, gained over 4% in after-hours trading following the announcement.

Solid Biosciences plans to launch a Phase 1b trial later this year to determine the safety and effectiveness of the therapy. 

SGT-501 holds Orphan Drug and Rare Pediatric Disease designations in the U.S. that offer development and commercialization incentives, including extended exclusivity, and accelerated reviews when the drug candidate enters an approval application stage.

The treatment employs a viral tool to introduce a functional CASQ2 gene into cardiac muscle cells. 

The CASQ2 gene encodes a protein essential for heart cells to maintain regular calcium release and uptake during each heartbeat. 

The genetic changes found in CPVT patients result in a disruption of calcium flow, which triggers abnormal heart rhythms.

The company is also advancing SGT-003, a gene therapy candidate for Duchenne muscular dystrophy (DMD). 

Last week, Citi initiated coverage on Solid with a ‘Buy’ rating and a $14 price target, citing favorable risk-reward dynamics and a cleaner safety profile for SGT-003 compared to Sarepta’s Elevidys, which has been under scrutiny following reports of liver-related fatalities.

H.C. Wainwright also maintained a ‘Buy’ rating on Solid, calling SGT-003 the most promising DMD gene therapy currently in development or on the market.

On Stocktwits, retail sentiment for Solid was ‘extremely bullish’ amid ‘extremely high’ message volume.

One user reflected on a missed opportunity, noting they “hesitated to add more” at $2.40 and now “regret it,” saying they should have purchased at least 800 shares. 

Another user questioned whether the post-news spike to $5.80 was the peak, acknowledging the announcement as “critical confirmation of our product pipeline,” but also cautioning that it’s not the same as fast-tracking or trial success.

SLDB’s stock has risen 34.4% so far in 2025.

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