Creative Commons Attribution 4.0 International License. www.genediting.net www.genediting.net Review Article ©Gene Editing (2022) 03: Pages 9-13. DOI: 10.29228/genediting.67056 Gene Therapy Products Approved in 2022 Sümbül Yıldırım 1, * 1 Department of Genetics and Bioengineering, Yeditepe University, İstanbul, Türkiye *Correspondence: sumbulyldrm@gmail.com Received: 14.12.2022 Accepted/Published Online: 21.12.2022 Final Version: 25.12.2022 Key words: gene editing, cell-based gene editing, gene editing products, genetic disease 1. Introduction Gene therapy is a potential technique for creating treatments for conditions with genetic causes and those for which there is no known solution. Plasmids with the desired transgenes must be transfected into the target cells for gene therapy to be effective. Gene therapy is a method used in the treatment of diseases with a genetic basis and for diseases that currently have no cure [1]. The US Food and Drug Administration (FDA) describes gene therapy as the transmission of genetic material through transcription or translation and/or via nucleic acids, viruses, or genetically modified microorganisms that manifest their effects by integrating into the host genome [2]. When we look at the page of gene therapy products approved by the FDA, we see that currently 26 approved gene therapy products are listed [3]. In 2021, the EMA authorized Skysona for the treatment of early cerebral adrenoleukodystrophy (CALD) in patients who were age of eighteen or younger. Zynteglo is a gene therapy medicine that was authorized in 2019 for beta thalassemia [4]. This year, the FDA approved the use of these two gene therapy medicines. The gene therapy products listed here have been given FDA or EMA approval for application in 2022. 2. Gene Therapy Products Hemgenix (Etranacogene dezaparvovec) Hemophilia is a rare genetic disease caused by blood coagulation factor VIII and IX, a protein that helps blood clot to stop bleeding, deficiency. Hemophilia A and Hemophilia B are both brought on by factor VIII and factor IX deficiencies, respectively [5]. Hemophilia B affects approximately one in every 30,000 men worldwide. In the 1950s, it was considered different from hemophilia A and was named Christmas disease, taking the surname of the first affected family [6,7]. Hemgenix is an adeno-associated virus vector-based gene therapy containing a gene for coagulation factor IX, the active ingredient of which is Etranacogene dezaparvovec. The patient's liver produces factor IX protein as a result of this gene expression in the liver, which raises blood levels of factor IX and reduces the risk of bleeding incidents [8]. Etranacogene dezaparvovec, marketed as Hemgenix, is a one-time gene therapy administered by IV infusion, is a gene therapy used to treat hemophilia B. The FDA examined the safety and effectiveness of Hemgenix in two studies including 57 adult men with severe or moderate hemophilia B, aged 18 to 75. Its efficacy was determined based on reductions in annual bleeding rate (ABR) in men [9]. The study of 54 participants showed increases in patients' Factor IX activity levels and a 54% reduction in annual bleeding rate from baseline [10]. On November 22, 2022, the gene therapy product Hemgenix, produced to treat hemophilia B, was approved by the FDA [11]. That product is the first and only gene therapy treatment for hemophilia B disease. Following FDA approval, Pennsylvania- based pharmaceutical company CSL Behring LLC published its $3.5 million price tag. That price made Hemgenix the world's most expensive drug, surpassing Spinal muscular atrophy (SMA) gene therapy from Novartis, Zolgensma, which is also a single- dose drug, costing around $2 million per dose [12]. Abstract: Cell and gene therapy is a method used to treat genetically based diseases that currently have no effective treatments. The number of products available for cell and gene therapy has been rising annually in recent years. By 2025, the FDA predicts that it will have approved 10 to 20 novel cell and gene therapy products annually. The FDA's current list of authorized gene treatments includes 26 gene and cell-based products. The FDA and EMA have approved 8 cell-based and gene therapy products in 2022. We summarized the gene therapy medications authorized in 2022 in this review. Two gene therapy drugs (Skysona and Zynteglo) that were approved this year were previously approved and stopped marketing in Europe since the European market price could not be agreed upon. This year, the FDA approved the use of these two medications.