Caribou Biosciences entered the scene in 2011 and went public in 2021. Over the course of its existence, the biotech has received funding and support from a handful of Big Pharma players, including Novartis, AbbVie and Pfizer.
Caribou Biosciences, co-founded by Nobel Prize-winning CRISPR pioneer Jennifer Doudna, is discontinuing its entire clinical-stage pipeline and executing “substantial” workforce cuts amid a financing freeze in the CAR T space.
“Caribou’s story has taken a heartbreaking turn,” CEO Rachel Haurwitz wrote in a LinkedIn post on Tuesday.
As part of a strategic review, Caribou could consider a merger, acquisition, business combination, or other strategic transactions involving the company and/or its assets. The decision, disclosed in a Tuesday news release, “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,” Haurwitz wrote.
Shares of the biotech crashed 43% to 64 cents apiece in early-market trading on Wednesday morning.
The biotech will halt all ongoing clinical trials and any further development of its allogeneic CAR-T candidates as part of the restructuring initiative. The company has two active assets: the CD19-targeting vispa-cel for B cell non-Hodgkin lymphoma, and the anti-BCMA CB-011 for multiple myeloma.
“This is an extraordinarily difficult decision, particularly because it is in no way a reflection of our belief that vispa-cel and CB-011 have the potential to benefit patients,” Haurwitz said.
Vispa-cel, which in March was awarded the FDA’s regenerative medicine advanced therapy designation, elicited an 82% overall response rate in patients with second-line large B cell lymphoma in the Phase 1 ANTLER trial, according to a June readout. Complete response rate was 67% while median progression-free survival was 17.1 months. Aside from tumor response, ANTLER also looked at safety as a primary endpoint, with Caribou documenting no cases of graft-versus-host disease (GvHD) or severe immune effector cell-associated neurotoxicity syndrome (ICANS). There was one instance of severe cytokine release syndrome.
That same month, Phase 1 data from the CaMMouflage study showed a 92% overall response rate—a primary endpoint alongside dose-limiting toxicities—in patients treated with CB-011. There were no cases of GvHD, immune effector cell-associated enterocolitis—a rare complication of CAR T therapy characterized by diarrhea—parkinsonism or severe ICANS.
As of June 30, Caribou still had $113.8 million in cash, cash equivalents and marketable securities, enough to fund dose-expansion assessments for CB-001 and start-up activities for the pivotal Phase 3 ANTLER-3 study for vispa-cel, the biotech said in its second quarter report in August. At the time, Caribou estimated its runway to last through the end of 2027.
As part of Caribou’s efforts to seek out strategic alternatives, the company will enact a “substantial reduction” of its headcount, though the number of people affected was not revealed. Caribou had 97 full-time employees as of Feb. 27, 2026, according to an annual SEC report. The company expects to absorb around $15 million to $19 million in restructuring costs.
Caribou was founded in 2011 by CRISPR trailblazer Doudna, alongside UC Berkeley alumni Haurwitz and Martin Jinek and UC Berkeley professor James Berger.
From the beginning, the company sought to develop off-the-shelf CAR T therapies for hematologic cancers and autoimmune diseases—a mission that in May 2016 helped the biotech close a Novartis-backed series B round, bringing in $30 million in proceeds.
In March 2021, Caribou secured $115 million in a series C effort that involved participation from AbbVie. The pharma weeks prior paid $40 million to collaborate with the biotech to advance two CRISPR-edited cell therapies for solid tumors. AbbVie ended the agreement in September 2023.
In July 2021, Caribou went public with a $304 million raise.
Aside from AbbVie and Novartis, Pfizer has also given its vote of confidence to Caribou’s tech with a $25 million equity investment in July 2023.
Caribou is not the only company developing allogeneic CAR T therapies that has run into challenges. AvenCell Therapeutics CEO Andrew Schiermeier called the environment a “nuclear winter” in a February interview with Fierce Biotech. Money has instead flowed to autologous and in vivo CAR T therapies.
