discovery of dpp-4 inhibitors as antidiabetic agents · 2019-11-04 · copyright © 2010 merck...
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Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Discovery of DPP-4 Inhibitors as Antidiabetic Agents
Tesfaye Biftu Merck & Co., Inc.
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• c. 1552 B.C. – 1st reference to Rx for polyuria by Hesy-Ra, 3rd Dynasty Ebers Papyrus
• c. 100 B.C. – The father of medicine in India, Susruta of the Hindus, diagnosed diabetes
• c. 30 B.C. ~ 50 A.D. – 1st clinical description of diabetes, Aulus Cornelius Celsus
• c. 150 A.D. – The name “diabetes” was first introduced from the Greek word for “siphon” by Aretaeus of Cappadocia
History of Diabetes
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• Discovery of Insulin (1921) – An Instant Hit – First Human Clinical Trial 1922 – Noble Price 1923 Benting & MacLoed – Commercial Production 1923 Eli Lilly – First Total Synthesis 1965 Chinese Team
• Discovery of Glucagon (1923) – Largely Unnoticed – Sequenced in 1957 – Rediscovered in 1970’s for its role in diabetes
• Discovery of Incretins – Gastrointestinal Hormones – 1932 The term “incretin” was first used – 1970 GIP was isolated – 1982 GLP-1 was sequenced
……….continued
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• 2000: 171 million cases worldwide; 2030: 366 million cases predicted
• >90% is Type 2 diabetes: obesity is a major risk factor
Diabetes is a Growing Worldwide Epidemic
The Americas 2000: 33 million 2030: 66.8 million
Europe 2000: 33.3 million 2030: 48 million
Middle East 2000: 15.2 million 2030: 42.6 million
Africa 2000: 7 million 2030: 18.2 million
Asia and Australia 2000: 82.7 million 2030: 190.5 million
<3 3-5 6-8 >8
Prevalence (%) in persons 35-64 yrs
WHO
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<4% 4-4.9% 6+%
1994 2004
5-5.9%
Ø 20,800,000 People in US (7%) have diabetes (2005) Ø 6th Leading cause of death in US (2002), by death certificate Ø >90% Type 2, associated with metabolic syndrome
Taken from CDC diabetes website: http://www.cdc.gov/diabetes
missing data
Trends among U.S. Adults: 1994 to 2004
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Current Medications for Treatment of Diabetes
Safer and more effective medications are needed
Sulfonylureas Meglitinides Metformin Thiazolidinediones α-Glucosidase inhibitors Insulin
Hypoglycemia, weight gain Hypoglycemia, weight gain GI intolerance Edema, weight gain GI intolerance Hypoglycemia, weight gain
Drug Class Side Effects
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Role of Active GLP-1 and GIP in Glucose Homeostasis
• Glucagon-Like-Peptide (GLP-1) and Glucose-Dependent-Insulotropic-Polypeptide (GIP) are secreted in response to food intake (glucose-dependent mechanism)
• GLP-1 and GIP - (↑)stimulate insulin biosynthesis & secretion
• GLP-1 inhibits - (↓) glucagon secretion
• GLP-1 and GIP - (↓)lower blood sugar level
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…. but Active GLP-1 (or GIP) is Cleaved Rapidly by DPP-4
GLP-1 (Active) HA EGTFTSDVSSYLEGQAAKEFIAWLVKGR-NH2
GLP-1 (Inactive) EGTFTSDVSSYLEGQAAKEFIAWLVKGR-NH2
DPP-4 t½ ~ 1 min Inhibit
Stabilize
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Dipeptidyl Peptidase IV (DPP-4)
• First Isolated from rat liver in 1966
• Identical to CD26, a marker for activated T cells
• Its role in energy homeostasis was discovered which led to the first patent application in 1996
• Cell surface serine dipeptidase belonging to the prolyl oligopeptidase family
• Widely expressed, and has Specificity for P1 Pro >> Ala
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N
O
SNH2
NS
I
O
O
QPP Selective DPP-8/9 Selective
N
OMeMe
NH2
DPP-4 Selective
DPP-9 > 100,000 11,000 55
DPP-8 69,000 22,000 38
FAP > 100,000 > 100,000 > 100,000
DPP-4 27 1900 30,000
PEP > 100,000 > 100,000 > 100,000
QPP/DPP-2 > 100,000 19 14,000
APP > 100,000 > 100,000 > 100,000
prolidase > 100,000 > 100,000 > 100,000
IC50, nM Enzyme
N
ONH2
NN
N
CF3
F
FSelective Inhibitors
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2 wk. Rat Toxicity QPP
Selective DPP-8/9
Selective DPP-4
Selective
Alopecia ü
Thrombocytopenia ü
Reticulocytopenia ü ü
Enlarged spleen ü
Mortality ü
Acute dog toxicity
Bloody diarrhea ü
G. Lankas, et al., Diabetes 2005, 54, 2988
Comparative Toxicity Study
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Potential Importance of Selective Inhibition for the Treatment of Type 2 Diabetes
• Conclusion – “Off-target” peptidase inhibition (i.e. inhibition of other DPP family
peptidases such as DPP8/9) can produce severe toxicity in preclinical species
• Variables that may determine degree of toxicity – Cell penetration
• Unlike DPP-4, DPP8/9 are intracellular proteins
– Extent of inhibition of DPP8 and/or DPP9 • Not known if inhibition of both enzymes
(or how much) is required to produce toxicities
– Intraspecies differences in DPP8/9 inhibition from Demuth et al. Biochim. Biophys. Acta 2005, 1751, 33
DPP-4
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DPP-4 Inhibitor Program - Objective Identify a potent and selective DPP-4 inhibitor for the
treatment of type 2 diabetes mellitus with the following characteristics:
• >1000-fold selectivity over other proline peptidases, especially DPP-8 and DPP-9
• Half-life suitable for BID or preferably QD dosing
• Structure lacking reactive electrophile as a serine trap, e.g.,
N
OHN
X
CN
RN
OH2N
R
B(OH)2
R'
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Common Lead Discovery Methods
• Biological screening of compounds
• Substrate or active-structure based design
• Enzyme – inhibitor crystal structure
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• β-Amino acid proline amides
IC50 = 1.9 µM
• β-Amino piperazines
IC50 = 11 µM H2NN
N
O
NH
NHSO2Me
N
HNO
Cl
OO
NH
ONH2
Screening Leads
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Radioactivity Recovered in 24 hrs (% Dose)
Collection Period Intravenous Oral Bile 28.3 ± 2.6% 38.2 ± 4.7% Urine 18.1 ± 2.0% 14.0 ± 4.2% Feces 1.0 ± 0.2% 1.4 ± 0.6% Total 47.4 ± 3.9% 54.6 ± 4.9%
N
NH
ONH2
F
T
Recovery of Radioactivity after IV (1 mg/kg) or Oral (2 mg/kg) Administration to Rats
Y. Teffera
PK Rat: • high clearance (>150 mL/min/kg) and • short half-life.
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Microsomes: piperazine ring oxidation. Hepatocytes: Conjugation of the primary amino group (glucuronic acid and glucose). Oxidation of the piperazine, the phenyl and the fluoro-phenyl rings. Glutathione conjugation on the fluoro-phenyl ring; d) amide bond hydrolysis. Bile of PO treated rats: carbamoyl glucuronide conjugate on the piperazine ring. Glutathione conjugation of the fluoro-phenyl ring, piperazine ring oxidation, and N-glucuronidation of the primary amine were also observed. Bile of IV treated rats: Glutathione conjugation on the fluoro-phenyl ring, piperazine and phenyl ring oxidation, and N-glucuronidation of the primary amine. Urine of PO treated rats: Acid formed by the de-ethylation and oxidative de-amination of the piperazine ring. Oxidation of the piperazine ring, glucuronidation of the primary amine, and amide bond hydrolysis were also observed. Urine of IV treated rats: excreted mainly parent compounds
Metabolites identified in microsomes, hepatocites, and bile of PO/IV treated rats
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N
X = NH, O
ONH2
F
Efforts made to stabilize metabolism
N
N
ONH2
F
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Bicyclic Piperazine Replacements
N
NN
R"
R
R'
N
N
NR"
R
R'
N
NO
R
N
NN
NR
R'
NN
N
R"
R
R'
NN
O
R'
RN
ON
R
N
O
NR N
ON
R
NR
N
NR
N
N
NRN
N
NR
NNRN
NR
N
N
NR
N
N
SR
N
S
NR
N
N
OR
N
N
NR
NN N
NR
NN
NN
R
NN
NR
NN
N
R
NN
N
R
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MK-0431 = JANUVIA™ (sitagliptin phosphate)
Left Hand Side SAR
N
ONH2
NN
N
CF3
R
D. Kim, et al., J. Med. Chem. 2005, 48, 141
Rat PK
R DPP-4 IC50 Clp t½ Frat (nM) (mL/min/kg) (h) (%)
3,4-diF 130 51 1.8 44
2,5-diF 27 43 1.6 50
2,4,5-triF 18 60 1.7 76 100
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Sitagliptin: In Vitro Potency and Selectivity N
ONH2
NN
N
CF3
F
FF
DPP-9
DPP-8
FAP
DPP-4
DPP-6
PEP
QPP/DPP-2
APP
prolidase
not active
DPP-4 Gene Family
Other Proline Specific Enzymes
IC50, (nM)
> 100000
48000
> 100000
> 100000
18
> 100000
> 100000
> 100000
not active
Selectivity Ratio
> 5000
2700
> 5000
> 5000
1
> 5000
> 5000
> 5000
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
PK Properties of Sitagliptin 1 mg/kg IV, 2 mg/kg PO
Clp Vd t½ PO AUCnorm PO Cmax F species (mL/min/kg) (mL/kg) (h) (µM·h/mpk) ( µ M ) ( % )
M o u s e 6 4 3 . 8 0 . 8 0 . 4 1 0 . 5 1 6 1
R a t 6 0 6 . 4 1 . 7 0 . 5 2 0 . 3 3 7 6
D o g 6 . 0 9 . 0 4 . 9 8 . 3 2 . 2 1 0 0
M o n k e y 2 8 2 . 3 3 . 7 1 . 0 0 . 3 3 6 8
N
ONH2
NN
N
CF3
F
FF
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Pharmacodynamics of Sitagliptin: OGTT in Lean Mice
Dose, mg/kg [sitagliptin], nM
0.1 19
0.3 52
1 190
3 600 Mouse DPP-4: IC50 = 69 nM
Glucose AUC DPP-4 Inhibition (uncorrected)
Active GLP-1
20 min post Glucose, 80 min post Compound
0
20
40
60
80
100
0 0.1 0.3 1 3
Glu
cose
AU
C, %
veh
icle
L-224715, mg/kg
0
2
4
6
8
0 0.1 0.3 1 3
Pla
sma
[GLP
-1] in
tact, p
M
L-224715, mg/kg
0
20
40
60
80
100
0 0.1 0.3 1 3
Pla
sma
DP
-IV %
inhi
bitio
n(u
ncor
rect
ed)
L-224715, mg/kgSitagliptin, mg/kg Sitagliptin, mg/kg
Sitagliptin, mg/kg
DPP-4 Inhibition
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Diabetic Mice
Chronic Efficacy with a Sitagliptin Analog in Mice Restoration of Pancreatic Islet β Cells
Diabetic Mice + Sitagliptin analog Lean Control Mice
Islets from HFD/STZ mice +/- 10 weeks of treatment with sitagliptin analog
Green: Insulin-producing β cell Red: Glucagon-producing α cell
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JANUVIATM
(sitagliptin)
Launched, Oct. 2006 N
ONH2
NN
N
CF3
F
FF
H3PO4 H2O
• Selective inhibition of DPP-4, in particular with respect to DPP-8 and/or DPP-9, provides an improved safety profile in preclinical species.
• Sitagliptin is a potent and selective DPP-4 inhibitor, very well tolerated in pre-clinical toxicity studies and in human clinical trials.
• In patients with type 2 diabetes, once daily administration of sitagliptin stabilizes active GLP-1 and GIP, reduces glucose excursion, enhances insulin levels, suppresses glucagon levels, and improves glycemic control.
• JANUVIA™ (sitagliptin) was approved by the FDA as a new treatment for type 2 diabetes.
For more info: www.januvia.com
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Back-up Objective
Identify a specific DPP-4 inhibitor as a back-up to sitagliptin
• Potency equivalent to or better than sitagliptin
• Increased half-life suitable for QD dosing
• Structural diversity
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α-Amino Acid Series Revisited
• Allo isomer is ~10-fold more toxic than threo
• Incorporate “threo” bias into α-amino acid series?
threo Ile-thiazolidide
N
O
SNH2
MeMe
N
O
SNH2
MeMe
allo Ile-thiazoldide
Enzyme IC50 (nM) IC50 (nM)
DPP-4 440 460 QPP 14,000 18,000
DPP-8 2,200 220 DPP-9 1,600 320
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N
O
SNH2
MeMe
Enzyme IC50 (nM)
DPP-4 420 QPP 14,000
DPP-8 2,200 DPP-9 1,600
J. Xu et al. Bioorg. Chem. Med. Lett. 2005, 15, 2533; S. D. Edmondson et al., J. Med. Chem. 2006, 49, 3614
β-Substituted Phenylalanine Derivatives
N
O
NH2
Me
FF
Enzyme IC50 (nM)
DPP-4 64 QPP 2,700
DPP-8 88,000 DPP-9 86,000
Rat PK Clp 8.6
t1/2 (h) 2.2 F (%) 85
hERG IC50 = 1.1 µM
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N
O
SNH2
MeMe
Enzyme IC50 (nM)
DPP-4 420 QPP 14,000
DPP-8 2,200 DPP-9 1,600
β-Substituted Phenylalanine Derivatives
N
O
NH2
Me
FF
Enzyme IC50 (nM)
DPP-4 64 QPP 2,700
DPP-8 88,000 DPP-9 86,000
Rat PK Clp 8.6
t1/2 (h) 2.2 F (%) 85
hERG IC50 = 1.1 µM
• Optimization Goals
– Increase potency and selectivity
– Decrease ion channel binding
– Maintain good oral bioavailability
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N
O
SNH2
MeMe
Enzyme IC50 (nM)
DPP-4 420 QPP 14,000
DPP-8 2,200 DPP-9 1,600
β-Substituted Phenylalanine Derivatives
N
O
NH2
Me
FF
Enzyme IC50 (nM)
DPP-4 64 QPP 2,700
DPP-8 88,000 DPP-9 86,000
Rat PK Clp 8.6
t1/2 (h) 2.2 F (%) 85
hERG IC50 = 1.1 µM
N
O
NH2N
N O
N
N
Me
Me
FF
Enzyme IC50 (nM)
DPP-4 8.8 QPP ~100,000
DPP-8 >100,000 DPP-9 >100,000
Rat PK Clp 2.8
t1/2 (h) 1.6 F (%) 100
hERG IC50 = >100 µM
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α-Amino Amide Back Up
• Criteria ✔ Potency equivalent to or better than sitagliptin – Increased t1/2 ✔ Potential for balanced renal/hepatic clearance ✔ Structural diversity
• Potential Liabilities – Modest QTc prolongation in CV dog
• Strategy – Position as an insurance back-up, should unexpected safety
issues arise with sitagliptin – Bulk drug prepared for 14-wk safety studies
Ø Identify an additional back up compound lacking QTc liability
N
O
NH2N
N O
N
N
Me
Me
FF
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Active-Structure Based Design
• Sitagliptin is a triazolopyrazine
• Triazolopyrazines are reported as bioisosters of amides
N
N
N
O
O
N
N TL, 41, (2000) 4533 & Ann Rep Med Chem
F
F
N
O
NN
N
CF3
NH2F
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N N
ON
N
ONN
O
IC50, nM 160 89 14
R R R
DPP-4
R = Di-Fluoro phenyl β-AA series
F
F
N
O
NN
N
CF3
NH2
R = H, IC50 = 27 nMR = Me, IC50 = 7.2 nM
R
F
F
N
O
NH
O
NH2
R = H, IC50 = 140 nMR = Me, IC50 = 89 nM
R
Design
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Activity vs. Stereochemistry
F
F
N
O
NH
ONH2
F
F
N
O
NH
ONH2
F F
DPP-4 IC50 = 6.6 nM DPP-4 IC50 = 150nM
**(R) (S)
F
F
N
O
NH
ONH2
F
F
N
O
NH
ONH2
F F
DPP-4 IC50 = 67,000 nM DPP-4 IC50 = 2,300 nM
(R) (S)
(R) (R)
(S) (S)
F
F
N
O
NH
ONH2
F
(R)
F
F
N
O
NH
ONH2
F
DPP-4 IC50 = 403 nM
DPP-4 IC50 = 140 nM
Activity: R,R > R,S > S,S > S,R
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R DPP-4 QPP DPP8 (nM) (nM) (nM)
H 0.91 17,000 21,000
2-Me 0.26 7,600 21,000
2-F 0.33 21,000 25,000
2-CF3 0.35 5,100 36,000
[2-Pyridine] 0.49 89,000 53,000
[2-Pyrrazole] 0.29 75,000 80,000
α-Substituted Aryl Diazepanone Derivatives
N
ONH2
F
FF
NH
O
R
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α-Alkylation of Diazepanone Derivatives
R DPP-4 (nM) QPP (nM) DPP8 (nM)
H 140 >100,000 82,000
Me 6.6 59,000 46,000
Et 16 47,000 13,000
CH2CF3 2.6 59,000 28,000
iBu* 25 35,000 79,000
CH2(cPr) 4.8 27,000 11,000
* N-methyl diazepanone
N
ONH2
F
FF
NH
OR
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N-Alkylation of Diazepanone Derivatives
R DPP-4 (nM)
QPP (nM)
DPP8 (nM)
H 6.6 59,000 46,000
Me 6.6 >100,000 21,000
CH2CH2OH 16 78,000 53,000
CH2CF3 19 56,000 43,000
iPr 44 18,000 >100,000
cPr 8 46,000 22,000
N
ONH2
F
FF
N
O
R
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5,6 or 7-Alkylated Diazepanone Derivatives
R DPP-4 (nM) QPP (nM) DPP8 (nM)
5α-Me/5β-Me 765/1050
6α-Me/6β-Me 13/33 56,000 70,000
6,6-di Me 140 17,000 26,000
7α –Me/7β-Me 15/400 73,000 79,000
7-CF3 140 >100,000 76,000
7-(2-F-Bn) 130 8,700 19,000
N
ONH2
F
FF
NH
O
56 7
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Phenyl Substituents
R DPP-4 (nM) QPP (nM) DPP8 (nM)
2-F 84 >100,000 27,000
2,5-Di F 7.4 >100,000 22,000
2,4,5-Tri F 2.6 59,000 28,000
N
ONH2
NH
O
R
CF3
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SAR Summary
N
O
N
ONH2
R'
RR
Loss of potency Not promising
Less potent
α isomer more potent than β
Less potent, Good selectivity Improved PK
α isomer more potent than β
R-isomer more potent than S-isomer Substituted benzyl/aryl most potent
Less potent Short half-life
R = 2,4,5 tri-F Best potency and PK
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Pharmacokinetics…
T1/2(h)
1
2
4.3
1.5
Clp(mL/min/kg)
88
94
93
51
N
O
NH
OCF3
Foral(%)
41%
94%
45%
49%
nAUC(µM h/mpk)
0.18
0.16
0.39
0.25
N
O
N
O
N
O
NH
O
N
O
NH
O
*PK parameters were obtained following a iv (1 mg/kg) or po (2 mg/kg) dose
Rat PK
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IC50 (nM) BU
IKr >90,000 Ca 11,000 Na ~50,000
Off-target Activity:
Potency and selectivity: IC50 (nM) BU
DPP-4 2.6 QPP 59,000 DPP8 28,000 DPP9 41,000 PEP >100,000 APP >100,000 Prolidase >100,000 FAP 23,000
N
ONH2
NH
OCF3
F
FF
Trifluroethyl Diazepanone Candidate
• Pharma services >10,000 nM except Ca channel (Ki=5.5 µM)
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Prot.Binding Clp Vd t½ PO AUCnorm PO Cmax F Species (% bound) (mL/min/kg) (L/kg) (h) (µM·h/mpk) (µM) (%)
Rat 89 94 12 1.9 0.157 0.085 36
Dog 91 18 11 8.9 2.19 0.522 95
Rhesus 90 53 18 5.4 0.15 0.162 20**
Human 91 [6-23]*
Oral Bioavailability
* Estimated ** Low %F due to first pass effect
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Stability in Liver Microsomes and Hepatocytes
Liver Microsomes at 1 µM, 1 mg/mL protein
Hepatocytes at 1 µM, 1 M cells/mL
0.0
20.0
40.0
60.0
80.0
100.0
0 10 20 30 40 50 60 70 Time (min)
% P
aren
t Rem
aini
ng
RLM DLM MLM HLM
0.0
20.0
40.0
60.0
80.0
100.0
0 20 40 60 80 100 120 Time (min)
% P
aren
t Rem
aini
ng
RLM DLM MLM HLM
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Pharmacodynamics…
Glucose AUC DP-IV inhibition (uncorrected)
Active GLP-1
Lean Mice, 0 min post Glucose, 70 min post Compound
Dose, mg/kg Plasma Level, nM
0.1 7.5
0.3 24.8
1 84.2
3 266 Mouse DP-IV: IC50 = 26.8 nM 0
2
4
6
8
10
12
0 0.1 0.3 1 3
Plas
ma
[GLP
-1] in
tact, p
M
L-001169872, mg/kg
0
20
40
60
80
100
0 0.1 0.3 1 3
Plas
ma
DP-
IV %
inhi
bitio
n(u
ncor
rect
ed)
L-001169872, mg/kg
0
20
40
60
80
100
0 0.1 0.3 1 3
Glu
cose
AU
C, %
veh
icle
L-001169872, mg/kg
Dose, mg/kg
Dose, mg/kg Dose, mg/kg
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Summary Results
• Structurally diverse – unique right hand side • Potent
• Selective
• Efficacious in OGTT model
• Excellent PK profile
• Metabolically stable in human microsome preparation
• 14 weeks rat and dog safety OK
Kept on hold as an insurance back-up to sitagliptin
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Most Common Lead Discovery Methods
• Biological screening of compounds
• Substrate or active-structure based design
• Enzyme – inhibitor crystal structure Crystal structure of DPP-4 reported in 2002
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Structure of DPP-4 Complex with val-pyr and Sitagliptin
N
NN
N
CF3
F
F
FONH2
Sitagliptin IC50 = 18 nM
NH2
N
O
Me
Me
Val-pyr IC50 = 1600 nM
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Computer Modeling
NH2
N
O
H-Bonding Salt Bridge
N
O NH2
F
FF
N
NN
F3C
IC50 = 4.4 nM
H-Bonding Salt Bridge
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
N
O NH2
F
F
F
N
NN
F3C
IC50 = 0.6 nM
H-Bonding Salt Bridge
No Room!!
N
ONH2
F
F
F
NN
N
CF3
Rotate
The Same Salt Bridge
New H-Bonds
Plenty of Room
Computer Modeling
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Rigid Analogs: A New Generation of DPP-4 Inhibitors
A
NH2
N
O
F
F
B
B
NO
H2N
AC
N
H2N
C
F
F
F
F
F
F
F
Best Fit
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Sitagliptin and Cyclohexylamine in the DPP-4 Active Site
F
F
NN
NN
CF3
NH2F
N
NH2 O
F
FF
SitagliptinIC50 = 18 nM
NN
N
CF3
F357Y547
S209
R358
E205
Y666
R125
E206
N710
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Phenyl Substituents
R DPP-4 (nM) QPP (nM) DPP8 (nM) IKr (nM)
2-F 84 >100,000 27,000 -
2,5-Di F 7.4 >100,000 22,000 63,000
2,4,5-Tri F 2.6 59,000 28,000 90,000
N
NH2
NH
ORCF3
OH
Tri-F pheny results in better H-bond and enhances potency
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Clp t½ PO AUCnorm PO Cmax F Species (mL/min/kg) (h) (µM·h/mpk) (µM) (%)
Rat 7.6 6.6 6.8 0.14 130 Dog 3.9 18 10.1 0.93 95 Rhesus 9.5 14 3.9 0.56 94
NH2
F
FN
NN
N
CF3
FEnzyme IC50 (nM)
DPP-4 21 QPP >100,000 DPP-8 >100,000 DPP-9 >100,000 IKr 40,000 Ca 12,000 Na >50,000
OGTT – maximum efficacious dose 1 mpk
Cyclohexylamine DPP-4 Inhibitor
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
?
5,6-Heterocycles: A Better Fit?
F
F
N
NH2F
CF3
F
F
NN
NN
CF3
NH2F
IC50 = 21 nM
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
H-bond acceptor H-bond donor
NH2
F
FN
F
R
Cyclohexylamine Derivatives
• Increasing selectivity: 3D QSAR Model
R DPP-4 QPP DPP-8 (nM) (nM) (nM)
H 6.6 67,000 1700
CF3 7.6 88,000 5800
Y. Gao, et al., Bioorg. Med. Chem. Lett. 2007, 17, 3877
heteroatoms and/or polar groups preferred
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
NH2
F
FN
F
R
Cyclohexylamine Derivatives
R DPP-4 QPP DPP-8 (nM) (nM) (nM)
H 6.6 67,000 1700
CF3 7.6 88,000 5800
R DPP-4 QPP DPP-8 (nM) (nM) (nM)
H 0.67 >100,000 5000
CF3 0.53 >100,000 4600
NH2
F
FN
F
N
NR
Y. Gao, et al., Bioorg. Med. Chem. Lett. 2007, 17, 3877
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Cyclohexylamine Derivatives
R DPP-4 QPP DPP-8 (nM) (nM) (nM)
H 0.67 >100,000 5000
CF3 0.53 >100,000 4600
NH2
F
FN
F
N
NR
Y. Gao, et al., Bioorg. Med. Chem. Lett. 2007, 17, 3877
• R = H – Poor PK (high Clp, low %F) – hERG IC50 = 37 µm
• R = CF3 – Good PK properties – hERG IC50 = 4.8 µM – ↑QTc in CV dog
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
N-Aryl Piperidines N
NH2
ArF
FF
Compound Ar DPP-4 DPP8/9 Cav1.2 Cyp2D6 t1/2 F (nM) (nM) (nM) (nM) (h) (%)
L-001331552 N
N
37 >59,000 27,000 950 0.46 98
L-001346262 N
N
N 31 >10,000 240 1,700 1.2 32
L-001427229 NN
N
NCF3
5.3 >100,000 960 110 4.9 87
L-001464016 N
N
NMe
1.9 >56,000 88 4,400 1.6 37
Ø Compounds with increased selectivity have poor PK
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Fused Imidazopyridines
Target IC50 (nM) IC50 (nM) IC50 (nM) IC50 (nM) DPP-4 330 51 8.3 15 QPP 23,000 >100,000 >100,000 19,000
DPP-8 >100,000 72,000 >100,000 >100,000 DPP-9 >100,000 8,400 >100,000 >100,000 Cav1.2 n.d. >100,000 >100,000 >100,000
Cyp2D6 n.d. 19,000 13,000 5,200
N
NH2
F
FF
NN
NN N
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
New Scaffold
• Potent, selective DPP-4 inhibitor
• Novel structure, distinct from other development candidates
• Multiple routes of clearance
• Human PK projections suggest QD dosing
F
FF
NH2
N
NN
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Summary
• Structurally diverse middle ring designed by collaboration between MedChem, Structural biology and modeling groups
• Potent
• Selective
• Efficacious in OGTT model
• Excellent PK profile
Promising novel lead for development of
a new generation of DPP-4 inhibitors
Copyright © 2010 Merck & Co., Inc., Whitehouse Station, New Jersey, USA All rights Reserved
Comparative Medicine Irene Capodanno Paul Cunningham Marcie Donnelly William Feeney
Judy Fenyk-Melody James Hausamann
Donald Hora Christian Nunes
Allison Parlapiano Gina Seeburger
Xiaolan Shen John Strauss
Kenneth Valerich Zuliang Yao
Medicinal Chemistry Wally Ashton
Tes Biftu Linda Brockunier Chuck Caldwell
Ping Chen Hong Dong
Scott Edmondson Dennis Feng Mike Fisher Ed Gonzalez Jiafang He
Dooseop Kim Gui-Bai Liang
Tony Mastracchio Bob Mathvink
Hyun Ok You Jung Park Emma Parmee Xiaoxia Qian Leah Reigle
Rosemary Sisco Liping Wang
Lan Wei Ann Weber
Matt Wyvratt Jinyou Xu
Metabolic Disorders Savita Jagpal Joanne Jiang
David Kuo Barbara Leiting
Zhihua Li Frank Marsilio David Moller
Reshma Patel Kelly Ann Pryor
Ranabir Sinha Roy Nancy Thornberry
Kenny Wong Joe Wu
Bei Zhang Lan Zhu BCAS
Larry Colwell Huaibing He
Dorothy Levorse Kathy Lyons
Karen Owens
Synthetic Service Phil Eskola
Mark Levorse Bob Frankshun
Amanda Makarewicz
Drug Metabolism Maria Beconi Adria Colletti
Varsha Didolkar David Evans
Chris Kochansky Sanjeev Kumar
David Liu Tony Pereira
Ralph Stearns Yohannes Teffera
Regina Wang Sherrie Xu Wenji Yin
In Vivo Pharmacology Ed Brady
George Eiermann Judy Gorski
Gerry Hickey Peggy McCann
Joe Metzger Alex Petrov
Dick Saperstein Alison Strack
Immunology/Rheumatology Jerry Di Salvo Ruth Kilburn Greg Koch
Elizabeth Nichols Eugene O’Neill
Linda Wicker
X-Ray & Modeling Giovanna Scapin
Sangita Patel Suresh Singh Ying-duo Gao
Acknowledgements