The Needle. Issue #5


Welcome to the latest issue of the Needle, a newsletter from Haystack Science on preclinical biotech.

This week, we take a look at all the action at the American Society of Gene and Cell Therapy Annual Meeting in New Orleans and announcements around next-generation DNA and RNA editing technologies, with one base editing therapy for an ultrarare disease grabbing the headlines. It was a slow week for industry news, but there were a notable number of deals and financings for companies out of South Korea.

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Last week’s ASGCT 2025 provided a stark contrast between excitement around DNA- and RNA-editing platforms and commercial interest in traditional gene replacement and cell therapy. Over the past few months, Pfizer decided to stop the commercialization of its hemophilia B gene therapy Beqvez, lentiviral gene therapy flagship Bluebird Bio agreed to acquisition by private-equity firms Carlyle and SK Capital Partners, and earlier this month, Vertex announced its was discontinuing its gene-therapy programs.The remarkable clinical progress achieved with base editing modalities over the past year was highlighted in an ASGCT keynote by Kiran Musunuru of the University of Pennsylvania on the ultra-rare condition carbamoyl-phosphate synthetase 1 (CPS1) deficiency. The fact that the UPenn group were able to design, preclinically validate and bring the treatment to a child in just 7 months is staggering:

Writing in the New England Journal of Medicine, the team led by Musunuru and Rebecca Ahrens-Nicklas describe the development of a personalized base-editing therapy with guide RNAs designed to remove the UGA stop codon in a neonate diagnosed with a Q335X variant of CPS1. Using an adenine base-editor, the team designed a bespoke, corrective therapy delivered in vivo using lipid nanoparticles (LNPs) comprising an ionizable amino lipid (ALC-0307), cholesterol, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), and a PEG lipid (ALC-0159).

After preclinical validation in cell lines, mice and non-human primates, the authors administered two intravenous doses of the base editor, dubbed ‘k-abe’ — 0.1 mg/kg at seven months of age and 0.3 mg/kg one month later. Following treatment, the patient tolerated increased dietary protein and showed a reduced need for ammonia-scavenging medication, with no serious adverse events. Long-term clinical outcomes and safety remain under evaluation.

One of the most striking features of the study is the speed of therapy development—from diagnosis to treatment in a mere seven months, during which the team had to create cell and mouse models of the disease, screen various base editors with guide RNAs covering the site of the mutation to identify the most efficient approach, carry out toxicological assays in non-human primates, and obtain FDA regulatory approval to treat the child. The workflow reported represents a blueprint for rapid development of customized gene-editing therapies for patients with ultra-rare variants and provides one of the first glimpses of a coming era in advanced therapeutics.

The FDA has taken a very progressive attitude regarding N-of-1 therapies that involve platform technologies such as base editing. An accompanying Editorial in the NEJM, authored by Peter Marks, former Director of the FDA's Center for Biologics Evaluation and Research, elaborates on the need for a regulatory approach that takes advantage of the data from the elements that remain consistent from one therapeutic product to the next, while allowing the customization required for individual patients — in the case of base editors, a short sequence of guide RNA.

Of course, despite the openness of regulatory authorities, several hurdles remain before bespoke DNA and RNA editing therapies becomes a reality. Among them, manufacturing, scalability and distribution are particularly problematic, and represent the biggest challenges for big pharma to address before widespread adoption of such approaches. Also, existing lipid nanoparticles preferentially travel to the liver. Targeting other organs remains a huge challenge for the field so ultrarare liver disease will remain the option in reach for base editing in the near term. But despite these concerns, we think that the report by Musunuru and his colleagues is a milestone in the development of genetic medicines and underscores the potential of gene-editing approaches to deliver bespoke cures for ultra-rare diseases.

Papers: Best of the rest

Target biology

Radiation-induced amphiregulin drives tumour metastasis | Nature

Inhibition of ENT1 relieves intracellular adenosine-mediated T cell suppression in cancer | Nature Immunology

TMEM219 signaling promotes intestinal stem cell death and exacerbates colitis | JCI

Microglial TMEM119 binds to amyloid-β to promote its clearance in an Aβ-depositing mouse model of Alzheimer’s disease: Immunity

A prolactin-targeting antibody to prevent stress-induced peripheral nociceptor sensitization and female postoperative pain | PNAS

Asparagine endopeptidase cleaves apolipoprotein A1 and accelerates pathogenesis of atherosclerosis | JCI

CHD1 loss reprograms SREBP2-driven cholesterol synthesis to fuel androgen-responsive growth and castration resistance in SPOP-mutated prostate tumors | Nature Cancer

Therapeutic modalities

Rapid closure and hemostasis of ruptured soft tissues using a modified human tropoelastin-based sealant in preclinical models | Science Translational Medicine

Programmable gene insertion in human cells with a laboratory-evolved CRISPR-associated transposase | Science

Computationally designed bicyclic peptide inhibitor targeting ICOS/ICOS-ligand protein–protein interaction |Chem Biol Drug Design

Self-assembling protein nanoparticles for cytosolic delivery of nucleic acids and proteins | Nature Biotechnology

Multiplex imaging of amyloid-β plaques dynamics in living brains with quinoline-malononitrile-based probes | Nature Biomedical Engineering

Preclinical goings on

Apart from the groundbreaking work of Musunuru et al., several startups also showcased preclinical data at ASGCT on other new non-Cas9 CRISPR DNA- and RNA-editing platforms (abstracts can be searched here).

Startup (location) Preclinical data presented
Huidagene (Shanghai, China) A new RNA editing mechanism via Cas13 for MECP2 duplication syndrome
Yap Therapeutics (Houston, TX) AAV9 delivering three shRNAs targeting Hippo component Salvador-1 for activating cardiomyocyte repair in ischemic heart failure (Search for Leach)
Arbor Biotechnologies (Cambridge, MA) Engineered Cas12i2 type V nuclease with low-off target rate disrupts UBE3A-ATS antisense imprinting mechanism of UBE3A in Angelman’s syndrome patient-derived iPSC neurons
Precision Biosciences (Durham, NC) AAVrh.74-delivered homing endonuclease ARCUS-mediated excision of exons 45-55 of human dystrophin gene leads to restoration of dystrophin protein for 9 months in mdx model
AIRNA (Cambridge, MA) GalNAc-conjugated antisense oligonucletide-mediated recruitment of endogenous ADAR achieves >50% editing of SERPINA1 mRNA in a mouse model of alpha 1 antitrypsin disease
Nanoscope Therapeutics (Bedford, TX) Safety and efficacy of intravitreally injected AAV2 ambient light activatable multi-characteristic opsin targeting inner retinal neurons in non human primate model
Helex (New York, NY) Kidney-trophic lipid nanoparticle delivery of CRISPR-Cas9 to target a mutation-agnostic regulatory sequence in PKD1 for autosomal dominant polycystic kidney disease

Although several ASGCT presentations focused on circular RNA-encoded CARs transduced into T cells (Sail Biomedicines and Strand Therapeutics), the emphasis clearly shifted away from preclinical data around conventional AAV gene therapy supplementation to an intense focus on solving AAV commercial production issues, lowering empty capsid content in gene therapy production batches and reducing COGS.

NY-based startup Helex named among recipients of NIH Targeted Genome Editor Delivery (TARGETED) Phase 2 Challenge Awards

Rare Disease Priority Review Vouchers still bringing in >$150 million: Abeona Therapeutics

Optigo Biotherapeutics wins EyeAccelerator Award for long-lasting (6 months) anti-angiogenic bispecific antibodies and Fc-fusion proteins with an albumin- or hyaluronan-anchoring domain, opening up long-duration intravitreal injections for the eye

Preclinical funding

Date Company (location) Amount (millions) Funding type (lead investors) Therapeutic (lead) focus
May 9, 2025 Commit Biologics (Aarhus, Denmark) €16 Seed (Bioqube Ventures and Novo Holdings) Bispecific complement engaging (BiCE) single-domain antibody inhibitors of complement protein C1q in autoimmune disease
May 12, 2025 Abli Therapeutics (Atlanta, GA) ND Seed (Undisclosed) Small molecule and antibody kinase inhibitors of c-Abl in neurodegenerative diseases
May 13, 2025 Somite AI (Boston, MA) $47 Series A (Khosla) ML foundation model to predict factors for differentiation of stem-cell-derived therapies with optimal purity, functionality, and scalability
May 13, 2025 Azafaros (Leiden, The Netherlands) $146 Series B (Forbion and Jeito Capital) Nizubaglustat, a brain-penetrant azasugar, dual inhibitor of ceramide glucosyltransferase and non-lysosomal glucosylceramidase in Niemann-Pick disease
May 19, 2025 Eascra Biotech (Boston, MA) $0.1 Grant (Mass Ventures) Biomimetic guanine-cytosine ‘Janus’ nanotubes for siRNA delivery
May 19, 2025 Massalia Therapeutics (Marseille, France) ND Seed (Landmark Bioventures) Mab against soluble angiogenic neoplastic fibrotic factor (SANF) in cancer-associated fibrosis

Preclinical deals

Date Type Payer (location) Payee (location) Upfront payment (millions) Milestones amount (millions) Total (up to millions) Therapeutic Lead Focus
May 6, 2025 R&D Collaboration BioCopy (Emmendingen, Germany) Biocytogen (Beijing, China) ND ND ND Discovery of fully human TCR-mimetic mAbs from Biocytogen’s transgenic mice against an undisclosed intracellular antigen
May 13, 2025 R&D Collaboration Eli Lilly (Indianapolis, IN) Rznomics (Seongnam, South Korea) ND ND 1,300 Transplicing group I intron ribozyme for RNA editing therapeutics in sensorineural hearing loss
May 15, 2025 R&D Collaboration Agilent (Santa Clara, CA) Ubix Therapeutics (South Korea) ND ND ND PROTACs and ADCs against BCR-Abl, SHP2, SOS1 and HPK1 in solid tumors

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Until next week,

Juan Carlos and Andy

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