1) The document discusses a Phase 3 clinical trial investigating the effects of the ASK1 inhibitor selonsertib (SEL) in patients with diabetic kidney disease (DKD). 2) The trial did not meet its primary endpoint of a 50% improvement in eGFR from baseline to week 48. However, exploratory analyses found SEL induced acute but reversible eGFR declines followed by stabilization or improvement in eGFR slope over time. 3) Adverse events including acute kidney injury and fluid overload were similar between SEL and placebo groups. The study was limited by its short duration and data issues from two sites.

1. ASK1 INHIBITION IN DKD
Christos Argyropoulos MD, PhD, FASN
University of New Mexico School of Medicine

2. Disclosures Site coinvestigator for the Phase 3 study of SEL
MOSAIC (GS-US-223-1017)

3. Public Service Announcement

4. Overview – Learning
Objectives
Epidemiology and Current Standard of Care for
Diabetic Kidney Disease (DKD)
Apoptosis signal-regulating kinase 1 (ASK1) in DKD
Selonsertib (SEL): an ASK1 inhibitor in human DKD
Tubular handling of creatinine and transporters in drug
development

5. Epidemiology and
Current Standard of
Care in DKD

6. ESRD incidence is increasing because of DM
Adjusted prevalence of ESRD in the US 1996-2014 .. but certain states have it worse than others
2016 Annual Data Report, Vol 2, ESRD, Ch 1 Fig 1.16
BMC Nephrol. 2018 Feb 27;19(1):47. doi:
10.1186/s12882-018-0842-4.

7. JAMA. 2016;316(6):602-610
Incidence of DKD ↑, while care improves

8. Diabetic CKD + Cardiovascular Disease =
Hospitalization + Death
Data source: Medicare 5 percent sample. January 1, 2014 point prevalent patients aged 66 and
older. Adj: age/sex/race. Ref: all patients, 2014. Abbreviations: CKD, chronic kidney disease;
CVD, cardiovascular disease; DM, diabetes mellitus.
Death Hospitalization
2016 Annual Data Report, Vol 1, CKD, Ch 3

9. … and a substantial % of DKD is
now non-proteinuric
Diabetes Metab. 2012 Oct;38(4):291-7 JAMA. 2016;316(6):602-610
NHANES prevalence of non-proteinuric DKD : ~48%

10. http://www.nephjc.com/news/credence

11. Glucose-lowering medication in DM2: 2019 version
American Diabetes Association Diabetes Care 2019;42:S90-S102

12. Diabetes and
Kidney Disease
2019: August
Special Section
https://www.kidneynews.org/kidney
-news/current-issue/diabetes-and-
kidney-disease-2019-august-
special-section

13. Landscape
of SGLT2i
trials in the
CKD staging
system

14. Cardiovascular
and Renal
Outcomes of
SGLT2i
https://www.kidneynews.org/kidney
-news/findings/sodium-glucose-co-
transporter-2-inhibitors

15. Managing DKD in 2019
1. Initiate and sustain evidence- based pharmacological therapy
ACEi/ARB / ? Aldo antagonists
2. Treat the complications that arise as a result of therapy or DKD
Hyperkalemia (diuretics/patiromer)
Volume overload
CKD complications
3. Consult referring physicians about renal safety/efficacy/dosing of
anti-glycemic therapies
Metformin/SGLT2i/GLP-1RA/DPP-4i

16. Pathogenesis
of DKD
THE ROLE OF THE ASK-1

17. Glomerular Hyperfiltration initiates DKD
Normal state Diabetes
Clin J Am Soc Nephrol 12: 2032–2045, 2017 Am J Kidney Dis. 71(6):884-895,2018

18. From Hyperfiltration to Molecular
Pathways in DKD
Clin J Am Soc Nephrol 12: 2032–2045, 2017 Am J Kidney Dis. 71(6):884-895,2018
.
Am J Physiol. 1985 Sep;249(3 Pt 2):F324-37

19. Sensing and
transducing badness
1. Therapeutic inhibition of p38 or JNK can reduce
inflammation and fibrosis of animal models of kidney
disease (discussed in next slide)
2. Ubiquitous functions of p38/JNK:
 P38 MAPK inhibition : liver toxicity
 JNK inhibition: exacerbation of albuminuria
3. ASK1/MAP3K5 is predominantly activated in
pathologic states:
Can we inhibit ASK1 and avoid the treatment emergent side
effects of modulation of this pathway?
Am J Physiol Renal Physiol 311: F373–F381, 2016
ASK1: Apoptosis Signal Regulated Kinase 1
MAP3K5: Mitogen-activated protein kinase kinase kinase 5

20. Kinases and the Kidney
P38 MAPK
Activation protects cells from hyperosmotic
stress
Activated in proliferative GN
IgA
Postinfectious
SLE
Not activated in nonproliferative GN (MCD,
membranous, FGSS)
Activated in DKD
Activation noted in all intrinsic renal cell types
but also infiltrating cells (myofibroblasts)
JNK
Activation protects cells from
hyperosmotic stress
Therapeutic inhibition protects from
worsening renal function in
antiGBM disease
Ischemia reperfusion injury
Ureteric obstruction model
In DKD JNK blockade reduces
inflammation but increases proteinuria
Am J Physiol Renal Physiol 311: F373–F381, 2016

21. Postulated Role of ASK-1
in diabetic nephropathy
Genetic animal data suggest that upstream
deletion of MKK3 may protect from various
forms of kidney disease
ASK1 appears to transduce oxidase stress by
dissociating from its chaperon thioredoxin (TRX)
TRX levels are regulated by TRX-interacting
protein (TXNIP)
Levels increase in DKD and correlate with fibrosis
Oxidative stress in DKD can arise from
intracellular stress, or come about as a result of
ANGII membrane signaling
Am J Physiol Renal Physiol 311: F373–F381, 2016

22. ASK1 inhibition in Nos3 KO diabetic
mice
ASK1 inhibition
reduced
glomerulosclerosis
reduced inflammation
Improved renal
function
Had minimal effect on
established proteinuria
Diabetes 2015 Nov; 64(11): 3903-3913

23. ASK1 pathway in human DKD and db/db eNOS KO mice
J Clin Invest. 2018;128(10):4485-4500

24. ASK1 inhibition in
human DKD

25. JASN 30: 1980–1990, 2019

26. Ins and Outs
INCLUSION CRITERIA
Prior diagnosis of DKD
Male or female between 30 and 75 years
of age, inclusive
Type 2 DM ≥6 months
eGFR and UACR at screening within
protocol-defined criteria by disease stage
(Stage 3a w UACR > 600 to Stage 4 w
UACR < 150
Stable maximum tolerated RAASi
EXCLUSION CRITERIA
T1DM
A1c > 9.5%
Known non diabetic kidney disease
UACR > 5000 mg/g
ESRD
Dual RAASi
Pregnancy
JASN 30: 1980–1990, 2019

27. Study Design and Outcomes
RANDOMIZATION
1:1:1:1 to the three doses of SEL or
Placebo
Randomization stratified by eGFR strata
and UACR
Duration of study 48 weeks
OUTCOMES AND STATISTICAL
METHODS
50% improvement in eGFR from baseline to
week 48
Study was powered for this endpoint for a
sample size of 75 patients per group
Sequential testing procedure for the highest
to the lowest dose of PBO
Mixed model analysis for repeated
measures
Plan modified to include a two slope model
when an acute increase in SCr was detected
JASN 30: 1980–1990, 2019

28. JASN 30: 1980–1990, 2019

29. Characteristic Placebo (n=85) Selonsertib 2 mg (n=81) Selonsertib 6 mg (n=84) Selonsertib 18 mg (n=83) Total (N=333)
Mean age (SD), yr 62 (7.9) 63 (8.1) 62 (8.1) 63 (9.0) 63 (8.3)
Men, n (%) 53 (62.4) 53 (65.4) 64 (76.2) 56 (67.5) 226 (67.9)
Race, n (%)
Asian 3 (3.5) 3 (3.7) 4 (4.8) 2 (2.4) 12 (3.6)
Black 19 (22.4) 20 (24.7) 23 (27.4) 11 (13.3) 73 (21.9)
White 61 (71.8) 53 (65.4) 57 (67.9) 68 (81.9) 239 (71.8)
Other 2 (2.4) 5 (6.1) 0 2 (2.4) 9 (2.7)
Hispanic or Latino ethnicity, n (%) 30 (35.3) 25 (30.9) 31 (36.9) 33 (39.8) 119 (35.7)
Mean body mass index (SD), kg/m2 34.7 (6.78) 34.6 (8.19)a 35.6 (8.54)b 35.4 (8.06) 35.1 (7.89)c
Prior medications of interest, n (%)
ACEi 31 (36.5) 33 (40.7) 31 (36.9) 34 (41.0) 129 (38.7)
ARB 44 (51.8) 36 (44.4) 42 (50.0) 39 (47.0) 161 (48.3)
Medical history
Mean serum creatinine (SD), mg/dl 2.3 (0.73) 2.3 (0.72) 2.3 (0.74) 2.2 (0.68) 2.3 (0.71)
Mean eGFR (SD), ml/min per 1.73 m2 31.4 (11.87) 31.6 (10.92) 31.9 (11.58) 31.1 (10.44) 31.5 (11.18)
Diabetes, n (%) 68 (80.0) 64 (79.0) 74 (88.1) 67 (80.7) 273 (82.0)
Diabetes: neuropathy 43 (50.6) 35 (43.2) 47 (56.0) 42 (50.6) 167 (50.2)
Diabetes: retinopathy 27 (31.8) 30 (37.0) 30 (35.7) 24 (28.9) 111 (33.3)
Diabetes: gastroparesis 0 2 (2.5) 2 (2.4) 0 4 (1.2)
Congestive heart failure, n (%)d 12 (14.1) 12 (14.8) 8 (9.5) 14 (16.9) 46 (13.8)
Coronary artery bypass graft, n (%)e 6 (7.1) 8 (9.9) 6 (7.1) 13 (15.7) 33 (9.9)
Coronary artery disease, n (%) 24 (28.2) 27 (33.3) 20 (23.8) 34 (41.0) 105 (31.5)
Dyslipidemia, n (%) 68 (80.0) 60 (74.1) 64 (76.2) 66 (79.5) 258 (77.5)
JASN 30: 1980–1990, 2019

30. Primary Efficacy Analysis
JASN 30: 1980–1990, 2019

31. SEL induces a dose and exposure
dependent change in eGFR
JASN 30: 1980–1990, 2019

32. Exploratory analysis
JASN 30: 1980–1990, 2019

33. Exploratory Analysis – Cystatin C
JASN 30: 1980–1990, 2019

34. Effects on
proteinuria & KIM-1
JASN 30: 1980–1990, 2019

35. Pharmacodynamic – Pharmacokinetic correlations:
phosphor p38 (a marker of ASK1 inhibition declined with
therapy and correlated with chronic eGFR slope)
JASN 30: 1980–1990, 2019

36. Adverse events of grade 3 or greater
Adverse Event Placebo
(n=85)
Selonsertib 2 mg
(n=81)
Selonsertib 6 mg
(n=84)
Selonsertib 18 mg
(n=83)
Any AE of grade 3 or greater severity, n (%) 15 (17.6) 21 (25.9) 20 (23.8) 21 (25.3)
AKI 2 (2.4) 1 (1.2) 3 (3.6) 1 (1.2)
Cardiac failure, congestive 2 (2.4) 1 (1.2) 1 (1.2) 3 (3.6)
Cellulitis 1 (1.2) 1 (1.2) 2 (2.4) 2 (2.4)
Pneumonia 0 1 (1.2) 1 (1.2) 2 (2.4)
Dyspnea 1 (1.2) 0 2 (2.4) 1 (1.2)
ESRD 2 (2.4) 0 2 (2.4) 0
Acute myocardial infarction 0 1 (1.2) 2 (2.4) 0
Hyperkalemia 0 0 1 (1.2) 2 (2.4)
Hypertension 1 (1.2) 2 (2.5) 0 0
Chronic obstructive pulmonary disease 0 2 (2.5) 0 0
Renal failure 0 2 (2.5) 0 0
CKD 2 (2.4) 0 0 0
JASN 30: 1980–1990, 2019

37. Adverse events
Three AEs of special interest: ARF/Cardiac Failure/Fluid
overload
ARF more common in SEL (10.7%-16%) vs PBO (8.2%)
Higher rate of grade 3 creatinine elevations in the PBO
Occurrences of CHF/volume overload same in both groups
AEs leading to study drug discontinuation : SEL (12.1%) vs
9.4% (PBO)
No change in body weight, blood pressure, A1C
JASN 30: 1980–1990, 2019

38. Take-home messages
EFFICACY - SAFETY
SEL did not meet primary end point
Differences in eGFR confounded by acute changes:
 10% from baseline @ week 4
Acute effect unanticipated by the transporter studies
required by the FDA in the 2012 document
Acute effect similar in magnitude but not mechanism to
RAASi
Chronic slope analyses suggests a potentially beneficial
effect
No effect on proteinuria
No signals on CHF/volume overload (e.g. bardoxolone)
LIMITATIONS
Post-hoc analyses *after* the acute creatinine
effect was recognized
Two sites with GCP violations and unreliable
data (n=20 patients)
Too short a follow up to show an effect on
slope

39. JASN 30: 1980–1990, 2019

40. Whole body kinetics of creatinine
𝐶𝐿 𝐶𝑟 = 𝐶𝐿 𝑓𝑖𝑙𝑡𝑟𝑎𝑡𝑖𝑜𝑛 + 𝐶𝐿 𝑠𝑒𝑐𝑟𝑒𝑡𝑖𝑜𝑛 − 𝐶𝐿 𝑟𝑒𝑎𝑏𝑠𝑜𝑟𝑝𝑡𝑖𝑜𝑛
𝐶𝐿 𝐶𝑟 = (1 − 𝐹𝑅) ∙ 𝑓𝑢 ∙ 𝐺𝐹𝑅 +
𝑅𝐵𝐹 ∙ 𝑓𝑢 ∙ 𝐶𝐿 𝑅,𝑖𝑛𝑡
𝑅𝐵𝐹 + 𝑓𝑢 ∙ 𝐶𝐿 𝑅,𝑖𝑛𝑡
Annu. Rev. Pharmacol. Toxicol. 2005. 45:689–723 Drug Metab Dispos 44:1498–1509, September 2016
“Michaellis – Menten “ like saturable
process

41. Tubular Handling of Creatinine
Drug Metab Dispos 44:1498–1509, September 2016

42. Cutoff that predicts Creatinine Elevation (and transporter mediated DDI) Cmax/I50 > 0.1
(OCT), >0.02 MATEs
Drug Metab Dispos 44:1498–1509, September 2016

43. SEL IN DKD : Ph3
EFFICACY AND SAFETY OF SELONSERTIB IN
PARTICIPANTS WITH MODERATE TO ADVANCED DIABETIC
KIDNEY DISEASE (MOSAIC)

44. Primary Endpoints
1.Clinical endpoint:Time from randomization to the firstoccurrence of any of the following
adjudicated events:
Confirmed ≥40% decline in eGFR from baseline, or
Kidney failure
◦ •Dialysis for at least 90 days,
◦ •Kidney transplantation, or
◦ •Confirmed decrease in eGFR to <15mL/min/1.73 m2for subjects without dialysis or kidney
transplantation), or
Death due to kidney disease
2.eGFR slope
https://clinicaltrials.gov/ct2/show/NCT04026165

45. Secondary End Points
Time from randomization to adjudicated:
•Cardiovascular (CV) death or hospitalization for heart failure
•First occurrence of an event in the CV composite endpoint (includes CV death, non-fatal
MI, non-fatal stroke, or hospitalization for heart failure)
•CV death
•Atrial fibrillation
•CV death or kidney failure
•All-cause death (death occurring during the study from any cause) or kidney failure

46. Exploratory End Points
•Health-related quality of life, work productivity, and activity impairment
•Functional status: 6-minute walk test (6MWT) and sit-to-stand (STS)
•Healthcare resource utilization
•Albuminuria
•Association between urine and blood biomarkers with clinical outcomes
•PK characteristics for SEL and its metabolite (GS-607509)

47. Population
INCLUSION CRITERIA
Diagnosis of type 2 diabetes mellitus (T2DM) as per local guidelines.
eGFR and urine albumin to creatinine ratio (UACR) must one of
◦ a: eGFR (mL/min/1.73 m^2): ≥ 45 to < 60; UACR (mg/g): ≥ 600
◦ b: eGFR (mL/min/1.73 m^2): ≥ 30 to < 45; UACR (mg/g): ≥ 300
◦ c: eGFR (mL/min/1.73 m^2): ≥ 20 to < 30; UACR (mg/g): ≥ 150
Treatment with maximally tolerated doses of either an angiotensin
converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB)
or documented intolerance
Individuals already receiving sodium-glucose co-transporter-2 (SGLT-2)
inhibitors must be on a stable dose for at least 2 weeks prior to
enrollment
Mean systolic blood pressure (SBP) must be <160 mmHg and mean
diastolic blood pressure (DBP) must be <100 mmHg
EXCLUSION CRITERIA
HbA1c > 12.0% within 30 days prior to enrollment
If < 30 years of age, any history of chronic insulin therapy or diabetic ketoacidosis
Body mass index (BMI) > 50 kg/m^2
UACR > 5000 mg/g on any measurement during screening
End stage renal disease (ESRD) (i.e., peritoneal dialysis, hemodialysis, or history of kidney
transplantation)
Anticipated progression to ESRD (need for dialysis or receipt of kidney transplant) within 3 months
after enrollment
Unstable CV disease
Pregnant or lactating females or planning to become pregnant or breastfeed during the study
Concurrent use of a mineralocorticoid receptor antagonist (MRA) or direct renin inhibitor (DRI) in
combination with an ACEi or ARB for at least 2 weeks prior to enrollment
Prior or ongoing clinically significant illness, medical condition, surgical history, physical finding, ECG
finding, or laboratory abnormality that, in the investigator's opinion, could adversely affect the safety of
the individual or impair the assessment of study results

48. Study schema
Run-in phase ALL subjects will receive both
placebo and SEL in order to establish two separate
baseline eGFRs
•All subjects need to receive placebo, because
some will be eventually randomized to placebo.
Need to establish a baseline eGFRwhile they are on
placebo.
•To account for acute artefactual effect of SEL on
eGFR, will establish a separate baseline eGFRfor
subjects who will be randomized to SEL.

49. Other information
136 global locations
Event Driven trial : anticipated 3,300 study participants
Study Duration 7/19/2019 – 12/2024
Median patient treatment duration 20 months
Study ID numbers
NCT04026165
GS-US-223-1017
2018-003951-39 ( EudraCT Number )
JapicCTI-194911

50. UNM Study Team
Allen Adolphe (PI – Division of General Internal Medicine)
Christos Argyropoulos (co-PI )
Greg Trejo (Regulatory/Research coordination – Nephrology/Clinical Trial Unit)