Rallybio (RLYB) TD Cowen 45th Annual Healthcare Conference summary

Pipeline and program updates

• Three major programs advancing: FNAIT (phase II), complement Factor V inhibitor (phase I moving to II), and oral ENPP1 inhibitor for hypophosphatasia (preclinical).

• FNAIT program targets prevention of a rare immune-mediated fetal platelet destruction, with first pregnant patient dosed and data readouts expected in 2Q and 3Q this year.

• Complement Factor V inhibitor shows best-in-class potential, with improved manufacturing and dosing, aiming for weekly subcutaneous administration and targeting PNH, gMG, and antiphospholipid syndrome.

• ENPP1 inhibitor, developed with Recursion, aims to provide a once-daily oral therapy for hypophosphatasia, addressing significant unmet need in milder forms not covered by current enzyme replacement.

• Financial position strong with over $65 million in cash, supporting operations into the second half of next year.

Market opportunities and strategy

• FNAIT program estimated at $1.6 billion market opportunity, with focus on prevention and collaboration with Johnson & Johnson for treatment of sensitized mothers.

• Complement Factor V inhibitor positioned for market share in established indications and new preventative uses, leveraging patient preference for convenient, stable, at-home administration.

• ENPP1 inhibitor targets a broader patient population than current therapies, with potential to reduce burden and cost of care.

• Ongoing engagement with payers, prescribers, and guideline committees in the US and Europe to support future adoption and reimbursement.

Clinical and technical milestones

• FNAIT phase II trial de-risking regulatory, patient recruitment, and technical aspects; first mother enrolled, with focus on pharmacokinetics during pregnancy.

• Complement Factor V inhibitor phase I aims to demonstrate high-dose tolerability, complete C5 knockdown, and prevention of hemolysis using updated assays.

• ENPP1 inhibitor development focuses on improving drug-like properties such as bioavailability and stability for chronic use.

• Key milestones for 2024 include FNAIT PK data, additional patient recruitment, dose optimization for complement inhibitor, and preclinical progress for ENPP1 inhibitor.