The biotechnology firm BrainChild Bio has raised $116 million in series A funding. The company, which launched in 2023 with seed funding from Seattle Children’s Hospital, wants to take chimeric antigen receptor T-cell (CAR-T) therapies into the central nervous system to fight solid tumors.
Its lead candidate is now going into a Phase 2 clinical trial for treating a pediatric brain cancer. But while the company says it is “kids first,” it also has plans to expand into adult indications, including brain metastases.
The science behind BrainChild comes from the work of Michael Jensen, his team at Seattle Children’s Hospital, and the hospital’s drug development arm, Seattle Children’s Therapeutics. Jensen, who is now BrainChild’s chief scientific officer, previously cofounded the immunotherapy firms Umoja Biopharma and Juno Therapeutics, the latter of which Celgene acquired in 2018.
Jensen says he has long had an interest in using CAR-T therapy to tackle solid cancers in children, especially brain cancers. At Seattle Children’s, he was able to perform research to understand the pathways behind these cancers and develop approaches to treat them.
Steven Brugger, BrainChild Bio’s CEO (left) and Michael Jensen, BrainChild Bio’s scientific founder Credit:
BrainChild Bio
Jensen says that as the team started investigating the delivery of CAR-T therapies directly into the cerebrospinal fluid, they were able to achieve repetitive dosing to the tumor bed, with the CAR-T therapy acting more like a small-molecule drug with predictable pharmacokinetics. What’s more, with dosing directly into the brain, the team did not see the toxicity syndromes that the CAR-T field knows all too well.
When the CAR-T therapy is injected into the cerebrospinal fluid, Jensen says, the T cells flow to the tumor using chemotaxis and start attacking it from the outside in.
Working with sick children allowed the team to refine its approach and run a small trial involving an incurable cancer called diffuse intrinsic pontine glioma, or DIPG. Every few weeks, children with DIPG would visit the Seattle hospital for a 10 min infusion of a CAR-T therapy that targets the immune checkpoint protein B7-H3, which is highly expressed in DIPG. While the trial was designed primarily to test the feasibility and tolerability of the treatment, several of the participants survived much longer than expected (Nat. Med. 2025, DOI: 10.1038/s41591-024-03451-3).
BrainChild’s CEO is Steven Brugger, whose last role was CEO of the vaccine firm Affinivax. Brugger says he was winding down after Affinivax was bought by GSK when he got a call about a job at BrainChild. He says he’s learned a lot about CAR-T therapy since meeting Jensen, who is “now a dear friend.”
Brugger says the new financing, which was led by an undisclosed private family fund, will pay for a Phase 2 trial (NCT07680439) of the company’s B7-H3-targeting treatment, dubbed BCB-276. He says the results will be the basis of a future biologics license application to the US Food and Drug Administration.
BrainChild will also continue to develop BCB-214, a triple-valent CAR-T therapy that targets B7-H3, EGFR, IL-13Ralpha2 proteins. A phase 1 trial of BCB-214 as an adult glioblastoma treatment is planned for next year.
Jensen says it would be wrong to pigeonhole BrainChild as a glioma company or as focused only on pediatric cancers. For example, he and his fellow BrainChild scientists are also interested in treating cancers that spread to the brain from elsewhere in the body.
“I think Michael is a pioneer,” Brugger says. In a few years, when he next approaches funders, BrainChild “will be a very different company,” Brugger predicts.
Laura Howes is the Executive Editor for life sciences at C&EN.
