Mereo Biopharma Group (MREO) investor relations material

Program updates and regulatory interactions

• Two late-stage programs: setrusumab for osteogenesis imperfecta (OI) in regulatory discussions after recent phase III data, and alvelestat for alpha-1 antitrypsin deficiency (AATD), phase III-ready and seeking a partner.

• Regulatory discussions for setrusumab involve multiple agencies (FDA, EMA, MHRA) and are expected to take several months, with updates anticipated before year-end.

• Analyses of ORBIT and COSMIC studies show setrusumab reduced fractures in pediatric OI patients, improved bone mineral density (BMD), and led to significant pain reduction and increased activity, though primary endpoints were not met.

• Open label extension studies are ongoing, monitoring fractures, BMD, pain, and activity, with most patients transitioning to this phase.

• Reimbursement and HTA discussions in Europe are ongoing in parallel with regulatory processes, focusing on comparator data and launch sequence.

Clinical and market insights

• Clinicians emphasize the importance of vertebral fracture reduction and pain relief in OI, as these are key drivers for treatment initiation.

• Alvelestat targets both early and late-stage AATD patients, aiming for prevention and reduction of exacerbations, with a phase III trial planned to start around year-end, pending partnership.

• The AATD market is evolving with new oral therapies and gene editing platforms; alvelestat's differentiation lies in its oral dosing and inclusion of early-stage patients.

• Vantictumab, partnered with āshibio, is being prepared for phase II in osteopetrosis, with European rights retained and clinical work ongoing.

• Cash position at end of Q1 was $36 million, providing runway into mid-2027, excluding potential business development income.