U.S. Regulatory Challenges for Gene Editing

Abstract

Researchers are now realizing the promise of molecular biology and genomic engineering. In the United States, President Obama has prioritized innovations in genomic research and therapies with funding infusions into national programs such as the Precision Medicine Initiative and the Cancer Moon Shot 2020. More than a decade after the completion of the Human Genome Project, our understanding of the human genome has now ushered us into the era of genetic modification capabilities known as genome editing, or gene editing. Building on the scientific foundation of recombinant DNA (rDNA) technology and human gene transfer research, gene editing enables the alteration of the genetic make-up in a manner that was previously only a theoretical possibility. Current gene editing technology improves on prior cellular-based therapies and gene therapies because it directly targets nucleotides in the defective gene. Following the discoveries of zinc finger nuclease (ZFN) and transcription activator-like effector nuclease (TALEN), a technique known as clustered regulatory-interspaced short palindromic repeat (CRISPR) is the most precise, efficient, and least expensive method of gene editing to date. First described in 2012, CRISPR-Cas9 uses the Cas9 enzyme and an RNA guide sequence to target a particular gene sequence, remove the faulty gene, and insert a new functioning gene and fuse the genetic strand back together. New variants of the CRISPR technology are currently being explored.CRISPR is garnering significant attention in the U.S. for both its relative simplicity over previous gene editing techniques and for its potential long-term commercial impacts. Shortly after the publication of the CRISPR discovery in Science, several leading gene editing scientists formed Editas Medicine in Cambridge, Massachusetts with a $43 million capital investment to design clinical trials based on the CRISPR and TALEN platforms. Reports indicate that Editas is projected to begin clinical trials by 2017 for a rare retinal disorder called Leber congenital amaurosis. But Editas is not the only player. Many of the early researchers involved in developing the CRISPR technology, including Jennifer Doudna (Caribou Biosciences) and Emmanuelle Charpentier (CRISPR Therapeutics) have also formed companies to develop applications using the CRISPR system. Recently on June 2016, the National Institutes of Health (NIH) Recombinant DNA Advisory Committee (RAC) approved a University of Pennsylvania protocol applying CRISPR) to genetically modify human T-cells in fifteen individuals suffering from multiple myeloma, melanoma, and sarcoma. Funded by the new Parker Institute for Cancer Immunotherapy, and led by Dr. Carl June, the clinical trial protocol has yet to be reviewed and approved by the appropriate institutional bodies and the U.S. Food and Drug Administration (FDA). Although in early stages of regulatory approval, the June 2016 decision of the RAC sheds new light on the ongoing debate regarding the ethical and legal implications of gene editing research. Concern about gene editing has inspired a broad global discussion in scientific and bioethics communities as to proper regulation and whether to halt future research on germline, or heritable, applications. This global discussion is nestled in the rich history of genetic research and the existing federal frameworks in place to oversee clinical trials, as well as the distinction between somatic and germline interventions. This article will examine the current regulatory landscape for gene editing research in the U.S. as positioned within the historical context and recent developments in this area.