Caribou Biosciences is the latest biotech to rake in an upsized IPO. The cell therapy player bagged $304 million in a Wall Street debut, which will see its lead CAR-T program through a first phase 1 readout and propel two prospects toward—and maybe also into—the clinic.
In a move that’s becoming the norm in biotech, Caribou filed to raise up to $100 million in its IPO in early July. On Monday, the company revealed a new goal of $203 million in a securities filing, bumping that up further to $255 million on Thursday by adding 26% more shares to the deal. Caribou eventually banked $304 million by offering 19 million shares—41% more than originally planned—at $16 apiece, according to a statement.
About $90 million of the proceeds will bankroll CB-010, an anti-CD19 CAR-T, through the clinic, Caribou said in a securities filing. That includes the initial readout of a phase 1 study that started last week in patients with B cell non-Hodgkin lymphoma whose cancer returned after treatment or didn’t respond in the first place. The company expects to report those data in 2022.
Another $80 million will support the development of two preclinical CAR-T assets: CB-011, a BCMA-targeting CAR-T in development for the treatment of multiple myeloma and CB-012, a CAR-T targeting CD371 for the treatment of acute myeloid leukemia. The funds will bankroll IND-enabling studies for both programs and, potentially, the start of their clinical trials, according to the filing. Caribou hopes to start human trials for CB-011 and CB-012 in 2022 and 2023, respectively.
All three programs are allogeneic CAR-T therapies, meaning they are made from donor cells rather than a patient’s own cells like the four approved CAR-T therapies from Novartis, Gilead’s Kite unit and Bristol Myers Squibb.
Those types of treatments, known as autologous, can be complicated and time-consuming to make. Cells must be harvested from the patient, modified to fight cancer and then put back into the patient. Some patients are too sick to wait for these treatments to be made, while others don’t have enough T cells, or T cells of good enough quality, to turn into treatments.
Caribou’s lead programs are all CAR-Ts that target blood cancer, but it is also working on allogeneic natural killer (NK) cell therapies based on pluripotent stem cells for solid tumors. About $55 million will support this work, as well as discovery-stage research and the development of the CRISPR technology it uses to make cell therapies, Caribou said in the filing.
Caribou is one of several players working to overcome the limits of the first generation of cell therapies. In 2018, a pair of former executives from Kite Pharma—the company behind Yescarta, the second FDA-approved CAR-T—launched Allogene, a biotech that started out with $300 million and 17 off-the-shelf CAR-T assets licensed from Pfizer.
Gilead, which snapped up Kite for $12 billion in 2017, made a move toward off-the-shelf treatments in June. The company teamed up with Shoreline Biosciences in a deal that could exceed $2.3 billion to develop allogeneic NK cell treatments for blood cancers. Other companies, such as Catamaran Bio, are also working on NK cell therapies, but as a way to tackle solid tumors.