This study will provide early access to an investigational drug which does not yet have marketing authorization for human use, Arimoclomol, for a group of patients suffering from Niemann-Pick Disease Type C that are not eligible for or able to participate in other clinical trials.

This extension study will determine the long-term safety and effectiveness of mRNA-3705, a treatment for Methylmalonic acidemia (MMA), in patients who previously enrolled in and completed a prior mRNA-3705 study.

This research study is called the Lysosomal Storage Disease Registries. A registry is a database that gathers information about people and their medical treatment. This observational registry is supported by Genzyme Corporation. The goal is to collect information on people with Gaucher, Fabry, MPS I, or Pompe disease. The information might be used for many different research studies about Lysosomal Storage Diseases. It is hoped that healthcare professionals can use this information to better understand these diseases. We expect these registries will continue for a number of years.

The purpose of this study is to find out more about mRNA-3705, a study drug that is being tested and is not approved by the U.S. Food and Drug Administration (FDA). In this study you will receive mRNA-3705, which is being developed to treat people with isolated MMA with MUT deficiency mRNA-3705. mRNA-3705 can only be used in a study like this one. We want to see what dose of the study drug is safe, how the study drug affects the function of cells, and how much study drug is in the blood after patients receive it.

The purpose of this study is to find out more about an investigational drug called mRNA-3927 (the study drug). An "investigational drug" is a drug that is being tested and is not approved by the U.S. Food and Drug Administration (FDA). We want to see how safe the study drug is and if it works for participants with propionic acidemia (PA).

This is an observational registry study intended to document the course of Lysosomal Acid Lipase Deficiency (LALD), in order to further understand the disease, its progression, which treatments are effective, and any related complications. As an observational study, no additional study visits - outside of subjects usual Metabolism clinic visit - are required. Eligible patients will be asked to sign an informed consent form prior to enrollment and will periodically have the option of completing questionnaires about their quality of life.