PepGen Inc. Q4 FY2022 earnings call

• PepGen presented exon skipping data from Phase 1 trial of EDO51 in healthy volunteers, showing high levels of oligonucleotide delivery and exon-51 skipping. Non-clinical data in non-human primates and mdx mice supported potential of EDO51 for DMD. - EDODM1 non-clinical data showed reduction of pathogenic nuclear foci and liberation of MBLN1 in DM1 patient cells. - In 2022, PepGen went public, appointed board members and senior management. - Plans for 2023 include initiating CONNECT1-EDO51 (open label Phase 2 MAD in Canada), CONNECT2-EDO51 (Phase 2 global double-blind placebo-controlled), and FREEDOM-DM1 (single ascending dose in DM1 patients). Data expected in 2024 from these trials.

No specific product segments with revenue contribution % were detailed in the transcript. Financials noted: As of Dec 31, 2022, cash and cash equivalents were $181.8 million vs $132.9 million in 2021. Net loss for Q4 2022 was $14.9 million vs $7.1 million in 2021. Full year 2022 net loss was $69.1 million vs $27.3 million in 2021. R&D expenses Q4 2022 were $13.2 million vs $4.5 million in 2021. Full year 2022 R&D expenses were $54.1 million vs $19.0 million in 2021. G&A expenses Q4 2022 were $4.0 million vs $2.7 million in 2021. Full year 2022 G&A expenses were $14.2 million vs $8.1 million in 2021.

• Expect to initiate CONNECT1-EDO51 in Canada first half of 2023, report dystrophin data in 2024. - Plan to initiate CONNECT2-EDO51 in second half of 2023, potentially supporting accelerated approval. - Expect to initiate FREEDOM-DM1 in first half of 2023, report safety and other data in 2024.

Q: Regarding the global DMD study set to initiate in second half of 2023, have you talked to the FDA yet and how the open label study informs the pivotal?

A: Have had conversations with regulators, clinical design informed by that. Balancing to deliver dystrophin data in 2024, open label study in Canada data will be integrated into global study. Global study needs to be 6-month dosing study, toxicology studies to be completed by end of 2023.

Q: Color on dose cohorts for CONNECT1 and 2 studies and potential to dose above 15 mg/kg?

A: Think 10 mg/kg is safe and well tolerated, delivered significant exon-skipping in single dose study. Single dose at 10 mg/kg showed sevenfold higher exon-skipping than previously reported. Non-human primate study with 20 mg/kg single dose showed 2.5% exon-skipping, four monthly doses showed 35% exon-skipping. May have conversations with regulators about dosing above, patient safety front and center.

Q: On regulatory landscape, advisory committee meeting for DMD candidate, thoughts on dystrophin as surrogate endpoint and timing for dystrophin production assessment in CONNECT2?

A: Upcoming advisory committee meeting focused on microdystrophin. Exon-skipping agent produces slightly truncated dystrophin, functional in Becker patients. In CONNECT2, will look at muscle biopsies at baseline and week 25 for dystrophin production after ~24 weeks of treatment.

Q: Differences in physical properties of EDO51's cell penetrating peptide vs others and drivers of increased exon-skipping?

A: Molecule is shorter than 20 amino acid linear peptide, synthetic, with three motifs, arginines interspersed by non-natural amino acids for stability, short hydrophobic core. Believed to confer better access to cells and nucleus for oligonucleotide, leading to increased exon-skipping.