DNA Circling the Nanopore Drain May Improve Sequencing Flow

At the nanoscale, a clogged drain wont clear be cleared with a plunger or a snake or Drano, for that matter. But application of an external force can help, provided the nanoscale plumbing has the right surface, an irregular surface, or rather, a surface that is irregular in the right way. Graphene membranes that contain nanopores are being evaluated for use in DNA sorting and sequencing applications. Often, when these membranes are fabricated, they end up with surface-step defects, tiny terraced regions that would require any biomolecules sliding over the surface to occasionally step up, or down, to keep traveling along a given path—which could, for example, lead to a nanopore sensor. Rather than try to eliminate these defects, scientists at the University of Illinois at Urbana-Champaign (UIUC) resolved to find a way to work with them. Using all-atom molecular dynamics, the scientists demonstrated that DNA physisorbed to a graphene surface moved much faster down a step defect than up, and even faster along the defect edge, regardless of whether the motion was produced by a mechanical force or a solvent flow. These findings were surprising, not the least because gravity at the nanoscale is negligible, which means that moving a biomolecule a step up shouldn’t require any more energy than moving the same biomolecule a step down. While puzzling, this difference is interesting. It suggests that architectures are possible that could overcome the strong physisorption of DNA onto graphene, which has so far severely limited the sensing and sequencing applications of graphene nanopores. Initially, the UIUC scientists, physics professor Aleksei Aksimentiev, PhD, and graduate student Manish Shankla, thought they could use concentric defect patterns around the pores to force biomolecules down. The scientists’ simulations, however, showed that biomolecules tended to congregate along the edges of the steps. That was when the scientists had a revelation: A defect with edges spiraling into a pore, combined with an applied directional force, would give a biomolecule no other option than to go into the pore—as though circling down a drain.

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Twist Bioscience Expands Express Genes Rapid Synthesis Service

Twist Bioscience Corporation | January 30, 2024

Twist Bioscience Corporation a company enabling customers to succeed through its offering of high-quality synthetic DNA using its silicon platform, today announced the expansion of Twist Express Genes, a new leading gene synthesis service with an order to shipping turnaround starting at five business days1, to include larger DNA preparations up to 1 milligram. The Express Genes offering, initially launched in November 2023, now extends to larger midiprep (10μg to 100 μg) and maxiprep (100μg to 1mg) DNA preparations. As with Twist standard speed Clonal Genes, all Twist Express Genes are NGS-verified as clonally perfect. “Since the initial launch of our Express Genes service in November, we have received positive and enthusiastic feedback from existing customers on our consistent and rapid turnaround time. By expanding Express Genes to include midiprep and maxiprep, we can now offer rapid gene synthesis at all gene prep scales, enabling large scale experimentation for pharmaceutical, biotechnology, academic and industrial chemical researchers,” said Emily M. Leproust, Ph.D., CEO and co-founder of Twist Bioscience. “With the expanded offering of Twist Express Genes, more researchers can gain access to Twist genes fast and at scale, including those using alternative providers and those cloning their own genes. The ability to order and receive synthetic DNA fast and at scale means more time for cutting-edge research, more make-test-learn cycles, and an accelerated journey to game-changing discoveries.” Twist leverages its ability to miniaturize the chemical reaction to create DNA using its silicon-based DNA synthesis platform along with expertise, software, optimized processes and the expanded layout of its Wilsonville facility to deliver Clonal Genes and Gene Fragments at scale and with rapid turnaround times. Twist’s Express Genes are offered with dynamic pricing, which reflects market demand and manufacturing capacity in a responsive premium price. Customers are able to quickly and easily place orders for Express Genes through Twist’s ecommerce platform. Twist Express Genes Twist Express Genes are 0.3kb to 5.0kb in length. Due to scale enabled by Twist’s platform, orders of any size both small and large can be filled, and as with standard speed Twist Clonal Genes, Twist Express Genes are NGS sequence-verified as one hundred percent accurate. Twist Express Genes can be cloned into catalog vectors or custom vectors so that customers can move right to experimentation. They can also be shipped in customers’ preferred delivery formats, including tubes and plates. For more information and product specifications click here. Current turnaround times for some Twist Bioscience products Express Genes1 (50ng-10µg): starting at 5 business days, now for up to 10µg Standard Clonal Genes (50ng-10µg): starting at 10 business days Express Genes1 (10µg-1mg): starting at 8 business days Standard Clonal Genes (10µg-1mg): starting at 13 business days 1 Express Clonal Genes ship in 5-7 business days. DNA prep sizes including 10 μg - 100 μg, and 100 μg - 1 mg may incur an additional 3-5 days for synthesis. Orders placed outside of the US will incur additional delivery turnaround time. Express Genes orders that require new custom vector onboarding will incur an additional 1-2 weeks for processing. About Twist Bioscience Corporation Twist Bioscience is a leading and rapidly growing synthetic biology and genomics company that has developed a disruptive DNA synthesis platform to industrialize the engineering of biology. The core of the platform is a proprietary technology that pioneers a new method of manufacturing synthetic DNA by “writing” DNA on a silicon chip. Twist is leveraging its unique technology to manufacture a broad range of synthetic DNA-based products, including synthetic genes, tools for next-generation sequencing (NGS) preparation, and antibody libraries for drug discovery and development. Twist is also pursuing longer-term opportunities in digital data storage in DNA and biologics drug discovery. Twist makes products for use across many industries including healthcare, industrial chemicals, agriculture and academic research.

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Cell and Gene Therapy

Solvias to Perform Release Testing on World's First CRISPR-based Gene-Editing Therapy

Solvias | January 23, 2024

Solvias, a global provider of chemistry, manufacturing, and control (CMC) analytics, announced that it will perform analytical release testing services on the world's first CRISPR/Cas9 genome-edited cell therapy. The company has signed a long-term agreement with Vertex Pharmaceuticals for CASGEVY™ (exagamglogene autotemcel or exa-cel) which received U.S. Food & Drug Administration (FDA) approval for the treatment of sickle cell disease (SCD) in patients 12 years and older with recurrent vaso-occlusive crises. Solvias and Vertex Pharmaceuticals have worked together for several years to develop and validate test methods that are critical for the final release of patients' own edited cells, so that they can be delivered back to patients. The companies' collaboration included establishing the testing methods that will be scaled for commercializing CASGEVY. Solvias also has invested significantly in preparing one of its global facilities to support the commercial release work for this transformative therapy. Archie Cullen, Chief Executive Officer, Solvias, stated "Solvias is honored to be playing a critical role in delivering this breakthrough therapy to patients. Our decades of experience offering comprehensive GMP analytical services uniquely positions us to partner with companies in bringing their therapies to market. This collaboration highlights our deep scientific knowledge and creative solutions serving to advance even the most cutting-edge therapies." In addition to gaining FDA approval, CASGEVY recently received a positive opinion from the European Medicines Agency's (EMA's) Committee for Medicinal Products for Human Use for conditional approval of the treatment of severe SCD and transfusion-dependent beta thalassemia (TDT). About Solvias Solvias is a global provider of chemistry, manufacturing, and control (CMC) analytics to the pharmaceutical, biotech, material science, and cosmetic industries. Its team of scientists and regulatory experts have years of experience in small molecules, biologics, and cell and gene therapies. The company offers comprehensive solutions from raw materials to drug products to final release testing, as well as API development and manufacturing for small molecules. Headquartered near Basel, Switzerland, Solvias operates five facilities to the highest standards and in accordance with ISO, GMP, GLP and FDA regulations.

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Jnana Therapeutics Announces Positive Clinical Proof of Concept Achieved with JNT-517, a Potential First-in-Class Oral Treatment for PKU

Jnana Therapeutics, Inc. | February 02, 2024

Jnana Therapeutics, a clinical-stage biotechnology company leveraging its next-generation chemoproteomics platform to discover medicines for challenging-to-drug targets, today announced positive, statistically significant interim results from its ongoing clinical study of JNT-517 in individuals with phenylketonuria (PKU). JNT-517, a small molecule inhibitor of the phenylalanine (Phe) transporter SLC6A19, is being evaluated as a potential first-in-class oral treatment for PKU across all ages and genotypes. On the basis of these positive interim results, Jnana has adapted the Phase 1b trial design to support the potential for accelerated progression of JNT-517. “There is an urgent need for an oral, safe, and efficacious therapy for the more than 60% of individuals with PKU not currently on therapy. Across the spectrum of mild to severe disease, our results demonstrate a robust, sustained reduction in blood Phe levels, the registrational endpoint for PKU, giving us high confidence in the path forward for JNT-517,” said George Vratsanos, M.D., Chief Medical Officer and Head of R&D at Jnana Therapeutics. “We are also encouraged by this validation of the power of our RAPID platform to discover small molecules with compelling clinical benefit against challenging-to-drug targets.” JNT-517 is being studied in a randomized, double-blind, placebo-controlled trial in individuals with mild to severe PKU. Following a 28-day screening period focused predominantly on ensuring an average blood Phe level of >600µM, study participants were randomized with no run-in period to 75mg of JNT-517 twice daily (BID) or placebo. The planned interim analysis was based on 13 participants, eight dosed with JNT-517 and five dosed with placebo over 28 days, and demonstrated the following results JNT-517 led to a statistically significant (p=0.0019 vs. placebo) mean blood Phe reduction from baseline of 51%, measured per-protocol at day 28. A high response rate was seen where seven of eight (88%) treated participants achieved >30% reduction in blood Phe from baseline; five of eight (63%) achieved >45% reduction; and two of eight (25%) achieved >65% reduction. A robust response was seen across participants treated with JNT-517 irrespective of baseline blood Phe levels, which ranged from 593µM to 1,526µM with a mean of 1,124µM. A rapid onset of effect was observed with significant blood Phe reduction achieved within seven days after commencing dosing, which was sustained through the full 28 days of dosing. JNT-517 was safe and well tolerated with no serious adverse events and no clinically significant changes in laboratory parameters, consistent with the safety profile demonstrated in the Phase 1a healthy volunteer study. "JNT-517 represents a completely new therapeutic approach that could transform the current treatment paradigm in PKU, in particular for individuals with severe, or classical, PKU where there is the highest unmet medical need,” said Cary O. Harding, M.D., study investigator and Professor of Molecular and Medical Genetics at Oregon Health and Science University School of Medicine. “I am encouraged by the clinical results to date and look forward to working with Jnana and the PKU community to continue to advance this program.” Based on these interim results, Jnana has adapted the protocol of the ongoing trial to include dose exploration. Jnana expects topline data from the second dose cohort in mid-2024 and plans to submit full data from the two dose cohorts for presentation at a scientific meeting in the second half of 2024. Jnana anticipates the company will engage regulators in the second half of 2024 and seek to advance JNT-517 directly into a pivotal Phase 3 study in the first half of 2025. JNT-517 Phase 1b Clinical Trial The ongoing clinical program includes a randomized, double-blind, placebo-controlled trial evaluating the safety, tolerability, pharmacokinetics, and effect on blood and urinary Phe of JNT-517 dosed over a four-week period in individuals diagnosed with PKU. The study dosed its first participant with PKU in August 2023 and is enrolling individuals aged 18 to 65 at clinical sites in the United States and Australia. For more information about the study, please see clinicaltrials.gov (NCT05781399). About JNT-517 JNT-517 is a selective small molecule inhibitor of the Phe transporter SLC6A19 that has the potential to be a first-in-class oral therapy used to treat any person with PKU, regardless of age or genotype. JNT-517 acts at a novel, cryptic allosteric site to block kidney reabsorption of Phe and offers a promising new approach to reduce blood Phe levels. The U.S. Food and Drug Administration granted JNT-517 Rare Pediatric Disease Designation in late 2022. About PKU PKU is a rare inherited metabolic disorder caused by a deficiency of the enzyme phenylalanine hydroxylase (PAH). This enzyme is required for the breakdown of phenylalanine (Phe), an amino acid found in all protein-containing foods. When PAH is deficient or defective, Phe accumulates to abnormally high levels in the blood. If left untreated, toxic levels of Phe in the blood can result in progressive and severe neurological impairment and neuropsychological complications. The SLC transporter SLC6A19 is responsible for kidney reabsorption of Phe back into the bloodstream, and the inhibition of SLC6A19 offers a novel, oral approach for the treatment of PKU by facilitating urinary excretion of excess Phe. About Jnana Therapeutics Jnana Therapeutics is a clinical-stage biotechnology company leveraging its next-generation RAPID chemoproteomics platform to discover medicines for highly validated, challenging-to-drug targets to treat diseases with high unmet needs. Jnana is focused on developing first- and best-in-class therapies to treat a wide range of diseases, including rare diseases and immune-mediated diseases. Jnana’s wholly owned lead program, JNT-517, which targets an allosteric site on the phenylalanine transporter SLC6A19, is a potential first-in-class oral approach for the treatment of PKU, a rare genetic metabolic disease. Located in Boston, Jnana brings together scientific leaders in small molecule drug discovery and development, a highly experienced management team, and the backing of leading life science investors Bain Capital Life Sciences, RA Capital Management, Polaris Partners, Versant Ventures, Avalon Ventures, Pfizer Ventures, and AbbVie Ventures.

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