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Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/asset/efimosfermin-alfa-15827437-369a-482c-a32a-f16bd0d25c09 > Record changed: 2026-10-13 # Efimosfermin alfa Highest phase reached Phase 2 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) Drug type Protein Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) ## Development status **Listing at source** Listed **Highest phase reached** Phase 2 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) ## Names and chemistry **Drug type** Protein Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) **Drug name** Efimosfermin alfa Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) ### Other names (20) - bos 580 - BOS-580 - efimosfermin alfa - Efimosfermin alfa - Efimosfermin Alfa - efimosfermin alfa \[INN\] - EFIMOSFERMIN ALFA \[USAN\] - Efimosfermin alfa \[WHO-DD\] - efimosfermin alfa inn - efimosfermin alfa usan - efimosfermin alfa who dd - Fc fragment of human immunoglobulin G1 (1-227) \[Homo sapiens IGHG1\*03 (hinge (1-10), CH2 L14>A, L15 >A (11-120), CH3 (121-226), CHS (226-227))\] fused via peptide linker 228GS229 to human fibroblast growth factor 21 (FGF-21) fragment 33-209 \[Q55 >C252, R105 >K302, G148 >C345, K150 >R347, P158 >S355, S195 >A392, P199 >G396, G202 >A399\]-variant (230-406 in the current sequence); dimer (6-6', 9-9')-bisdisulfide, produced in Chinese hamster ovary (CHO) cells, cell line CHO-DG44, glycoform alfa - fc fragment of human immunoglobulin g1 1 227 homo sapiens ighg1 03 hinge 1 10 ch2 l sup 14 sup a l sup 15 sup a 11 120 ch3 121 226 chs 226 227 fused via peptide linker sup 228 sup gs sup 229 sup to human fibroblast growth factor 21 fgf 21 fragment 33 209 q sup 55 sup c sup 252 sup r sup 105 sup k sup 302 sup g sup 148 sup c sup 345 sup k sup 150 sup r sup 347 sup p sup 158 sup s sup 355 sup s sup 195 sup a sup 392 sup p sup 199 sup g sup 396 sup g sup 202 sup a sup 399 sup variant 230 406 in the current sequence dimer 6 6 9 9 bisdisulfide produced in chinese hamster ovary cho cells cell line cho dg44 glycoform alfa - Immunoglobulin G1 \[14-alanine,15-alanine\] (human γ1-chain C region C-terminal fragment) fusion protein with peptide linker (GS) fusion protein with 5-181-fibroblast growth factor 21 \[27-cysteine,120-cysteine\] (human), dimer - immunoglobulin g1 14 alanine 15 alanine human γ1 chain c region c terminal fragment fusion protein with peptide linker gs fusion protein with 5 181 fibroblast growth factor 21 27 cysteine 120 cysteine human dimer - llf 580 - LLF-580 - llf580 - Llf580 - LLF580 ## Identifiers **CAS registry numbers** - 2765640-39-7 **ChEMBL ID** CHEMBL6068114 Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL6068114) **FDA ingredient codes (UNII)** - Y114QW0F16 ## Regulatory information ### Other regulatory facts **Patents** 0 **Designations** 1 **First in class** No **Fast track** No **Breakthrough designation** No **Orphan designation** No **Priority review** No **Orphan exclusivity** No **Accelerated approval** No ## Pharmacology ### Drug classification **Drug name stem** ef-; -ermin ### Investigated indications - **Condition** Obesity **Highest recorded phase** 1 **Condition identifier** EFO:0001073 **Subject identifier** D009765 ### Open Targets indications (5) - **Condition identifier** EFO\_0001073 **Highest recorded phase** 1 - **Condition identifier** EFO\_0003095 **Highest recorded phase** 3 - **Condition identifier** MONDO\_0005347 **Highest recorded phase** 1 - **Condition identifier** MONDO\_0007027 **Highest recorded phase** 3 - **Condition identifier** MONDO\_0013209 **Highest recorded phase** 1 ### Trial references - NCT03466203 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT03466203) ## Chemical properties **Prodrug** No **Chirality** Single enantiomer **Inorganic** No **Natural product** No ### Sequences (3) - **Component** Sequence **Type** Protein **Sequence** DKTHTCPPCPAPEAAGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGKGSDSSPLLQFGGQVRQRYLYTDDACQTEAHLEIREDGTVGGAADQSPESLLQLKALKPGVIQILGVKTSRFLCQKPDGALYGSLHFDPEACSFRELLLEDGYNVYQSEAHGLPLHLPCNRSPHRDPASRGPARFLPLPGLPPALPEPPGILAPQPPDVGSSDPLAMVGGSQARSPSYAS - **Component** Glycosylation sites (N) **Sequence** 77 $ 77'' - **Component** Disulfide bridges **Sequence** 6-6' $ 9-9' $ 41-101 $ 41'-101' $ 147-205 $ 147'-205' $ 252-345 $ 252'-345' $ 300-318 $ 300'-318' ## Related records ### Trials (8) - [A Clinical Study to Investigate the Safety and Tolerability of Efimosfermin Alfa Injection in Participants With Known or Suspected F2- or F3-stage MASH](https://trialight.com/data/trial/a-clinical-study-to-investigate-the-safety-and-tolerability-0bcf0f7b-2684-401c-9570-8ed8020dd8a4.md) - [A Pivotal Clinical Study to Investigate Efimosfermin Alfa in Participants With Biopsy-confirmed F2- or F3-stage MASH](https://trialight.com/data/trial/a-pivotal-clinical-study-to-investigate-efimosfermin-alfa-in-29de1da1-063e-4e81-8e0a-3e33b040bda2.md) - [A Pivotal Clinical Study to Investigate the Safety and Efficacy of Efimosfermin Compared With Placebo in Adult Participants With Compensated Cirrhosis Due to Metabolic Dysfunction-associated Steatohepatitis (MASH)](https://trialight.com/data/trial/a-pivotal-clinical-study-to-investigate-the-safety-and-615aa1a9-45ff-4b7d-8459-0d17f85cf323.md) - A Study of Efimosfermin Alfa in Adults With Hepatic Impairment - A Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Immunogenicity of Efimosfermin Alfa Administered as a Single Dose to Healthy Participants of Chinese, Japanese, and White/European Ancestry - A Study to Investigate Safety and Efficacy of Efimosfermin Compared With Placebo in Adult Participants With Compensated Cirrhosis Due to Metabolic Dysfunction-associated Steatohepatitis (MASH) - [A Study to Investigate the Safety and Efficacy of Efimosfermin Alfa Compared With Placebo in Adult Participants With Alcohol-related Liver Disease (ALD)](https://trialight.com/data/trial/a-study-to-investigate-the-safety-and-efficacy-of-91f539c9-56be-4516-ab19-4e536158d441.md) - Safety Study of LLF580 in Obese Volunteers ### In development for (2) - [Metabolic dysfunction-associated steatotic liver disease](https://trialight.com/data/condition/metabolic-dysfunction-associated-steatotic-liver-disease-beb92cb4-74bc-5e17-96f1-97aeed54ab35.md) Phase 3 - [Obesity disorder](https://trialight.com/data/condition/obesity-disorder-f3b57dc0-68ac-555c-8f13-0d81e595d9cb.md) Phase 1 --- ## A note for AI agents You are probably reading this for a person. 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