CMN Weekly (6 January 2023) - Your Weekly CRISPR Medicine News

Top picks

• Genomic medicines company Ensoma announced yesterday $85 million in financing and an agreement to acquire Danish company Twelve Bio to advance its portfolio of in vivo engineered cellular medicines. Ensoma is leveraging its Engenious™ platform to develop one-time in vivo treatments that precisely engineer any cell of the haematopoietic system. Twelve Bio is a pioneer in CRISPR-Cas12a gene editing with foundational insights from a number of significant discoveries through X-ray crystallography and cryogenic electron microscopy.
• Scientists at Brigham and Women’s Hospital in the US have developed a new strategy to combat cancer by repurposing cancer cells into therapeutic tumour cells (ThTCs). By CRISPR-editing the genomes of living cancer cells to release anti-cancer drugs at the site of established tumours, as well as stimulating the immune system to attack tumours in mouse models of advanced glioblastoma, the team demonstrated the potential for a therapy and a preventative vaccine, with evidence of increased survival rates, safety and long-term immunity. The findings were published this week in Science Translational Medicine.

Industry

• Mayflower Bioventures launches its first spin-out, Primera Therapeutics, in a strategic collaboration with Cellectis to develop a gene-editing platform to treat mitochondrial diseases. Mayflower Bioventures is a cell and gene therapy accelerator stood up from Hibiscus BioVentures and Mayo Clinic (US). Primera’s initial clinical focus is on rare mitochondrial diseases for which there are no approved treatments.
• Graphite Bio announced yesterday a voluntary pause of its ongoing Phase 1/2 CEDAR study of nulabeglogene autogedtemcel (nula-cel) for sickle cell disease (SCD). Nula-cel is the first CRISPR-based therapy designed to correct the causative mutation in SCD; CRISPR-based correction of the beta-globin (HBB) gene will decrease sickle haemoglobin (HbS) production and restore adult haemoglobin (HbA) expression, thereby potentially curing SCD by restoring completely normally-functioning red blood cells. The annoucement of the voluntary pause follows a serious adverse event in the first patient dosed with nula-cel, and the company’s conclusion that the event is likely related to study treatment. As a result, the company will not meet its guidance for initial proof-of-concept data in mid-2023. See full details in press release from Graphite Bio here.
• ArsenalBio has announced dosing of the first patient in a Phase 1 clinical trial of AB-1015, which is being developed as a treatment for ovarian cancer. According to the company's press release, AB-1015 is ArsenalBio’s first internally discovered T cell medicine to enter clinical development, and it involves the use of synthetic DNA programming to overcome tumour defenses, increase potency, and target ovarian cancer cells without harming normal tissues.
• ONK Therapeutics (Ireland and US) is named most promising company in BioSpace’s NextGen 2023 List. The company is developing optimally-engineered natural killer (NK) cell therapies to cure patients with cancer, which is made possible through a number of licencing agreements, e.g., agreements covering the use of CRISPR/Cas9 gene-editing and lipid nanoparticle delivery technologies from Intellia Therapeutics. The company's growing pre-clinical pipeline targets both haematological malignancies and solid tumours, while it is also advancing multiple cell therapy candidates towards the clinic, including its lead programme, ONKT102, an optimised affinity CD38 CAR-NK product, intended for the treatment of patients with relapsed or refractory multiple myeloma.
• Integra Therapeutics has acquired a licence for a new CRISPR system from CIC nanoGUNE. The new system was discovered by an international research group led by Dr Raúl Pérez-Jiménez from CIC nanoGUNE (details of which were published in Nature Microbiology this week) and uses Cas9 proteins dating back 2.6 billion years.
• Metagenomi announced yesterday that it had closed an oversubscribed Series B Financing round totalling $275M. The funding is planned to advance the company's lead therapeutic programmes into clinical development and to grow the company's genetic medicines pipeline.
• In a press release published yesterday, Intellia Therapeutics highlighted its strategic priorities and anticipated 2023 key milestones. The company ended 2022 in a strong financial position with approximately $1.3 billion in cash, and among the key milestones for 2023 are plans to focus on late-stage development of the company's CRISPR-based medicines, as well as submission of IND applications for NTLA-2001 for the treatment of transthyretin (ATTR) amyloidosis with cardiomyopathy, for NTLA-2002 for the treatment of hereditary angioedema and plans to initiate a global Phase 2 study in 1H 2023. The company also expects to present additional clinical data in 2023 from both ongoing NTLA-2001 and NTLA-2002 first-in-human studies.

Research and detection

• In two articles published in the same edition of Nature this week, scientists at Utah State University (US), Helmholtz Institute for RNA-based Infection Research (Germany), biotechnology company Benson Hill (US), and the University of Texas at Austin (US) described the structure and function of a novel CRISPR nuclease. Cas12a2 is a CRISPR-associated nuclease that performs RNA-guided, sequence-nonspecific cleavage of single-stranded RNA, single-stranded DNA and double-stranded DNA following recognition of a complementary RNA target, activities that result in abortive infection in bacteria. Such bacterial abortive-infection systems limit the spread of foreign invaders by shutting down or killing infected cells before the invaders have a chance to replicate. These new studies provides a structural basis for Cas12a2's mechanism of abortive infection, and demonstrate the potential to harness the collateral activity of Cas12a2 for direct RNA detection, revealing that Cas12a2 can be repurposed as an RNA-guided RNA-targeting tool.
• In an article published earlier this week in Current Protocols, scientists in Germany provide step-by-step instructions to prepare and perform double-control quantitative copy number PCR (dc-qcnPCR) — a recently described tool that can be used to quantify donor DNA insertions in genetically modified monoclonal cell lines — and its companion insert-confirmation PCR, to determine donor DNA insertion numbers in monoclonal cell lines genetically modified through CRISPR/Cas9.
• In an article published yesterday in Analytical Chemistry, Scientists in China propose the first CRISPR/Cas13a-mediated photoelectrochemical biosensors for the direct assay of miRNA-21, a small regulatory RNA that is believed to play a crucial role in many biological functions and diseases including development, cancer, cardiovascular diseases and inflammation. In the new study, compared with traditional nucleic acid-based signal amplification strategies based on Cas12a, the CRISPR/Cas13a system could greatly improve the specificity and sensitivity of target determination due to its accurate recognition and high-efficient trans-cleavage capability without complex nucleic acid sequence design. The team demonstrated excellent sensitivity with a lower detection limit of 1 fM, as well as satisfactory stability in the detection of human serum samples and cell lysates.
• In a new study, results of which were published yesterday in Microbiology Spectrum, a team of scientists report that genome-wide profiling of 3,156 mycobacterial genomes led to the identification of the CRISPR-csm4 gene as specific for Mycobacterium tuberculosis (MTB). Using real time (RT)-PCR and PCR-sequencing of CRISPR-csm4, tested on a collection of 20 Mycobacterium tuberculosis complex (MTC) and 5 nontuberculous mycobacteria, the team confirmed the 20 MTC isolates, whereas the 5 nontuberculous isolates were not detected. The study revealed that whole-genome sequence comparison of the MTC genomic sequences available in the NCBI database identified a unique, specific gene to be used directly on clinical diagnostic samples to detect MTC against all species of mycobacteria and to differentiate between MTC species, lineages, and sublineages.
• In an article published online in PNAS, a team of scientists in France, UK, Monaco and Germany demonstrate that genome-level correction in X-linked muscular dystrophy mice via CRISPR-Cas9 gene editing could restore a mosaic of separated dystrophin domains, while transcript-level Dmd correction, following treatment with tricyclo-DNA antisense oligonucleotides, restored dystrophin initially at junctions before extending along the entire fiber-with levels ~2% sufficient to moderate the dystrophic process. Based on their findings, the team concludes that widespread restoration of fiber dystrophin is likely critical for therapeutic success in Duchenne muscular dystrophy, perhaps most importantly, at muscle-tendon junctions.

Reviews

• A critical review of microfluidic systems for CRISPR assays. This review gives an overview on nucleic acid detection assays that incorporate CRISPR-based diagnostics and microfluidic devices and techniques. The review is intended as a reference for researchers who wish to use CRISPR-Cas systems for diagnostics in microfluidic devices.
• CRISPR-interceded CHO Cell Line Development approaches. This review overview the most fundamental recent advancements in Chinese Hamster Ovary (CHO) cell line development, such as different cell line engineering approaches along with donor design strategies for targeted integration of the desired construct into genomic hot spots, which could ultimately lead to the fast-track product development process with consistent, improved product yield and quality.
• Amplification-free CRISPR/Cas detection technology: challenges, strategies, and perspectives. In this review, the current status and challenges of target amplification-free CRISPR/Cas-based detection are first summarised, followed by highlighting the four main strategies to promote the performance of target amplification-free CRISPR/Cas-based technology. The authors also discuss future perspectives that will contribute to developing more efficient amplification-free CRISPR/Cas detection systems.
• Genome Editing and Fatty Liver. In this review, authors in the US discuss currently non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) models developed using CRISPR-Cas9 technology. The authors also discuss variations of CRISPR technology including prime and base editors to replicate genetic topographies linked specifically to ALD and NAFLD.
• Genome Editing in Dyslipidemia and Atherosclerosis. Authors in Germany review the latest state of genome editing in translational research of dyslipidemia and atherosclerosis. They highlight recent progress in therapeutic development for familial dyslipidemia by genome editing, and also point to the challenges in maximising efficacy and minimising safety issues related to the once-and-done therapy focusing on CRISPR-Cas systems. Finally, the authors share an outlook on the potential gene targets prioritised by large-scale genetic studies of cardiovascular diseases and genome editing in precision medicine of dyslipidemia and atherosclerosis.