Retatrutide

Retatrutide (LY-3437943) is an experimental drug for obesity developed by American pharmaceutical company Eli Lilly and Company. It is a triple glucagon hormone receptor agonist (GLP-1, GIP, and GCGR receptors).^[1] It has been shown to achieve a more than 17.5% mean weight reduction in adults without diabetes but with obesity or preobesity (overweight) during a phase 2 trial.^[2][3][4] In the trial, the participants who received the highest dose (12 mg) showed a mean weight reduction of 24.2% after 48 weeks.^[4]

Retatrutide

Clinical data
Other names	LY-3437943
Identifiers
IUPAC name L-tyrosyl-2-methylalanyl-L-glutaminylglycyl-L-threonyl-L-phenylalanyl-L-threonyl-L-seryl-L-alpha -aspartyl-L-tyrosyl-L-seryl-L-isoleucyl-2-methyl-L-leucyl-Lleucyl-L-alpha -aspartyl-L-lysyl-N6-(N-(19-carboxy-1-oxononadecyl)-L-gamma-glutamyl-2-(2-(2-aminoethoxy)ethoxy)acetyl)-L-lysyl-L-alanyl-L-glutaminyl-2-methylalanyl-L-alanyl-Lphenylalanyl-L-isoleucyl-L-alpha -glutamyl-L-tyrosyl-L-leucyl-L-leucyl-L-alpha -glutamylglycylglycyl-L-prolyl-L-seryl-L-serylglycyl-L-alanyl-L-prolyl-L-prolyl-L-prolyl-L-serinamide
CAS Number	2381089-83-2
UNII	NOP2Y096GV
ChEMBL	ChEMBL5095485
Chemical and physical data
SMILES CC[C@H](C)[C@H](NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](C)NC(=O)C(C)(C)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](C)NC(=O)[C@H](CCCCNC(=O)COCCOCCNC(=O)CC[C@H](NC(=O)CCCCCCCCCCCCCCCCCCC(=O)O)C(=O)O)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CC(C)C)NC(=O)[C@](C)(CC(C)C)NC(=O)[C@@H](NC(=O)[C@H](CO)NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CO)NC(=O)[C@@H](NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@@H](NC(=O)CNC(=O)[C@H](CCC(N)=O)NC(=O)C(C)(C)NC(=O)[C@@H](N)Cc1ccc(O)cc1)[C@@H](C)O)[C@@H](C)O)[C@@H](C)CC)C(=O)N[C@@H](CCC(=O)O)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCC(=O)O)C(=O)NCC(=O)NCC(=O)N1CCC[C@H]1C(=O)N[C@@H](CO)C(=O)N[C@@H](CO)C(=O)NCC(=O)N[C@@H](C)C(=O)N1CCC[C@H]1C(=O)N1CCC[C@H]1C(=O)N1CCC[C@H]1C(=O)N[C@@H](CO)C(N)=O
InChI InChI=1S/C221H342N46O68/c1-23-124(11)179(208(322)241-144(83-88-176(291)292)192(306)245-150(105-134-69-75-137(276)76-70-134)196(310)244-148(100-121(5)6)194(308)243-147(99-120(3)4)193(307)240-142(82-87-175(289)290)187(301)230-110-169(282)229-113-173(286)264-92-51-61-161(264)206(320)253-158(116-270)203(317)251-157(115-269)189(303)232-111-170(283)233-128(15)212(326)266-94-53-63-163(266)214(328)267-95-54-64-164(267)213(327)265-93-52-62-162(265)207(321)250-156(114-268)183(226)297)258-200(314)152(103-131-55-41-39-42-56-131)242-185(299)127(14)235-216(331)219(18,19)262-205(319)145(80-85-166(225)279)237-184(298)126(13)234-190(304)140(60-48-50-90-227-172(285)119-335-98-97-334-96-91-228-167(280)86-81-146(215(329)330)236-168(281)65-45-37-35-33-31-29-27-25-26-28-30-32-34-36-38-46-66-174(287)288)238-191(305)141(59-47-49-89-222)239-198(312)154(107-177(293)294)247-195(309)149(101-122(7)8)256-218(333)221(22,109-123(9)10)263-211(325)180(125(12)24-2)259-204(318)160(118-272)252-197(311)151(106-135-71-77-138(277)78-72-135)246-199(313)155(108-178(295)296)248-202(316)159(117-271)254-210(324)182(130(17)274)260-201(315)153(104-132-57-43-40-44-58-132)249-209(323)181(129(16)273)257-171(284)112-231-188(302)143(79-84-165(224)278)255-217(332)220(20,21)261-186(300)139(223)102-133-67-73-136(275)74-68-133/h39-44,55-58,67-78,120-130,139-164,179-182,268-277H,23-38,45-54,59-66,79-119,222-223H2,1-22H3,(H2,224,278)(H2,225,279)(H2,226,297)(H,227,285)(H,228,280)(H,229,282)(H,230,301)(H,231,302)(H,232,303)(H,233,283)(H,234,304)(H,235,331)(H,236,281)(H,237,298)(H,238,305)(H,239,312)(H,240,307)(H,241,322)(H,242,299)(H,243,308)(H,244,310)(H,245,306)(H,246,313)(H,247,309)(H,248,316)(H,249,323)(H,250,321)(H,251,317)(H,252,311)(H,253,320)(H,254,324)(H,255,332)(H,256,333)(H,257,284)(H,258,314)(H,259,318)(H,260,315)(H,261,300)(H,262,319)(H,263,325)(H,287,288)(H,289,290)(H,291,292)(H,293,294)(H,295,296)(H,329,330)/t124-,125-,126-,127-,128-,129+,130+,139-,140-,141-,142-,143-,144-,145-,146-,147-,148-,149-,150-,151-,152-,153-,154-,155-,156-,157-,158-,159-,160-,161-,162-,163-,164-,179-,180-,181-,182-,221-/m0/s1 Key:MLOLQJNKXBNWFW-JMUPIODPSA-N

Chemistry

Retatrutide is a peptide with the following amino acid sequence^[5]

YA¹QGTFTSDYSIL²LDKK⁴AQA¹AFIEYLLEGGPSSGAPPPS³

where letters with superscripted numbers refer to the following chemical modifications:

1. "A¹" refers to 2-aminoisobutyric acid (Aib).
2. "L²" refers to leucine modified with an α-methyl substituent (MeL, 2-methylleucine).
3. "S³" refers to L-serinamide (L-serine with the carboxylic acid group replaced with a carboxamide).
4. "K⁴" refers to L-lysine with the amino group at position 6 modified with a side chain; specifically, (AEEA)-(γ-Glu)-(C20 diacid) (where AEEA is 2-[2-(2-aminoethoxy)ethoxy]acetic acid, commonly used as a spacer group in synthetic peptides).