Caribou Biosciences, a biotech developing off-the-shelf cell therapies for blood cancers, said it will discontinue its pipeline and lay off employees – a move that reflects shifting investor appetite towards in vivo approaches.

Caribou is shelving further development activities for its two allogeneic CAR-T cell therapy programmes, vispa-cel for the treatment of relapsed or refractory (R/R) B cell non-Hodgkin lymphoma and CB-011 for the treatment of R/R multiple myeloma.

In line with the pipeline winddown, the company is implementing reductions to its workforce and initiating cost-cutting measures. As of February 2026, 97 people worked at the company full-time. While not disclosing how many employees will be cut, Caribou said the reductions would be “substantial”.

The biotech’s board is now seeking exit routes, including a merger, acquisition, business combination, or other deals that involve Caribou in its entirety or a transaction of assets.

In a statement on LinkedIn, CEO Rachel Haurwitz said: “Caribou’s story has taken a heartbreaking turn. This decision is not a loss of belief in our science, our clinical data, or what these programmes could mean for patients. It reflects the difficult reality that the current financing environment for allogeneic CAR-T cell therapies has made it impossible to secure the capital required to responsibly advance them.”

CAR T-cell therapy is a personalised type of immunotherapy that genetically reprogrammes a patient's own white blood cells to identify and destroy cancer cells. Caribou’s approach takes conventional ex-vivo CAR-T and uses CRISPR genome editing to turn donor T cells into a standardised, “off-the-shelf” product.

There is a plethora of approved CAR-T products, with Gilead’s Yescarta (axicabtagene ciloleucel) and Johnson & Johnson’s (J&J) Carvykti (ciltacabtagene autoleucel) the dominant drugs in oncology. However, in vivo CAR-T is starting to dominate R&D activities because it eliminates the need for expensive and convoluted manufacturing. Big pharma companies are starting to favour this approach for pipeline strategies, too. J&J, for example, inked a collaboration and potential buyout agreement with in vivo CAR-T specialist Sail Biomedicines worth up to $3.505bn in July 2026. Eli Lilly, AstraZeneca, and Moderna have all also set targets on the in vivo CAR-T space.

For Caribou, the business wind-down marks a strong contrast to when it burst onto the biotech scene with so much promise. It was co-founded by Jennifer Doudna, who won the 2020 Nobel Prize in Chemistry alongside Emmanuelle Charpentier for their development of CRISPR-Cas9 genome editing.  The biotech went on to have a successful $350m IPO in the US and even received financial backing from Pfizer and AbbVie.

Haurwitz remained steadfast in the positive evidence supporting the company’s clinical programmes, saying: “These are not merely scientific concepts. These product candidates are therapies that have already made a difference in patients’ lives and could help many more.

“As our board considers potential paths forward for the company and its assets, we hope there may be an opportunity for these off-the-shelf CAR-T cell therapies to be advanced by other organisations with the resources, capabilities, and commitment required.”