Chasing AnaptysBio and Lilly, MiroBio rounds up $97M for autoimmune checkpoint agonist clinical trials

Medicxi, OrbiMed and other VCs have joined forces to help MiroBio flip immune checkpoint R&D on its head, committing $97 million to support development of BTLA and PD-1 autoimmune programs that put the British biotech on turf targeted by AnaptysBio and Eli Lilly. 

MiroBio made news back in 2019, when it raised a 27 million pounds sterling ($33 million) series A to build on Simon Davis and Richard Cornall’s research at the University of Oxford. The biotech used the money to create a discovery platform that features a checkpoint atlas, in support of its ambition to study the entire class of receptors, and antibody engineering capabilities. In parallel, MiroBio advanced lead programs against BTLA and PD-1. Armed with the series B funds, MiroBio will take off from the platform it has established.

“With this financing, we'll be able to advance both those lead programs and get clinical data on them, as well as move forward some of the earlier stage programs that we're really excited about and some receptors that we're not aware of others having studied as of yet for this particular application,” Eliot Charles, Ph.D., chairman of MiroBio, told Fierce Biotech.

The BTLA prospect, MB272, is the most advanced, with MiroBio set to enter the clinic imminently having recently secured the green light from the U.K. regulator. Expressed on B and T cells, BTLA offers a chance to down-modulate the activity of immune cells to treat a range of inflammatory diseases. That potential has attracted a small band of drug developers. 

Having delivered top-line early-phase data in April, AnaptysBio is preparing to start a midphase study of its anti-BTLA agonist in the second half of 2022. Eli Lilly is testing a BTLA agonist in patients with systemic lupus erythematosus in a phase 2 clinical trial. As Charles sees things, rival programs have shown there is “true clinical potential” for BTLA agonists while leaving room for MiroBio to differentiate its candidate.

“We think ours is a little bit different. And with these differentiated effects that we've seen preclinically, we think this will translate into a meaningful clinical benefit,” Charles said. “The differentiation is coming from both sides of the platform. Clearly our antibody has been designed differently than others that we're aware of out there and this leads to functional effects. On the other side, it's using this checkpoint atlas to really understand where we can best utilize BTLA agonists.”

MiroBio will also need to come from behind in PD-1. AnaptysBio took an anti-PD-1 agonist into phase 2 late last year. Johnson & Johnson has a PD-1 candidate in phase 1, while Merck entered the space through its acquisition of Pandion Therapeutics, which gave it control of a preclinical PD-1 agonist.

As MiroBio prepares to show how its candidates stand out from the pack, it's expanding its team. Sanjay Keswani, formerly of companies including Roche, recently came on board as chief medical officer, joining Chief Scientific Officer Lynne Murray, Ph.D., in the C-suite. MiroBio is building out Keswani’s clinical team while “looking for new leadership for the company,” Charles said.