Dive Insight:

Pfizer’s backing provides a boost both for investor sentiment and development expertise. As part of the sale, Caribou said Thursday that its board will also now include Sriram Krishnaswami, who runs development of multiple myeloma products at Pfizer.

Caribou went public in 2021 with one of the most lucrative initial stock offerings among gene-editing companies. The promise of the company’s allogeneic or “off-the-shelf” cell therapies, engineered with the help of CRISPR gene editing technology, brought in $304 million just four months after a private round of investment worth $115 million.

But as with other developers of allogeneic treatments, questions have since emerged about the durability of Caribou’s drugs. Data released in June 2022 for its lead therapy for non-Hodgkin lymphoma showed that of six patients who’d received treatment, three relapsed within a year, including one whose cancer returned after three months. One patient remained cancer-free when Caribou reported the results.

Pfizer, meanwhile, has pared back some of its own work in gene therapy while continuing to seek opportunities outside the company. In 2022, Pfizer signed a four-year research partnership with Beam Therapeutics focused on three base editing targets in the liver, muscle and central nervous system. Back in 2020, Pfizer made a $60 million investment in the gene therapy company Homology Medicines.

Pfizer has also invested in allogeneic cell therapy before. Deals with Servier and Cellectis yielded a portfolio of allogeneic therapies that were spun into Allogene Therapeutics, now a high-profile developer of the off-the-shelf treatments. Pfizer held a 25% stake in Allogene when it was launched in 2018, and remained its largest shareholder as of April, according to a regulatory filing.