Price Target Changed • May 15
Price target decreased by 13% to US$24.18 Down from US$27.82, the current price target is an average from 11 analysts. New target price is 323% above last closing price of US$5.72. Stock is down 36% over the past year. The company is forecast to post a net loss per share of US$2.83 next year compared to a net loss per share of US$3.76 last year. Announcement • May 15
Regenxbio Inc Announces Positive Topline Results from Pivotal Phase Iii Affinity Duchenne Study of Rgx-202 Regenxbio Inc. announced positive topline and interim functional data from the pivotal Phase III portion of the Phase I/II/III AFFINITY DUCHENNE trial of RGX-202, a potential best-in-class gene therapy for Duchenne Muscular Dystrophy. The trial met its primary endpoint with high statistical significance. The pivotal portion of the Phase I/II/III AFFINITY DUCHENNE trial evaluated RGX-202 at 2x1014 GC/kg in 31 ambulatory boys aged 1 year of age and older. Key topline interim results include safety (n=31), biomarker (n=30), and functional data (n=9 aged >4 years, 12 months post-treatment). More than 20 additional participants have been enrolled in the confirmatory trial of RGX-202 (n=30), and the Company expects to have completed dosing in all 60 patients across the pivotal and confirmatory trials by mid-year. 93% of participants achieved >10% RGX-202 microdystrophin expression at Week 12. Additionally, 80% of participants achieved >40% microdystrophin expression. RGX-202 was appropriately localized to the sarcolemma, demonstrating that the differentiated construct with the inclusion of the C-Terminal (CT) domain is appropriately targeting the muscle. Additionally, robust vector copies per nucleus and percent positive fibers observed support the potential for sustained microdystrophin expression. RGX-202 was well tolerated and demonstrated a favorable safety profile as of last data cut. A proactive, short-course immune suppression regimen in combination with a differentiated construct and industry-leading product purity levels of more than 80% full capsids may contribute to a favorable safety profile for RGX-202. Mean gamma-glutamyl transferase (GGT) and total bilirubin, recognized markers of liver inflammation in Duchenne, did not exceed the upper limit of normal up to one year post-treatment (n=9). Two serious adverse events were reported; both were easily managed and resolved within weeks without sequelae. One case of subacute myocarditis was reported in an 8-year-old participant. The participant's most recent cardiac MRI confirmed no heart muscle fibrosis and no change in ejection fraction. One case of asymptomatic liver injury was reported in a 10-year-old participant. This patient's GGT peak elevation was 123 U/L, and his abdominal ultrasound and bilirubin levels were normal. Common drug-related adverse events included vomiting, fatigue, and nausea, all considered mild or moderate, and resolved without sequelae. In interim functional results from nine participants aged approximately 5 to 12 years at dosing, RGX-202 demonstrated functional improvement and evidence of positively impacting disease trajectory at one year post-treatment, as measured by North Star Ambulatory Assessment (NSAA) and timed function tests (Time to Stand, 10 Meter Walk-run, Time to Climb). Participants demonstrated statistically significant improved performance across NSAA and all timed function tests when compared to external control using propensity score weighting, which is the primary analysis method specified in the SAP for the pivotal trial. RGX-202 microdystrophin expression at Week 12 demonstrated a statistically significant correlation with functional improvement at one year as measured by NSAA change from baseline (correlation= .094, p = 0.0002) and NSAA change from baseline compared to the cTAP predictive model (correlation= .092, p = 0.0005). In recent discussions with FDA, the agency shared that the use of RGX-202 microdystrophin expression as a surrogate endpoint will be based on the correlation analysis with clinical outcomes, which has been clearly demonstrated in the interim data. While the FDA has recommended a randomized controlled trial, it has guided that externally controlled trials may be adequate for demonstrating substantial evidence of effectiveness, especially when the treatment effect is sufficiently large enough to overcome limitations of externally controlled trials. RGX-202 is designed to address the underlying cause of Duchenne by enabling targeted expression of a novel microdystrophin that is closest to naturally occurring dystrophin. It is the only microdystrophin that includes the C-Terminal domain, which has been shown to protect and preserve muscle function. The differentiated therapeutic approach behind RGX-202 includes a novel construct, a proactive immune suppression regimen, and a suspension-based manufacturing process that delivers industry-leading product purity levels. RGX-202 is designed for improved muscle function, durability and safety outcomes for patients. 
