Propionic Acidemia

Propionic acidemia is a genetic metabolic disorder characterized by metabolic acidosis, ketosis, vomiting, lethargy, cognitive impairment, and risk of death. It results from loss of function of the mitochondrial enzyme propionyl-CoA carboxylase and can be due to disease-causing variants in the PCCA gene, leading to accumulation of propionyl-CoA and its toxic metabolites. The purpose of this trial is to evaluate the safety and potential therapeutic benefit of an AAV-based gene therapy for propionic acidemia in patients with genetically confirmed biallelic variants in PCCA.

Background: People s bodies need to break down food into the chemicals. These chemicals are used for energy and growth. Some people cannot process all chemicals very well. Too much of some chemicals can cause diseases. One of these diseases is called propionic acidemia (PA). People with PA can have problems with growth, learning heart, abdomen, and other organs. Researchers want to better understand how these problems happen. Objective: To learn more about propionic acidemia and the genes that might contribute to it. Eligibility: People at least 2 years old with PA who can travel to the clinic Some unaffected family members Design: Participants will have a 3 to 5-day hospital visit every year or every few years. Family members may have just 1 visit. During the family member visit, they may have: Medical history Physical exam Samples of blood and urine Questions about diet and a food diary Doctors and nurses may do additional studies: Samples of saliva, skin and stool Fluid from a gastronomy tube, if participants have one Dental and eye evaluations A kidney test - a small amount of dye will be injected and blood will be collected. Consultations with specialists A test of calories needed at rest. A clear plastic tent is placed over the participant to measure breathing. Stable isotope study. Participants will take a nonradioactive substance then blow into a bag. Photos taken of the face and body with underwear on Ultrasound of the abdomen Heart tests Hand x-ray Brain scan Participants may have other tests if study doctors recommend them. They will get the results of standard medical tests and genetic tests.

The main purpose of this study is to evaluate the long-term safety of mRNA-3927 administered to participants with propionic acidemia (PA) who have previously participated in Study mRNA-3927-P101 (NCT04159103).

This is a non-interventional, observational, global, multicenter, study describing participant characteristics, clinical outcomes, and event rates in participants with propionic acidemia (PA).

This 3-part, Phase 1/2 study is designed to characterize the safety, tolerability, and pharmacological activity (as assessed by biomarker measurements) and to determine the selected dose of mRNA-3927 in participants with genetically confirmed propionic acidemia (PA). After establishing a dose with an acceptable safety and pharmacodynamic (PD) response for participants ≥1 year of age in Part 1, participants will be enrolled in Part 2 (which will serve as the pivotal study) to allow for determination of the efficacy, safety, and PD of mRNA-3927. Part 3 will evaluate the safety, efficacy and PD response of mRNA-3927 in infants (\<1 year of age).

To obtain short-term and long-term clinical safety information, in pediatric and adult patients with PA and MMA treated with Carbaglu®.

This is a prospective mixed-design study focused on the long-term management of propionic aciduria (PA) and methylmalonic aciduria (MMA) with N-carbamylglutamate (NCG) maintenance therapy. Treatment characteristics, clinical outcomes, and healthcare utilization data of patients diagnosed PA or MMA treated \>6 months therapy with NCG are collected at baseline, 12 months, 18 months, 36 months and 54 months. Qualitative interviews with adult patients and caregivers are conducted \>6 months after study enrollment to gain a better understanding of the disease burden and the treatment burden of patients and their families.