This First-in-Human (FIH) Phase 1/2 study will evaluate the safety, pharmacological activity, and efficacy of mRNA-3927 in participants 1 year of age and older with genetically confirmed propionic acidemia (PA). This study is designed to characterize the safety, tolerability, and pharmacological activity (as assessed by biomarker measurements) and to determine the optimal dose of mRNA-3927 in participants with PA. After establishing a dose with acceptable safety and pharmacodynamic (PD) response in a Dose Optimization Part (Part 1), additional participants will be enrolled into the study in a Dose Expansion Part (Part 2) to allow for further characterization of the efficacy, safety, and PD of mRNA-3927.
A Global, Phase 1/2, Open-Label, Dose Optimization Study to Evaluate the Safety, Pharmacodynamics, and Pharmacokinetics of mRNA-3927 in Participants With Propionic Acidemia
During the Dose Optimization Stage, after each dose cohort is fully enrolled, and the dose-limiting toxicity (DLT) observation window of at least 14 days is complete for the final participant in that cohort, the Sponsor will review the totality of available safety data in conjunction with all available PK/PD data. Based on this review, the Sponsor will recommend a revised dose and/or dosing interval. The Sponsor will abide by predefined constraints as to the maximum percentage change in dose and dose interval. A maximum of 9 cohorts will be enrolled in Part 1 (Dose Optimization).
Upon establishment of a dose with acceptable safety and pharmacodynamic activity in a Dose Optimization Part (Part 1), additional participants will be enrolled into the study in a Dose Expansion Part (Part 2) to allow for further characterization of the safety, efficacy, and pharmacodynamics of mRNA-3927.
Participants in both phases of study will participate in a predosing observational period, followed by a treatment period, and then a follow-up period after withdrawal of treatment.
