US-based biopharmaceutical firm Gilead Sciences has signed a definitive agreement to acquire all of the outstanding shares of MiroBio for a cash consideration of around $405m.

MiroBio is a UK-based biotechnology company focused on restoring immune balance with agonists targeting immune inhibitory receptors.

Through the acquisition, Gilead will obtain MiroBio’s unique drug discovery platform, along with its complete range of immune inhibitory receptor agonists.

The transaction is expected to be completed, subject to expiration or termination of the waiting period under the Hart-Scott-Rodino Act, and other customary conditions.

Gilead Sciences research executive vice president Flavius Martin said: “The team at MiroBio has spearheaded foundational research for agonist antibodies following a rigorous scientific approach.

“We believe that MiroBio’s unique platform technology has the potential to produce best-in-class agonist antibodies targeting immune inhibitory receptors.”

Gilead will obtain MB272, MiroBio’s lead investigational antibody candidate, currently being developed in Phase 1 clinical trials.

MB272 is a selective agonist of immune inhibitory receptor B- and T-Lymphocyte Attenuator (BTLA), that targets T, B and dendritic cells to inhibit inflammatory immune response.

MiroBio’s I-ReSToRE (REceptor Selection and Targeting to Reinstate immune Equilibrium) platform enables advanced agonist antibodies to target immune inhibitory receptors.

The company developed the platform by combining its advanced receptor mapping database and visualization tool, Checkpoint Atlas, with its unique antibody engineering.

Gilead intends to advance additional agonists derived from I-ReSToRE platform, including a PD-1 agonist MB151, and other early-stage programs.

MiroBio chairman Eliot Charles said: “We are excited to be joining Gilead. MiroBio has a deep understanding of checkpoint receptor signalling and a proprietary approach to selecting and generating superior agonist antibodies.

“Combining this with Gilead’s drug development and therapeutic area expertise will allow us to fully explore the potential of checkpoint agonist antibodies for patients with autoimmune disease.”

Spun out of Oxford University in 2019, MiroBio is backed by Oxford Science Enterprises, Samsara BioCapital, SR One, Medicxi, Advent Life Sciences, OrbiMed and Monograph.