PCSK9, the short track road from discovery as drug target towards - - PowerPoint PPT Presentation

PCSK9, the short track road from discovery as drug target towards the clinic

Professor Gilles Lambert, PhD

Laboratoire Inserm U1188 Université de la Réunion Faculté de Médecine Saint Denis de la Réunion, France.

Faculty Disclosure

Declarat aration ion of non-fina financia cial l interests ests

• Affiliation:

Uni niver ersité sité de la Réunion nion and nd IN INSERM ERM

• Position :

Pro rofess essor

• r of Biochemis

emistry y and Cell Biolog

• gy
• Member of:

The he Eu Euro ropea ean n Ath theroscl rosclerosis

• sis Societ

ety y

Faculty Disclosure

I I have recei ceived ed resear search ch grants ts

A From Sanofi-Regeneron, Amgen, and Pfizer Inc. YES B From the Agence Nationale de la Recherche YES

II II I have been en a speaker r or particip cipant ant in accredit redited ed CME/ E/CP CPD

A From Sanofi-Regeneron, Amgen, and Pfizer Inc. YES B From PACE YES

III III I have been en a cons nsulta tant/st nt/stra rategic egic adviso sor

A For Sanofi-Regeneron, Amgen, and Pfizer Inc. YES B For PCSK9 Forum YES

IV IV I am a holder lder of (a) patent/share ent/shares/st s/stock ck own wnersh ships ps

A Related to presentation NO B Not related to presentation NO

Declarati ration

• n of fin

financi cial al in intere rests sts For the the la last t 3 years and the the subse bsequent quent 12 month ths: :

DISCOVERY OF PCSK9

5

The LDL Receptor

Two French Families With Autosomal Dominant Hypercholesterolemia

Abifadel et al. (2003) Nature Genetics

PCSK9: gain of function mutations

D H N S

LDL-C

F216L D374Y S127R

SP pro-domain catalytic domain C-terminal domain

Lambert G et al. (2009) Atherosclerosis

50 100 150 200

4 5 7 9

Ad-Null Ad-PCSK9

PCSK9 Expression Increases Circulating LDL Cholesterol Levels in Mice

Days post adenoviral infusion Plasma Total Cholesterol (mg/dL)

* * * * p<0,05 vs. Ad-null

Maxwell and Breslow (2004) Proc Natl Acad Sci USA Benjannet et al. (2004) J Biol Chem Park et al. (2004) J Biol Chem Lalanne et al. (2005) J Lipid Res

PCSK9: loss of function mutations

D H N S SP pro-domain catalytic domain C-terminal domain

Lambert G et al. (2009) Atherosclerosis

LDL-C

Y142X C679X R46L

Cardiovascular benefits of PCSK9 loss of function mutations

Frequency (%)

30 20 10 50 100 150 200 250 300 No Nonsense Mutation (N=3278) 50th Percentile 30 20 10 50 100 150 200 250 300 PCSK9142x or PCSK9679X (N=85)

Plasma LDL-C in Black Subjects (mg/dL)

No Yes 4 8 12

Coronary Heart Disease (%) PCSK9142x or PCSK9679X 88% reduction in the risk of CHD

Cohen J, et al. (2006) N Engl J Med 2006

Prospective study of plasma LDL-C levels and incidence

• f CHD according to the

presence or absence of a PCSK0142X or PCSK9679X allele (N=3278) taken from a longitudinal, biracial cohort study designed to assess subclinical and clinical atherosclerosis (N=15792)

PCSK9 Knockout Mice Have Decreased Plasma Cholesterol

Total Cholesterol (mg/dL)

*

25 25 50 50 75 75 10 100 12 125

Control PCSK9-KO (-/-)

Rashid et al. (2005) Proc Natl Acad Sci USA

* p<0,05 vs. Control

BIOLOGY OF PCSK9

PCSK9: the enzyme (proprotein convertase)

D H N S pro-domain catalytic domain C-terminal domain D H N S pro-domain catalytic domain C-terminal domain

Endoplasmic Reticulum Golgi Secretion

Lambert G et al. (2009) Atherosclerosis

PCSK9: the chaperone (binds to the LDLR)

EGFA domain

PCSK9 LDLR

CHRD Pro-domain Catalytic domain

Endocytosis

Seidah NG, et al. (2014) Circ Res

PCSK9-LDLR Binding Kd=750±80nM (at pH 7.5) Kd= 10±1nM (at pH 5.5)

PCSK9 targets the LDLR to the lysosome for degradation

LDLR Endosome Merge

+ PCSK9

Lambert G et al. (2016) Eur. Heart J. Surdo PL et al. (2011) EMBO Rep

LDLR Conformation Open (at pH 7.5) Closed (at pH 5.5) alone Open (at pH 5.5) bound to PCSK9

PCSK9 reduces LDLR cell surface expression dose dependently

MFI = median fluorescence intensity * p<0.05, ** p<0.01 vs. condition no PCSK9 (0)

Lambert G. et al. (2014) J Am Coll Cardiol Thedrez A. et al. (2016) Arterioscler Thromb Vasc Bio

PCSK9 in brief: a natural inhibitor of the LDL receptor

Lambert G et al. (2012) J Lipid Res

Statins coregulate the Expression of the LDLR and of PCSK9

SREBP2 PCSK9 LDL-C LDLR

Statins

20% FCS 0.5% FCS 0.5% FCS + Mevastatin 328 345 352 365

250 300 350 400 Atorva Atorva 10 10 (n= (n=449) 449) Atorva Atorva 20 20 (n= (n=449) 449) Atorva Atorva 40 40 (n= (n=447) 447) Atorva Atorva 80 80 (n= (n=399) 399) Mean n PCSK SK9 9 (ng/m /mL)

The development of PCSK9 inhibitors

mAb

Lambert G et al. (2012) J Lipid Res

Robinson JG et al. N Engl J Med 2015;372:1489-1499 Sabatine MS et al. N Engl J Med 2015;372:1500-1509

PCSK9 inhibition with mAbs in clinical trials reduces LDLC by 60% on top of standard therapy

Alirocumab Evolocumab

All patients Atorva 10 Atorva 20 Atorva 40 Atorva 80 10 20 30 40 50

Lipoprotein (a) levels (mg/dl) Non-diabetics Diabetics

* * # # #

p=0.005 p=0.03 p=0.70 p=0.10 p=0.003

PCSK9 inhibitors also reduce Lp(a)

PCSK9 LDL-C LDLR Lp(a) Statins Pcsk9 mAbs

=

• 60%
• 30%

Lp(a) hepatic clearance is not mediated by the LDLR

PRIMAR MARY HUMAN AN HEPATOCY OCYTES TES

+ PCSK9 (0 - 3.1 ug/mL) +/- alirocumab (8ug/mL) LDLR expression

• Fluo. LDL and Lp(a) uptake

PCSK9 increases the hepatic secretion of Lp(a)

IV

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N 3-40 40 1 unique peptide for apo(a) quantification by LC-MS/MS LFLEPTQ TQAD ADIALL ALLK = PeptQU

QUANT m/z 786.4512

Croyal et al. (2015) Arterioscler Thromb Vasc Biol Villard et al (2016) JACC Basic Transl Sci

Apo(a)

• PCSK9 is a natural circulating inhibitor of the LDLR. PCSK9 targets the

receptor for degradation following endocytosis.

• PCSK9 and LDLR genes are co-regulated by intracellular cholesterol

content and statin treatment (mainly expressed in the liver).

• Targeting plasma PCSK9 with mAbs lowers LDL-C as well as Lp(a) in

clinical trials both in monotherapy and on top of statins.

• We propose that PCSK9 does not significantly modulate Lp(a) catabolism

but rather enhances the hepatic secretion of Lp(a), and that anti-PCSK9 mAbs reduce Lp(a) levels primarily by altering this pathway.

CONCLUSION