MB-151

Gilead Sciences has announced its plans to acquire UK-based biotechnology company MiroBio. The privately-held company focuses its research efforts on restoring immune balance with agonists targeting immune inhibitory receptors. The deal is worth approximately $405m in cash, subject to customary adjustments. The acquisition will allow Gilead to utilise MiroBio’s proprietary discovery platform and entire portfolio of immune inhibitory receptor agonists. In 2019, MiroBio became a spin-out of Oxford University and is based on more than 15 years of foundational research from the labs of Professor Simon Davis and Professor Richard Cornall. The company’s lead investigational antibody, MB272, is a selective agonist of immune inhibitory receptor B- and T-Lymphocyte Attenuator (BTLA), which has entered phase 1 clinical trials. MB272 targets T, B and dendritic cells to inhibit or blunt activation and suppress an inflammatory immune response. MiroBio’s REceptor Selection and Targeting to Reinstate immune Equilibrium – I-ReSToRE platform – has the potential to be used as a novel approach for the treatment of inflammatory diseases, by creating best-in-class agonist antibodies targeting immune inhibitory receptors. The company developed I-ReSToRE and combined it with its Checkpoint Atlas – a receptor mapping database and visualization tool – with proprietary antibody engineering. The I-ReSToRE platform works to identify and develop therapeutics that engage inhibitory signalling networks with the aim of restoring immune homeostasis for patients. Gilead expects to advance additional agonists derived from MiroBio’s I-ReSToRE platform, including a PD-1 agonist, MB151, and other undisclosed early-stage programmes, over the next several years. Commenting on the acquisition, Flavius Martin, executive vice president, research, Gilead Sciences, 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.” According to the conditions of the agreement, Gilead will acquire all of the outstanding share capital of MiroBio for a total of $405m in cash, subject to customary adjustments, which is payable upon completion. Eliot Charles, chairman of MiroBio, said: “MiroBio has a deep understanding of checkpoint receptor signalling and a proprietary approach to select and generate 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.”

Josh Edelson/AFP via Getty Checkpoint inhibitors, such as Merck’s Keytruda, have demonstrated a powerful effect on the body’s immune system in the fight against tumors. Gilead Sciences is banking on a differentiated approach with checkpoint agonists in its ongoing crusade against autoimmune diseases. On Thursday, the California-headquartered company snapped up U.K.-based MiroBio in a $405 million deal that will bring its checkpoint agonists and discovery platform under Gilead's umbrella. Checkpoint pathways play a significant role in regulating immune cell function. Through the checkpoint agonists, MiroBio aims to harness the natural control mechanisms within the immune system and “restore the balance” within the body, keeping these diseases in check. MiroBio and Gilead believe they can offer new, best-in-class assets to patients beset by different autoimmune diseases. The deal includes MiroBio’s lead investigational candidate, MB272, a selective agonist of T, B and dendritic cells that aims to inhibit or blunt activation and suppress an inflammatory immune response. Earlier this week, MiroBio, which was founded three years ago, dosed the first patient in a Phase I study with the B- and T-lymphocyte Attenuator (BTLA) targeting asset. Multiple Suitors Taking Notice of MiroBio Eliot Charles, Ph.D., chairman of MiroBio, told BioSpace he was pleased with the progress the company has made since it spun out of the University of Oxford in 2019. It’s that progress that has attracted the likes of Gilead, a leader in treating autoimmune diseases. Charles shared that about a year ago, MiroBio began to talk with other companies after seeing positive data from its developmental agonist programs. That data received a significant amount of recognition from these companies, he said. During the course of those talks, Gilead took notice of the company and Charles said it didn’t take too long before the two realized how well they could serve the patient communities by combining forces. “We’ve been able to demonstrate what the leading assets in our platform can do and that has drawn the attention of other companies,” Charles said. “MiroBio has a deep understanding of checkpoint receptor signaling and a proprietary approach to select and generate 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.” Flavius Martin, EVP of research at Gilead, touted the research conducted at MiroBio. In a brief statement, Martin said the company researchers have “spearheaded foundational research for agonist antibodies following a rigorous scientific approach.” Martin added that Gilead believes MiroBio’s platform technology will be able to produce best-in-class agonist antibodies targeting immune inhibitory receptors. The Broad Potential of BTLA Agonists MiroBio isn’t the only company focused on BTLA. Eli Lilly is assessing a BTLA-focused candidate in a Phase II study in lupus erythematosus. Earlier this year, San Diego-based AnaptysBio announced positive top-line data from a Phase I study of its anti-BTLA agonist antibody, ANB032. MiroBio’s MB272, which has potential applications in multiple autoimmune diseases, was developed with the company’s I-ReSToRE (REceptor Selection and Targeting to Reinstate immune Equilibrium) platform. The platform, Charles said, is used to develop potential best-in-class agonist antibodies targeting immune inhibitory receptors, of which there are approximately 70. He noted that what immuno-oncology-focused companies have been able to accomplish with the inhibition of checkpoints shows how important they are to human health. By using the company’s proprietary agonists to unlock the potential of the checkpoints in order to dampen an overactive immune response, Charles speculated that the assets will be able to generate leading responses in multiple disease indications. “There are more than 70 receptors that have differential expression patterns,” he said, adding that this leads to numerous opportunities for the company. He said the I-ReSToRE platform supports the identification and development of therapeutics that use inhibitory signaling networks to understand the role of the receptors in various disease states. However, what autoimmune diseases Gilead has in mind for the MiroBio platform remains to be seen. In addition to supporting the continued development of MB272, the company intends to advance MB151, a PD-1 agonist, as well as other early-stage programs over the next few years. Over the coming weeks, Charles said MiroBio will sit down with Gilead to talk about the different assets and “share ideas” on which disease indications they could be aimed at. However, he said with the acquisition having just been announced, he is not sure of a potential timeline for that discussion. The small company is well-funded. In June, MiroBio secured $97 million in a Series B financing round to support the development of MB272 and MB151 and its I-ReSToRE platform. That series B was backed by a strong group of trans-Atlantic investors, including Oxford Science Enterprises, Samsara BioCapital, SR One, Medicxi, Advent Life Sciences, OrbiMed and Monograph. The company launched with a $34 million Series A. In conclusion, Charles said, “I’m really excited that MiroBio will become part of Gilead Sciences I will be keenly focused on getting the integration right.”