Primary Objective:

• To describe the clinical features and their severity at the time of diagnosis and their evolution over time in patients with confirmed chronic visceral and chronic neurovisceral forms of ASMD
• To describe Clinician-Reported Outcomes (ClinROs) and Patient-Reported Outcomes (PROs) at enrollment and their evolution over time; disease severity at the time of diagnosis and its evolution over time

Secondary Objectives:

• To describe abnormal values in laboratory parameters and all values of specific clinical and imaging assessments at the time of diagnosis and their evolution over time
• To study the use and applicability towards validation of a newly developed ASMD disease severity scoring system
• To study the use and applicability towards validation of a newly developed ASMD PRO tool
• To describe ASMD-related disease burden among patients with ASMD, caregivers, and healthcare resource utilization
• To describe the association between patient demographics (eg, age, gender, race, Ashkenazi ancestry) and genotype with selected clinical features in patients with confirmed chronic visceral and chronic neurovisceral forms of ASMD

Estimated average of study duration (for each patient) is 2 years

Inclusion criteria :

• Patients with confirmed diagnosis of chronic forms of ASMD based on 1) a clinical diagnosis consistent with chronic visceral ASMD (ie, NPD B) or chronic neurovisceral ASMD (ie, NPD B variant or intermediate NPD A/B) and 2) deficient enzymatic activity (as measured in peripheral leukocytes, cultured fibroblasts, lymphocytes, or DBS) or presence of 2 pathogenic SMPD1 mutations,
• The patient (or patient's legal guardian) must provide signed informed consent.

Exclusion criteria:

Patients suspected or diagnosed with infantile onset ASMD (ie, NPD A, with progressive developmental delay, or presence of any combination of R498L, L304P, and P333fs*52 genotypes, if available),

• Patients having received or receiving an investigational drug,
• Patients receiving any ASMD specific ERT,
• Patients with poor general condition that would not be able to undergo study assessments as per investigator's clinical judgment.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org