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SOLID BIOSCIENCES Solid Biosciences Provides First Quarter 2021 Business Update and Financial Results May 14 , 2021 -Patients 7 and 8 dosed in IGNITE - DMD Phase I / II clinical trial under new clinical protocol and second - generation SGT - 001 manufacturing process ; patient 8 experienced a serious adverse event - - Long - term biopsy data generated from the ongoing IGNITE DMD trial demonstrate durable microdystrophin expression as measured up to two years post dosing of SGT - 001 . Data to be presented today at ASGCT at 1:45 PM ET - - Continued research and innovation in musculoskeletal therapy generates next - generation DMD gene transfer candidate , SGT - 003- - Company ends Q1 with $ 268.5 million in cash ; cash runway into Q4 2022 - - Company to hold conference call at 8:30 am ET today - CAMBRIDGE , Mass . , May 14 , 2021 ( GLOBE NEWSWIRE ) -- Solid Biosciences Inc. ( Nasdaq : SLDB ) , a life sciences company focused on advancing meaningful therapies for Duchenne muscular dystrophy ( Duchenne ) , today provided a first quarter 2021 business update , which includes updates on two additional patients dosed in the IGNITE DMD clinical trial , long term biopsy data from prior patients dosed in the high dose 2E14 vg / kg cohort of the trial , advancement of a next - generation gene therapy program for Duchenne and financial results for the quarter ended March 31 , 2021 . " We are pleased to have progressed with dosing patients in our IGNITE DMD trial and will continue monitoring patient outcomes as discussions with our Data Safety Monitoring Board ( DSMB ) on the safety and efficacy profile of SGT - 001 are ongoing . We also announced data that will be presented later today at the American Society of Gene & Cell Therapy ( ASGCT ) annual meeting that demonstrate sustained microdystrophin expression for up to two years post - dosing , " said Ilan Ganot , Chief Executive Officer , President and Co - Founder of Solid Biosciences . " We are excited by the durability of the microdystrophin protein observed in these patients , and the potential for the meaningful impact this may have on their lives . " IGNITE DMD Clinical Trial Update Solid Biosciences has continued patient dosing in IGNITE DMD with SGT - 001 using Solid's improved manufacturing process and under an amended clinical protocol designed to enhance patient safety . As previously reported . Patient 7 was dosed uneventfully and continues to do well . In April 2021 , an eighth patient , also in the 2E14 vg / kg cohort , was treated with SGT - 001 . The patient experienced an inflammatory response which was classified as a serious adverse event and considered by the investigator to be drug - related . This type of event is described in our investigators brochure and is not considered unexpected . As of the patient's 30 - day follow - up visit , laboratory values had either returned to normal or continue to trend towards normal . As part of Solid's clinical mitigation strategy , the status of both patients dosed under the amended protocol have been shared with the Company's DSMB as well as the Food and Drug Administration ( FDA ) . The Company is carefully examining the full details of the clinical course of these patients and is continuing its discussions with these two bodies . No new drug - related safety findings have been identified in Patients 1 through 6 who have post dosing periods of 1.5 years to more than 3 years . IGNITE DMD Long Term Biopsy Data Update Today the Company will share long - term biopsy data collected from patients 4-6 at the 2E14 vg / kg dose level . Analyses of the biopsies , taken 2 years , 1.5 years and 1 - year post - dosing , respectively , indicate evidence of durable and widespread expression of the microdystrophin protein . The long - term results are consistent with the Day 90 data previously reported and continue to demonstrate the functionality of the SGT - 001 microdystrophin , as highlighted by the recruitment of key dystrophin associated proteins : beta - sarcoglycan and neuronal Nitric Oxide Synthase ( nNOS ) . The long - term muscle biopsy results were analyzed by two methods , Western Blot and Immunofluorescence ( IF ) , and are provided in the table below : Patient Last Timepoint Western Blot Immunofluorescence ( % Positive Fibers ) Day 90 Pt . 4 24 months BLQ * Pt . 5 18 months 17.5 % Pt . 6 12 months 8.0 % Last Timepoint BLQ 69.8 % 20.3 % Day 90 10-20 % 50-70 % 50-70 % Last Timepoint 10-30 % 85 % 50-60 % * Below the limit of quantification In summary , the Western Blot data indicate that expression was maintained in Patient 4 and increased compared to the Day 90 biopsies in Patient 5 and 6. IF data show microdystrophin function via continued localization to the muscle membrane , with the percent positive fibers remaining comparable to the Day 90 biopsies in all three patients . Further morphological analyses of the muscle biopsies indicate that sustained microdystrophin protein expression and function resulted in membrane stabilization , evidenced by minimal progression of muscle deterioration since the Day 90 timepoint . These long - term pathophysiological improvements are potentially supportive of the recently reported positive trends in the clinical biomarker and functional data from the IGNITE DMD trial . These data will be presented today by Dr. Carl Morris , PhD at 1:45 PM ET at the ASGCT 24th Annual Meeting ( Abstract # 263 ) . R & D Pipeline Update