Cytovia inks SPAC merger to get natural killer cells prospects into the clinic

Cytovia Therapeutics has found an "ISLE" to dock at in the choppy waters of biotech public markets. The natural killer (NK) cell startup is set to merge with a special purpose acquisition company (SPAC) to secure the cash to enter the clinic and try to get through to a data drop in 2024.

Isleworth Healthcare Acquisition Corp. has taken the other side of the deal. With $207 million in trust, the SPAC has been on the hunt for an emerging healthcare company to take public.

Isleworth has also secured an additional $20 million for the deal from new investors, who are coming together to support development of gene edited NK cells derived from induced pluripotent stem cells (iPSCs) and antibodies that engage NK cells. All of Cytovia's candidates are preclinical, with FDA applications planned for this year and next.

CYT-303, a tri-specific antibody designed to bind to liver cancer cells via the glycoprotein GPC3, is leading the way. Cytovia plans to file with the FDA for approval of the NK-cell engager as a monotherapy and in combination with unedited NK cells this year. CYT-338, a CD38 NK-cell engager, is the other candidate on the 2022 slate of FDA submissions. Cytovia is developing the candidate for use in multiple myeloma.

Other companies already have NK-cell engagers in the clinic but Cytovia’s targeting of GPC3 and CD38 on cancer cells and NKp46 and CD16 on NK cells sets it apart. Innate Pharma’s Sanofi-partnered IPH6101 hits both the NK targets but it is more common for drug candidates to engage the cells via CD16 alone. Cytovia sees the sustained expression of NKp46 as an advantage of its approach. 

The biotech’s first gene edited NK cell therapies are expected to be ready for FDA submission in 2023. Cytovia’s pipeline features the gene edited CYT-150 and CAR-NK prospects directed at GPC3, CD38 and EGFR, all of which are slated for FDA applications next year. Companies including Takeda, Legend Biotech and Regeneron, through its alliance with Adicet, are aiming CAR-T therapies at the solid tumor target GPC3.

Cytovia’s use of iPSCs to generate CAR-NKs could give it an advantage over CAR-T players and companies developing donor-derived natural killer cells, if the technology lives up to its potential. In theory, using iPSCs can eliminate batch-to-batch variation and realize benefits all NK cells may have over T cells, such as a clearer path to allogeneic use and lower risk of cytokine release syndrome. 

One question now is how investors will react to the deal. More and more SPAC deals are coming unstuck because investors in the acquisition vehicles are withdrawing cash after learning of the takeover target and because of shortfalls in the amounts raised from private investors to add to the merger haul.