Epsilogen buys rival cancer antibody firm TigaTx
Epsilogen chief executive Tim Wilson
UK biotech Epsilogen has bought US-based TigaTx, pooling their resources to create what it says will be a leader in 'pan-isotope' cancer antibodies.
Epsilogen rose to prominence a few years ago by becoming the first biotech to start clinical testing of an antibody therapy for cancer based on immunoglobulin E (IgE), a departure from most therapeutic antibodies that belong to the IgG class. It's stayed with the maverick approach with its purchase of TigaTx, as the US company focuses on IgA-based antibodies.
Joining forces means that the combined company can now select "the most appropriate antibody isotype for a given cancer," according to a joint statement, which notes that IgA antibodies are good at activating neutrophils, while IgE antibodies tend to exert their effects through T cells and macrophages.
"Combining the capabilities of Epsilogen with those of TigaTx gives us the ability to choose the most relevant isotype for a given cancer, whether a cold tumour environment we want to drive multiple immune effector cells into or leverage neutrophils," said Epsilogen chief executive Tim Wilson.
He also said that the merger opens up the prospect of combining different isotype functions into a single antibody molecule. These hybrid antibodies have the potential to activate multiple compartments of the immune system, as well as offer improved pharmacological profiles.
Now, Epsilogen's portfolio can span antibodies which combine IgE and IgG functionality into a single molecule (IgEGs), bispecific IgEs and IgEGs that can bind two different antigens simultaneously, and IgA molecules with improved manufacturing profiles.
Both biotechs are privately held, and financial terms have not been disclosed. Boston-based TigaTx will now operate as a subsidiary of Epsilogen, and the transaction follows financings of $35.5 million and £43.25 million (around $55 million), respectively, last year.
The combined pipeline includes one clinical-stage candidate, namely Epsilogen's folate receptor alpha-targeting MOv18 Ig, a phase 1b proof-of-concept study in platinum-resistant ovarian cancer, and a potential rival to AbbVie's Elahere (mirvetuximab soravtansine), which was approved by the FDA in 2022.
Meanwhile, TigaTx, which has been flying under the radar until now, is contributing TIGA-001 (now renamed EPS 401), an anti-EGFR IgA antibody with studies underway to prepare for human trials in 2026.
The company has said its IgA-based drug has the potential to benefit patients with resistance or intolerance to approved anti-EGFR therapies, noting that less than 25% of patients respond to the current generation of drugs.
