Mereo Biopharma Group (MREO) Corporate presentation summary

Portfolio and strategy

• Three rare-disease programs target osteogenesis imperfecta (OI), AATD-associated lung disease (AATD-LD) and osteopetrosis; strategy emphasizes in-licensing, focused rare-disease expertise and partnerships.

• Setrusumab is partnered with Ultragenyx; alvelestat has a Sentynl option and licence agreement; vantictumab is licensed to āshibio, with European rights retained.

• Setrusumab and alvelestat each target stated market opportunities exceeding $1bn; OI and AATD-LD have high unmet need.

Setrusumab for OI

• Orbit and Cosmic Phase 3 studies did not meet their primary endpoint of reducing annualized fracture rate (AFR); both showed statistically significant increases in bone mineral density.

• Additional analyses reported fewer vertebral fractures and improvements in patient-reported disease severity, pain/comfort and daily activities.

• Post-hoc analyses in patients under 18 with more than three baseline fractures over two years found numerically lower AFR in Orbit versus placebo (p=0.063) and significantly lower AFR in Cosmic versus IV bisphosphonates (p=0.009).

• No new safety concerns were identified; reported treatment-emergent adverse events were consistent with the anticipated safety profile.

• FDA discussions are underway to determine prospective clinical data needed to support a BLA; Ultragenyx leads and funds global development, while potential terms include up to $245M in further milestones and shared PRV proceeds.

Alvelestat for AATD-LD

• A Phase 3 trial design is being refined for an estimated 220–250 patients over up to 18 months, with SGRQ and CT lung density as independent primary endpoints; FDA interactions are ongoing.

• Phase 2 data included efficacy evidence across biomarkers, patient-reported outcomes and exacerbations; the combined exacerbation analysis had p=0.326.

• Sentynl option exercise would trigger a $40M exercise fee and R&D funding, up to $435M in regulatory and commercial milestones, and tiered double-digit US royalties.

• Phase 3 initiation could follow in early 2027, assuming option exercise after FDA interactions.