Solid Bioscience SEC Filings

Solid Biosciences (SLDB) filed its Q3 2025 report, posting a net loss of $45.8 million, driven by higher R&D as clinical programs advanced. R&D was $38.9 million (vs. $27.3 million a year ago) and G&A was $9.2 million (vs. $7.9 million). Total operating expenses reached $48.1 million.

Liquidity remained strong with $236.1 million in cash, cash equivalents and available-for-sale securities as of September 30, 2025, and management indicates funding into the first half of 2027. The company strengthened its balance sheet earlier in the year via the February 2025 offering, yielding approximately $188.0 million in net proceeds and pre-funded warrants. Derivative liabilities tied to FA212 milestones were $6.6 million at quarter-end.

Pipeline updates included progress in SGT-003 (Duchenne), with interim data (as of September 29, 2025) described in the filing, ongoing screening for SGT-212 (FA), and IND/CTA clearances for SGT-501 (CPVT). Shares outstanding were 77,910,239 as of October 29, 2025.

Solid Biosciences (SLDB) filed an 8‑K announcing positive interim clinical data and a corporate update for SGT‑003, its gene therapy for Duchenne muscular dystrophy. The Phase 1/2 INSPIRE DUCHENNE trial has dosed 23 participants across 15 sites, with dosing expected to reach 30 by early 2026.

At Day 90 (N=10, ages 5–10), mean microdystrophin expression was 58% by western blot and mass spectrometry, and 51% microdystrophin‑positive fibers by immunofluorescence. Strong correlations linked microdystrophin to restoration of DAPC components, including beta‑sarcoglycan (0.95) and nNOS activity (0.95). Biomarkers of muscle injury improved, with mean reductions at Day 90 in CK, ALT, AST and LDH, and further improvements observed in limited Day 360 data. Early cardiac monitoring showed LVEF trending into normal ranges at Day 180 (N=8) and cTnI reductions.

Safety was generally favorable with steroids alone for prophylaxis; one treatment‑related Grade 3 immune‑mediated myositis resolved after steroid treatment, and dosing continued. The company plans to meet the FDA in the first half of 2026 to discuss potential registrational pathways and has initiated the Phase 3 IMPACT DUCHENNE study outside the U.S., with approvals in Canada and Australia.

Solid Biosciences (SLDB) Form 4: Chief Medical Officer Gabriel Brooks reported RSU vesting and a related tax sale. On 10/18/2025, 9,750 restricted stock units converted to common stock on a one-for-one basis. On 10/20/2025, 2,895 shares were sold at $5.96 to cover withholding taxes under a previously adopted durable automatic sale instruction letter, characterized as a sell-to-cover and not a discretionary trade.

Following these transactions, Brooks beneficially owned 33,819 common shares, held directly. The filing notes an additional 19,500 RSUs beneficially owned after the reported transactions. The RSU grant from 10/18/2023 vests over four years at 25% on each anniversary of the grant date.

Solid Biosciences Inc. director Ian F. Smith reported receipt of 4,573 restricted stock units that convert one-for-one into common shares. The filing shows the RSUs were granted on 01/06/2025 and, per the grant terms, vest in equal quarterly installments beginning three months after the grant with final vesting 12 months after the grant date. The report records the RSUs as acquired on 10/06/2025 and notes the units accelerate in full if the executive chair agreement terminates early or if there is a change in control. After the transaction the reporting person beneficially owns 126,692 shares of common stock. The filing was signed by an attorney-in-fact on 10/07/2025.

Form 4 filed for Ilan Ganot (director) reports option and restricted stock unit grants on 08/14/2025. The reporting person received an employee stock option to buy 37,500 shares at an exercise price of $6.17, exercisable through 08/14/2035. In addition, 18,750 restricted stock units (RSUs) were granted, each representing the contingent right to one share. Both holdings are reported as indirectly beneficially owned (I) via wife. The RSUs and option vest over four years, with 50% vesting on the second anniversary of the August 14, 2025 grant date and 25% each year thereafter. The Form 4 was signed by an attorney-in-fact on behalf of Mr. Ganot on 08/18/2025.

Solid Biosciences Inc. reported that its Chief Operating Officer, David T. Howton, was granted equity awards on 08/14/2025 consisting of an employee stock option to buy 150,000 shares at an exercise price of $6.17 per share with an expiration date of 08/14/2035, and 75,000 restricted stock units (RSUs) that each convert into one share. After these grants, Mr. Howton beneficially owns 150,000 option shares and 75,000 RSUs, all held directly. The RSUs and the option vest over four years: 50% vests on the second anniversary of the grant and 25% vests on each of the third and fourth anniversaries.

Kevin Tan, CFO & Treasurer of Solid Biosciences Inc. (SLDB), received equity awards on August 14, 2025. The Form 4 shows a grant of 125,000 employee stock options with an exercise price of $6.17 and 62,500 restricted stock units (RSUs), each RSU representing a right to one share. The awards vest over four years: 50% of the original shares vest on the second anniversary of the grant and 25% vest annually thereafter until the fourth anniversary. Following the reported transaction, Mr. Tan beneficially owns 125,000 shares from the option and 62,500 shares from RSUs as direct ownership. The Form 4 was signed by Kimberly Cornwell as attorney-in-fact on 08/18/2025.

Paul Herzich, Chief Technology Officer of Solid Biosciences Inc. (SLDB), reported equity awards granted on 08/14/2025. The filing shows an employee stock option for 100,000 underlying shares with a stated exercise price of $6.17 and an associated record showing 100,000 shares of common stock underlying that option. The filing also reports 50,000 restricted stock units (RSUs), each representing a contingent right to one share, for 50,000 shares of common stock. The RSUs and the option were granted on the same date and the RSUs vest over four years: 50% on the second anniversary of the grant and 25% annually thereafter until the fourth anniversary. The Form 4 was signed by an attorney-in-fact on behalf of Mr. Herzich on 08/18/2025.

Solid Biosciences Inc. (SLDB) reported an equity award to Chief Medical Officer Gabriel Brooks comprised of an employee stock option to purchase 142,500 shares at an exercise price of $6.17 and 71,250 restricted stock units (RSUs), both granted on 08/14/2025. The option expires on 08/14/2035 and both awards are held directly by the reporting person. The RSUs convert on a one-for-one basis to common stock. The awards vest over four years: 50% of the original shares vest on the second anniversary of the grant and 25% of the original shares vest each year thereafter until the fourth anniversary. The Form 4 was signed by an attorney-in-fact on 08/18/2025.