Epsilogen acquires TigaTx to boost pan-isotope cancer antibody pipeline

UK – UK biotech Epsilogen has announced its acquisition of US-based TigaTx, a strategic move aimed at consolidating expertise in developing pan-isotope cancer antibodies.

This acquisition strengthens Epsilogen’s pioneering work in antibody therapeutics, building on its reputation as the first biotech to commence clinical testing of a cancer antibody based on immunoglobulin E (IgE).

While most therapeutic antibodies belong to the IgG class, Epsilogen has been a maverick in exploring IgE-based therapies.

Now, with TigaTx’s specialized focus on IgA antibodies, the combined entity is set to offer an unprecedented range of options by selecting the most appropriate antibody isotype based on the specific cancer.

The newly acquired TigaTx brings capabilities centered on IgA antibodies, which are renowned for their efficiency in activating neutrophils—a key component of the immune response—while IgE antibodies, in contrast, have been shown to mediate effects via 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,” explained Epsilogen chief executive Tim Wilson.

Wilson added that the merger opens up prospects for developing hybrid antibodies that merge different isotype functions into a single molecule.

These hybrid antibodies could potentially activate multiple compartments of the immune system simultaneously, while also offering improved pharmacological profiles.

With TigaTx now operating as a subsidiary of Epsilogen, the combined portfolio is set to span a diverse range of antibody modalities.

This includes products that fuse IgE and IgG functionality into a single molecule known as IgEGs, bispecific antibodies that can bind two different antigens simultaneously, and IgA molecules with optimized manufacturing profiles.

Financial details of the deal have not been disclosed; however, it follows last year’s successful financing rounds that raised US $35.5 million and £43.25 million (US $55 million).

The merger also enhances the pipeline of next-generation cancer therapies. One of the key clinical-stage candidates is Epsilogen’s folate receptor alpha-targeting MOv18 Ig, which is currently undergoing a phase 1b proof-of-concept study in patients with platinum-resistant ovarian cancer.

This candidate is poised as a potential rival to AbbVie’s Elahere (mirvetuximab soravtansine), approved by the FDA in 2022.

Meanwhile, TigaTx is contributing its candidate, TIGA-001, now renamed EPS 401. This anti-EGFR IgA antibody is undergoing preclinical studies with plans to enter human trials in 2026, and it shows promise for patients who are resistant or intolerant to current anti-EGFR therapies.