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BioMed & MedTech · week of 21 September 2026

A Promising Lead

Week 39 — three stories that stop short of being the finished answer, on purpose. An AI-agent swarm surfaces a CRISPR-like DNA pattern nobody's characterized yet; a decade-long consortium builds the largest gene-activity map of the human prefrontal cortex, a resource rather than a result; and a phase 2 trial doesn't just report a response rate, it builds the biomarker case for which patients that response rate actually applies to.
This Week's Overview

Last week ended on old biology getting retooled into something new — a paralytic neurotoxin re-engineered to kill cancer cells, a bacterial pore protein turned into a four-in-one molecular sensor. This week sits a step earlier in that same pipeline: not repurposing something already understood, but producing the raw material — the lead, the map, the biomarker — that a future tool or trial will eventually be built from.

A lead, a map, a biomarker

Anthropic's new AI-driven biology lab turned roughly 950 autonomous AI agents loose on a database of viral genomes and surfaced a repeated DNA pattern that structurally resembles a CRISPR array — intriguing, and honestly described by the company's own head of life sciences as "a promising lead," not a discovery. A consortium nearly a decade in the making built something closer to infrastructure than a single finding: the largest gene-activity map of the human prefrontal cortex yet assembled, spanning donors from infancy to age 108 and eight separate brain disorders, meant as a resource other studies compare against rather than a standalone result. And a phase 2 trial of the CD47-blocking drug evorpacept in HER2-positive gastric cancer didn't stop at a response-rate win — it built the biomarker case for exactly which patients that win applies to, the groundwork a phase 3 trial needs before it can even start.

And what's left over

Below the three focus stories, Also This Week collects the rest: two new catalogs of the regulatory DNA behind human-specific anatomy, a second AI system this week finding structure in genomic regions nobody had gotten around to labeling — and, strikingly, also centered on a reverse-transcriptase gene of unknown function, the same raw material as this week's lead focus story — three more angles on cancer biology, and the search for the next targets in metabolic and cardiovascular disease.

Contents

Focus Topics

  1. AI agents find a pattern nobody's named yet
  2. The biggest map of a brain region ever made
  3. A checkpoint blocker earns its biomarker

Also This Week

  1. Cataloguing the regulatory genome
  2. AI finds what nobody had labeled
  3. Cancer biology, three more angles
  4. The next targets in metabolic and cardiovascular disease

Test Yourself

Read the newsletter and you'll be able to answer these.
  1. What did Anthropic's AI agents actually find, and roughly how did they find it? ↷
    Show answer
    Surveying a database of viral genomes for proteins that work alongside reverse-transcriptase enzymes, roughly 950 autonomous AI agents spent more than 21 hours self-directedly exploring billions of proteins and, while examining the DNA around a reverse-transcriptase gene in a giant virus, repeatedly spotted the same short DNA sequence — a repeated pattern structurally similar to a CRISPR array.
  2. What's the key caveat on this finding, in Anthropic's own framing? ↷
    Show answer
    There's no evidence yet that the repeats carry out a CRISPR-like function, and no known DNA-cutting enzyme partnered with them has been identified. Eric Kauderer-Abrams, Anthropic's head of life sciences, called it "a promising lead," adding that fully characterizing it and developing it into an actual tool is the hard part still ahead.
  3. What's the scale of the new prefrontal cortex atlas — donors, cells, and conditions covered? ↷
    Show answer
    Single-cell RNA sequencing across more than 6.3 million individual brain cells from almost 1,500 donors, ranging from infants to a 108-year-old, of diverse ancestries. Donors included neurotypical controls plus people diagnosed with one of eight brain disorders: Alzheimer's disease, dementia with Lewy bodies, Parkinson's disease, vascular dementia, tauopathy, frontotemporal dementia, schizophrenia, or bipolar disorder.
  4. What three phases of prefrontal cortex development did the atlas's foundational lifespan study identify? ↷
    Show answer
    A rapid remodeling phase during early life, a stable period from around age 24 onward, and a second remodeling phase beginning around age 65 — with early-life changes linked to developmental gene activity and late-life changes linked to immune activity, stress responses, and circadian-rhythm genes.
  5. How is evorpacept designed differently from earlier anti-CD47 drugs, and why does that matter? ↷
    Show answer
    It's an engineered fusion of SIRPα's D1 domain with a deliberately inactive Fc domain from human IgG1. Earlier anti-CD47 drugs like magrolimab caused off-tumor toxicity because CD47 is also expressed on healthy cells (like blood cells); the inactive Fc domain avoids that toxicity, but means evorpacept has no independent tumor-killing activity of its own — it only works paired with an active antibody like trastuzumab.
  6. In the ASPEN-06 phase 2 trial's intent-to-treat population, what were the headline objective response rates? ↷
    Show answer
    B. 127 patients were randomized (63 to evorpacept plus TRP, 64 to TRP alone); the intent-to-treat ORR was 40.3% (95% CI 28.1–49.3) versus 26.6% (95% CI 16.3–39.1). Answer A is the later, biomarker-selected subgroup result, not the full-population number.
  7. What did the CD47-biomarker analysis reveal about which patients benefited most, and which patients saw no benefit at all? ↷
    Show answer
    In patients with confirmed retained HER2-positive disease and high tumor CD47 expression (≥5% IHC3+ staining, n=48), ORR rose to 63.6% with evorpacept plus TRP versus 23.1% with TRP alone, with a longer median duration of response (25.5 vs 8.4 months) and a lower risk of progression (PFS hazard ratio 0.38). Patients who had lost HER2 expression saw no benefit from adding evorpacept, regardless of their CD47 status.
  8. Was the addition of evorpacept safe? What did the adverse-event data show? ↷
    Show answer
    Treatment-emergent adverse events of any grade occurred in 100% of patients in both arms (expected for a four-drug chemo-antibody regimen), most commonly neutropenia, anemia and diarrhea, each modestly more frequent with evorpacept added. Discontinuation rates and febrile-neutropenia incidence were similar between arms, and the authors describe the added toxicity as manageable with standard supportive care — the first randomized trial, they note, to show both real clinical activity and a manageable safety profile for CD47–SIRPα inhibition.
  9. What did the MINERVA tool (covered in this week's "Also This Week") find in bacterial genomes, and how does it relate to this week's lead story? ↷
    Show answer
    Built by researchers at Arc Institute and Stanford, MINERVA predicts which positions in a genome structurally interact directly from sequence, without needing a known related gene family — aimed at the non-coding "blind spot" alignment-based methods miss. Scanning 150 bacterial genomes in about 100 minutes, it flagged tens of thousands of likely RNA-hairpin-forming regions, most previously unannotated, including a signal inside "UG27" reverse-transcriptase systems that produces DNA molecules of unknown function — a second AI system this week surfacing an uncharacterized nucleic-acid structure next to a reverse-transcriptase gene, the same raw material as Anthropic's find.

From Last Week's Issue — 2026-09-20

  1. What is VIPR, and what's different about how it recognizes DNA compared with modern CRISPR-Cas systems? ↷
    Show answer
    VIPR (Viral Interference Programmable Repeat) is an ancestral RNA-guided DNA-recognition system identified as CRISPR-Cas's likely evolutionary predecessor. Instead of the straightforward contiguous base-pairing match modern CRISPR effectors use, VIPR recognizes DNA through a noncontiguous code — separated contact points arranged into a geometric triplex structure that only add up to a specific match when read together.
  2. What specifically makes a "xenocortical" mouse different from earlier approaches, like transplanting human organoids into newborn rat cortex? ↷
    Show answer
    The mouse is genetically engineered first to lack its own dorsal and medial pallium (neocortex and hippocampus) — an "apallial" mouse. The transplanted human cortical organoid then grows into that actual vacated anatomical space, rather than competing for room and connectivity with an intact, faster-maturing host cortex.
  3. What does GFH375 target that earlier KRAS-G12C-directed drugs did not? ↷
    Show answer
    Both the "ON" (GTP-bound) and "OFF" (GDP-bound) states of the KRAS G12D mutant protein specifically — a different, more common RAS mutation than G12C, occurring mainly in pancreatic cancer, colorectal cancer and non-small cell lung cancer.
  4. In the GFH375 phase 1 trial, what were the confirmed response rates in pancreatic and lung cancer? ↷
    Show answer
    35.1% ORR in pancreatic cancer (13/37 patients) and 35.7% ORR in non-small cell lung cancer (5/14), in 74 heavily pretreated patients with advanced solid tumors who had already exhausted other options.

AI agents find a pattern nobody's named yet

Nature News, 25 September 2026

Anthropic has launched a biology "wet lab" — a research group where human scientists and AI agents work side by side to design and run experiments. This week the company announced one of the team's first finds: a peculiar, repeated pattern of DNA in the genomes of several giant viruses, structurally reminiscent of the arrays that power microbial CRISPR immune systems. It hasn't determined what the pattern actually does.

The method is as much the story as the finding. Anthropic's researchers set roughly 950 autonomous AI agents — systems that often rely on large language models — loose on a database of DNA sequences encoding billions of proteins, directed to search for proteins that work alongside reverse-transcriptase enzymes. The agents explored self-directedly for more than 21 hours, discussing preliminary results and deciding on next steps among themselves. While examining the DNA surrounding a reverse-transcriptase gene in one giant virus, they spotted the same short sequence of DNA letters, repeated over and over.

Those repeats resemble what's inside a bacterial CRISPR array: multiple repeated chunks of DNA, separated by segments copied from viruses or other invaders, which RNA later uses to guide a partner enzyme to cut an intruder's genetic material. But that's where the resemblance currently ends — there's no evidence yet that this newly spotted repeat does anything similar, and no known DNA-slicing partner enzyme has been identified alongside it. "This is a promising lead," said Eric Kauderer-Abrams, Anthropic's head of life sciences. "What's hard is to then go and completely characterize it, understand its function, and develop it into an interesting tool."

Kauderer-Abrams also pushed back on reading this as AI replacing biologists the way AI-generated proofs have unsettled parts of mathematics. Biology, he said, "requires actually running experiments in the physical world" — the agents can search and flag, but a human still has to go characterize what's actually there. The result was posted as a preprint on alphaXiv, not yet peer reviewed.

Why it matters

The headline isn't that this specific repeat will become the next gene-editing tool — it may not. It's that a swarm of AI agents, working self-directedly across billions of sequences and comparing notes with each other, surfaced a genuinely novel structural lead in genomic territory that's been public for years without anyone noticing it. That's a new way of searching, whatever this particular lead turns out to be.

The biggest map of a brain region ever made

Nature News, 23 September 2026

Researchers have produced the largest map to date of gene activity in the human prefrontal cortex — the region supporting planning, decision-making, and behavioral and emotional regulation. The work, published as a collection of eight studies including three in Nature, draws on single-cell RNA sequencing across more than 6.3 million individual brain cells from tissue donated by nearly 1,500 people after death. "The scale of this project and the amount of work required to assemble it are genuinely impressive," says Zhichao Miao, a computational biologist at the Guangzhou National Laboratory who wasn't involved in the work.

The project, run by the NIH-funded PsychAD Consortium, began in 2019. Panos Roussos, director of the Center for Disease Neurogenomics at Mount Sinai's Icahn School of Medicine and a co-author on all eight papers, says the group deliberately focused on one region studied consistently rather than spreading thin across many: donors ranged from infants to a 108-year-old, spanned diverse ancestries, and included both neurotypical controls and people diagnosed with one of eight brain disorders — Alzheimer's disease, dementia with Lewy bodies, Parkinson's disease, vascular dementia, tauopathy, frontotemporal dementia, schizophrenia, and bipolar disorder. "Studying the same region under different conditions enables more consistent comparisons and helps connect our results to existing genetic and molecular studies," Roussos says.

THREE PHASES OF PREFRONTAL CORTEX DEVELOPMENT Rapid remodeling < 1 – ~24 yrs Stability ~24 – ~65 yrs Second remodeling ~65+ yrs Early-life changes linked to developmental gene activity; late-life changes linked to immune activity, stress responses and circadian-rhythm genes.
Own diagram, based on the foundational lifespan study's reported developmental phases.

A foundational study within the collection tracked how the dorsolateral prefrontal cortex changes across a lifespan, using healthy brains from people under one year old to age 97. It identified three distinct phases: rapid remodeling during early life, stability from roughly age 24 onward, and a second remodeling phase beginning around age 65 — with different cell types showing distinct gene-activity patterns in each: developmental signals early on, and shifts tied to immune activity, stress responses and circadian rhythms late in life. "This is an important window into brain disease," Roussos says, "but additional regions will be needed to understand the full picture."

Why it matters

This atlas doesn't itself explain what causes Alzheimer's or schizophrenia — that's not what it's for. What it provides is a shared reference: the same brain region, the same techniques, the same consortium, spanning normal aging and eight separate disorders at once. Future studies chasing a specific disease mechanism now have a real baseline to compare against, instead of stitching one together from incompatible smaller datasets.

A checkpoint blocker earns its biomarker

Nature Medicine, 25 September 2026 — ASPEN-06 trial (NCT05002127)

CD47 is a "don't eat me" signal — a checkpoint protein overexpressed on many tumor cells that blocks macrophages from attacking them, but also expressed on healthy cells throughout the body, which is exactly why earlier anti-CD47 drugs ran into trouble: block CD47 broadly enough to help against a tumor, and you also expose healthy blood cells to the same attack. Evorpacept was engineered around that trade-off. It fuses the D1 domain of SIRPα (CD47's natural binding partner) to a deliberately inactive Fc domain, stripped of the antibody machinery that caused off-tumor toxicity in earlier drugs like magrolimab. The cost of that fix: evorpacept has no independent tumor-killing activity of its own. It only works paired with an active, tumor-targeting antibody — here, trastuzumab.

The phase 2 portion of the ASPEN-06 trial, an international, randomized phase 2/3 study, tested that pairing in 127 patients with HER2-positive advanced or metastatic gastric or gastroesophageal-junction cancer that had progressed on prior anti-HER2 treatment — a second- or third-line setting, across 49 institutions in ten countries. Patients received either evorpacept added to trastuzumab, ramucirumab and paclitaxel (evo+TRP, n=63) or that same three-drug regimen alone (TRP, n=64).

In the intent-to-treat population, the objective response rate was 40.3% with evorpacept added, versus 26.6% for TRP alone. The real story, though, is what a follow-up biomarker analysis found underneath that topline number: restricting to patients with both confirmed retained HER2-positive disease and high tumor CD47 expression (≥5% of cells staining strongly positive, n=48), the response rate climbed to 63.6% versus 23.1%, median duration of response nearly tripled (25.5 vs. 8.4 months), and the risk of disease progression roughly halved (hazard ratio 0.38). Patients who had lost HER2 expression saw no benefit from evorpacept at all, regardless of their CD47 status — the biomarker wasn't incidental, it was load-bearing.

ASPEN-06 — OBJECTIVE RESPONSE RATE, EVO+TRP VS TRP ALONE Full trial population (ITT, n=127) 40.3% (evo+TRP) 26.6% (TRP alone) Retained HER2+ & CD47-high subgroup (n=48) 63.6% (evo+TRP) 23.1% (TRP alone) CD47-high subgroup also showed longer duration of response (25.5 vs 8.4 months) and lower progression risk (HR 0.38).
Own diagram, from ASPEN-06's reported intent-to-treat and biomarker-subgroup efficacy data.

Safety was consistent with what a four-drug chemo-antibody regimen would predict: treatment-emergent adverse events of any grade occurred in 100% of patients in both arms, most commonly neutropenia (69.8% vs. 55.6%), anemia (58.7% vs. 38.1%) and diarrhea (41.3% vs. 36.5%), each modestly more frequent with evorpacept added. Discontinuation rates and the incidence of febrile neutropenia were similar between arms. The authors describe this as the first randomized study to demonstrate both real clinical activity and a manageable safety profile for CD47–SIRPα inhibition — a combination that has tripped up other drugs in this class before.

Why it matters

Earlier anti-CD47 drugs got stuck on a hard trade-off: block CD47 well enough to matter, and you also hit healthy cells hard enough to matter. Evorpacept's inactive-Fc design sidesteps that by giving up independent potency — and this trial's real contribution is showing that trade works when you also select for the right patients by biomarker. That's not a finished drug yet. It's the case a phase 3 trial can now actually be built on.

Also This Week

Cataloguing the regulatory genome

Two papers this week catalog the regulatory DNA behind traits that make humans look like humans. A study on the gene-regulatory evolution of the human skeleton finds that variants in genes producing extracellular matrix molecules — not the structural genes themselves — could have enabled the skeletal adaptations that distinguish humans from other great apes, using massively parallel reporter assays and human–ape hybrid skeletal cells to test candidate regulatory elements directly. A separate atlas of cell types and regulatory elements underlying human facial diversity combines single-cell transcriptomics, spatial transcriptomics and chromatin accessibility maps of the developing human craniofacial region, aiming to explain both normal facial variation and craniofacial pathology from the same regulatory map. Neither paper claims to have found "the" gene for either trait — both are building the reference catalog a mechanistic answer would eventually be found in.

AI finds what nobody had labeled

Two more AI systems this week went looking in genomic territory that's easy to skip past. AlphaFold's database expanded to include protein complexes from common viruses, predictions the researchers behind it say could aid pandemic preparedness — though, like any AlphaFold prediction, they'll need experimental confirmation before anyone treats them as ground truth. More strikingly, this week's BioByte digest covers MINERVA, a tool built by researchers at Arc Institute and Stanford that predicts which positions in a genome structurally interact directly from sequence — without needing a known related gene family to align against, the blind spot that alignment-based methods hit hardest in non-coding DNA and RNA. Scanning 150 bacterial genomes in about 100 minutes, MINERVA flagged 57,787 likely RNA-hairpin-forming regions, nearly 70% of them outside any existing annotation. One signal, inside "UG27" reverse-transcriptase systems embedded in dormant bacterial-virus genomes, was validated in the lab: expressed in E. coli, five UG27 systems each produced short single-stranded DNA molecules mapping precisely to the predicted RNA hairpins, and disabling the reverse transcriptase eliminated the product. What those DNA molecules are actually for is still unknown — a second, independently run AI system this week surfacing an uncharacterized nucleic-acid structure next to a reverse-transcriptase gene, the same raw shape as this issue's lead story.

Cancer biology, three more angles

Pancreatic cancer that's metastasized to the liver was found to reprogram the liver's own hepatocytes into supplying serine, an amino acid the tumor cells can't synthesize on their own once they lack the necessary enzyme — a host-tissue hijack that promotes the metastasis's growth and survival in foreign territory. A separate mechanistic study identifies ZMYND8 as a brake on CD8+ T cell activity: it suppresses IL-2 receptor signalling by blocking a transcriptional activator needed to switch the receptor gene on, enforcing the "terminal exhaustion" state that lets tumors and chronic infections evade a sustained immune response — deleting ZMYND8 pushed T cells toward a more effector-like state and markedly improved both antiviral and antitumor immunity in the studied models, making it a new checkpoint-adjacent target. And Nature Cancer's new review series on next-generation cancer therapeutics takes stock of where the field's newer therapeutic approaches actually stand against the existing clinical landscape, rather than against each other in isolation.

The next targets in metabolic and cardiovascular disease

Two pieces this week look past today's best available drugs toward what comes next. Some patients see no meaningful benefit from potent GLP-1 anti-obesity drugs at all, and researchers are now specifically chasing why — understanding non-response could point toward combination therapies or genuinely personalized weight-loss regimens, rather than one drug fitting everyone. And in cardiac disease, a newly characterized atypical G protein–coupled receptor signaling pathway is proposed as a fresh therapeutic target for cardiac fibrosis — the scarring process that stiffens heart tissue after injury and drives progression toward heart failure, and one current drugs don't treat directly.