Rocket Pharmaceuticals, Inc. RCKT announced encouraging preliminary data from its open-label, phase I study of its adeno-associated viral vector (AAV)-based gene therapy candidate, RP-A501. The study is evaluating single intravenous infusion of either of two doses of the LAMP2B expressing candidate for the treatment of Danon disease, a rare X-linked inherited disorder caused by genetic mutations in the LAMP2 gene. It affects cardiac muscle and other tissues and can lead to severe and frequently fatal cardiomyopathy.Preliminary data from the study showed that low-dose (6.7×1013 genome copies [gc]/kilogram) of the gene therapy candidate provided early evidence of clinical benefit and was generally well tolerated. Based on this preliminary data, the company believes that the low dose of the candidate has the potential to achieve meaningful therapeutic benefit and possibly the first viable gene therapy approach for cardiac diseases.Shares of this clinical-stage company were up 83.4% on Dec 9 following the news. Rocket Pharmaceuticals’ shares have gained 158.1% so far this year compared with the industry’s 7.5% increase. Follow-up data of up to one-year from the study showed that Cardiac LAMP2B protein expression was greater than 50% of normal as measured by immunohistochemical staining. Moreover, the treatment with the gene therapy candidate reduced two hallmarks of Danon disease — myocardial cell disarray and accumulation of autophagic vacuoles. The candidate also achieved improvement or stabilization in key clinical biomarkers including brain natriuretic peptide, creatine kinase myocardial band and transaminases.We note that patients were also administered oral steroids, Roche RHHBY/Biogen’s BIIB Rituxan (rituximab) and tacrolimus to prevent or minimize potential immune-related events. Moreover, one of the two patients who were administered the higher dose (1.1×1014 gc/kg) experienced a non-persistent, immune-related event — reversible thrombocytopenia and acute kidney injury requiring transient hemodialysis. However, the patient returned to baseline and regained normal kidney function following intensified immunosuppressive therapy.Apart from Danon disease, the company is also developing gene therapies for rare and devastating diseases. The company is developing two gene therapies for treating Fanconi anemia, a genetic defect in the bone marrow, and eukocyte adhesion deficiency-I, a genetic disorder that causes the immune system to malfunction, in registration-enabling studies in the United States and Europe. The company is also developing two other gene therapies for treating pyruvate kinase deficiency, a rare red blood cell autosomal recessive disorder, and infantile malignant osteopetrosis, a genetic disorder characterized by increased bone density and bone mass.Rocket Pharmaceuticals Inc Price Rocket Pharmaceuticals Inc price | Rocket Pharmaceuticals Inc QuoteZacks Rank & Stock to ConsiderRocket Pharmaceuticals currently carries a Zacks Rank #4 (Sell). Repligen RGEN is a better-ranked stock from the same sector, carrying a Zacks #2 (Buy). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.Repligen’s earnings per share estimates have moved up from $1.57 to $1.66 for 2021 in the past 30 days. The company delivered an earnings surprise of 37.36%, on average, in the last four quarters. The stock has risen 93.3% so far this year.Just Released: Zacks’ 7 Best Stocks for TodayExperts extracted 7 stocks from the list of 220 Zacks Rank #1 Strong Buys that has beaten the market more than 2X over with a stunning average gain of +24.4% per year.These 7 were selected because of their superior potential for immediate breakout.See these time-sensitive tickers now >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Biogen Inc. (BIIB): Free Stock Analysis Report Roche Holding AG (RHHBY): Free Stock Analysis Report Repligen Corporation (RGEN): Free Stock Analysis Report Inotek Pharmaceuticals Corporation (RCKT): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research