This is a study of amlitelimab for the treatment of participants with moderate-to-severe asthma. The study will have a double-blind treatment period until Week 24 for each participant and an open-label treatment period where each participant will receive open-label amlitelimab from Week 24 onwards. The purpose of this study is to evaluate long-term safety, tolerability, and efficacy of amlitelimab for the treatment of adult participants with moderate-to-severe asthma who have previously been enrolled and completed the treatment period of the parent study. The study duration will be up to 156 weeks. The treatment duration will be up to 144 weeks. The number of visits will be 18.

The duration of the study for each participant will be up to 156 weeks.

Inclusion Criteria:

• Participants with moderate-to-severe asthma who completed the treatment period of the parent study per protocol
• Participants on background dose with medium-to-high doses of ICS therapy (≥500 µg of fluticasone propionate daily or comparable ICS dosage up to a maximum of 2000 µg/day of fluticasone propionate or clinically comparable) in combination with a second or third controller (eg, LABA, LTRA, LAMA, methylxanthines), with or without OCS (up to a maximum of 15 mg prednisone or equivalent daily or 30 mg every other day) as maintained during the parent study in which they participated Note for Japan: participants must be on ≥400 μg of fluticasone propionate daily or equivalent.
• Contraception for male and female participants;

For female participants:

• incapable of becoming pregnant
• not pregnant or breast feeding
• not to donate or cryopreserve eggs for female participants For male participants
• No sperm donation or cryopreserving sperms

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

• Chronic lung disease other than asthma
• Participants who developed a new medical condition or a change in status of an established medical condition or require a new treatment or medication prior to enrollment, which (per Investigator's medical judgment) would adversely affect the participation in this study or would require permanent IMP discontinuation
• Current smoker or active vaping of any products and/or marijuana smoking
• Prescription drug or substance abuse, including alcohol, considered significant by the Investigator
• Any new development with the participant's disease or condition or any significant laboratory test abnormality during the parent study that, in the opinion of the Investigator, may present an unreasonable risk for the participant
• Sensitivity to any of the study interventions, or components thereof, or drug or other allergy that, in the opinion of the Investigator, contraindicates participation in the study
• Individuals accommodated in an institution because of regulatory or legal order; prisoners or participants who are legally institutionalized
• Participant not suitable for participation, whatever the reason, as judged by the Investigator, including medical or clinical conditions, or participants potentially at risk of noncompliance to study procedures
• Participants are employees of the investigative site or other individuals directly involved in the conduct of the study, or immediate family members of such individuals

The above information is not intended to contain all considerations relevant to a 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

This study will have a double-blind treatment period and an open-label treatment period after week 24