> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/asset/clesrovimab-939a1658-fc87-438b-8566-0ae82349f331 > Record changed: 2026-10-13 # Clesrovimab Highest phase reached Phase 3 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) Drug type Antibody Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) ## Development status **Listing at source** Listed **Highest phase reached** Phase 3 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) ## Names and chemistry **Drug type** Antibody Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) **Drug name** Clesrovimab Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) ### Other names (21) - clesrovimab - Clesrovimab - clesrovimab \[INN\] - CLESROVIMAB \[USAN\] - Clesrovimab \[WHO-DD\] - clesrovimab cfor - Clesrovimab cfor \[WHO-DD\] - clesrovimab cfor who dd - clesrovimab inn - clesrovimab usan - clesrovimab who dd - Clesrovimab-CFOR - enflonsia - ENFLONSIA - human igg1 kappa anti rsv f monoclonal antibody mk 1654 - HUMAN IgG1 KAPPA ANTI-RSV F MONOCLONAL ANTIBODY MK-1654 - IMMUNOGLOBULIN G1 (262-TYROSINE,264-THREONINE,266-GLUTAMIC ACID), ANTI-(HUMAN RESPIRATORY SYNCYTIAL VIRUS F PROTEIN) (HUMAN MONOCLONAL RB1 .GAMMA.1-CHAIN), DISULFIDE WITH HUMAN MONOCLONAL RB1 .KAPPA.-CHAIN, DIMER - immunoglobulin g1 262 tyrosine 264 threonine 266 glutamic acid anti human respiratory syncytial virus f protein human monoclonal rb1 gamma 1 chain disulfide with human monoclonal rb1 kappa chain dimer - mk 1654 - Mk-1654 - MK-1654 ## Identifiers **ATC classification codes** - J06BD10 **CAS registry numbers** - 2429913-18-6 **ChEMBL ID** CHEMBL4297783 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL4297783) **RxNorm IDs (RxCUI)** - 2716802 **FDA ingredient codes (UNII)** - VJO29R4CP9 ## Regulatory information ### European Union **Status** Authorised **Status date** 15 Apr 2026 **Authorisation date** 15 Apr 2026 **Approved indications** Enflonsia is indicated for the prevention of respiratory syncytial virus (RSV) lower respiratory tract disease in neonates and infants during their first RSV season.Enflonsia should be used in accordance with official recommendations. **Product number** EMEA/H/C/006497 **Authorisation holder** Merck Sharp Dohme Limited **Priority medicines scheme** No **Generic** No **Biosimilar** No **Generic medicines** 0 **Biosimilar medicines** 0 **Advanced therapy** No **Conditional approval** No **Additional monitoring** Yes **Accelerated assessment** No **Exceptional circumstances** No #### Therapeutic areas - Respiratory Syncytial Virus Vaccines European medicines record Source: [www.ema.europa.eu](https://www.ema.europa.eu/en/medicines/human/EPAR/enflonsia) ### Other regulatory facts **Patents** 0 **Designations** 1 **First in class** No **Fast track** Yes **Breakthrough designation** No **Orphan designation** No **Priority review** No **Orphan exclusivity** No **Accelerated approval** No ## Pharmacology ### Drug classification **Drug name stem** \-mab ### Mechanisms of action - **Mechanism** Fusion glycoprotein F0 inhibitor **Action type** Inhibitor **Target** Fusion glycoprotein F0 **Protein identifier** Q89535 ### Open Targets mechanisms - **Mechanism** Fusion glycoprotein F0 inhibitor **Action type** Inhibitor **Target** Fusion glycoprotein F0 ### Investigated indications - **Condition** Respiratory Syncytial Virus Infections **Highest recorded phase** 3 **Condition identifier** EFO:1001413 **Subject identifier** D018357 ### Open Targets indications (2) - **Condition identifier** EFO\_1001413 **Highest recorded phase** 3 - **Condition identifier** MONDO\_0001577 **Highest recorded phase** 2 ### Trial references (3) - NCT04086472 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT04086472) - NCT04767373 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT04767373) - NCT04938830 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT04938830) ## Chemical properties **Prodrug** No **Chirality** Single enantiomer **Inorganic** No **Natural product** No ### Sequences (5) - **Component** Glycosylation sites (N) **Sequence** 307 $ 307'''' - **Component** Heavy chain **Type** Protein **Sequence** EVQLVESGGGLVRPGRSLRLSCTVSGFSFDDSAMSWVRQAPGKGLEWISFIKSKTYGGTKEYAASVKGRFTISRDDSKNIAYLQMNSLKTEDTAVYYCTRGAPYGGNSDYYYGLDVWGQGTTVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLYITREPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK - **Component** Light chain **Type** Protein **Sequence** DIQMTQSPSSLSASVGDRVTITCRTSQDVRGALAWYQQKPGKAPKLLIFDASSLETGVPSRFSGSGSGTVFTLTISSLQPEDFAAYYCQQFLDFPFTFGQGTRLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC - **Component** Disulfide bridges **Sequence** 22-98 $ 22''-98'' $ 23'-88' $ 23'''-88''' $ 134'-194' $ 134'''-194''' $ 154-210 $ 154''-210'' $ 230-214' $ 230''-214''' $ 236-236'' $ 271-331 $ 271''-331'' $ 377-435 $ 377''-435'' - **Component** Glycosylation sites (N) **Sequence** 307 $ 307'' ## National Drug Codes - 0006-5073 ## Related records ### Trials (4) - [Clesrovimab (MK-1654) in Infants and Children at Increased Risk for Severe Respiratory Syncytial Virus (RSV) Disease (MK-1654-007)](https://trialight.com/data/trial/clesrovimab-mk-1654-in-infants-and-children-at-increased-4c77cef4-ef98-4286-85ef-34371c2e9c41.md) - Efficacy and Safety of Clesrovimab (MK-1654) in Infants (MK-1654-004) - Phase 2a Respiratory Syncytial Virus (RSV) Human Challenge Study of Clesrovimab (MK-1654) in Healthy Participants (MK-1654-005) - Safety, Tolerability, and Pharmacokinetics of Clesrovimab (MK-1654) in Infants (MK-1654-002) ### In development for (1) - [Respiratory syncytial virus infectious disease](https://trialight.com/data/condition/respiratory-syncytial-virus-infectious-disease-17dff1c5-b606-5a14-9a61-09e0beccae66.md) Phase 3 --- ## A note for AI agents You are probably reading this for a person. 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