Interim results from a dose escalating study of AMT-060 (AAV5-hFIX) gene transfer
in adult patients with severe hemophilia: Follow-up to 6 and 12 months
2314
F. Leebeek1, M. Tangelder2, K. Meijer3, G. Castaman4, F. Cattaneo5, M. Coppens6, P. Kampmann7, R. Klamroth8, R. Schutgens9, E. Seifried10, J. Schwaeble10, H. Boenig10, M. Hendriks2, W. Miesbach10, on behalf of the CT-AMT-060-01 Study Group
Erasmus Medical Center, Rotterdam, the Netherlands; 2uniQure biopharma, B.V., Amsterdam, the Netherlands; 3University Medical Center Groningen, Groningen, the Netherlands; 4Azienda Ospedaliera Universitaria Careggi, Florence, Italy; 5Chiesi Farmaceutici S.p.A., Parma, Italy;
6
Academic Medical Center, Amsterdam, the Netherlands; 7Rigshospitalet, Copenhagen, Denmark; 8Vivantes Klinikum, Berlin, Germany; 9University Medical Center, Utrecht, Netherlands; 10Universitätsklinikum Frankfurt, Frankfurt, Germany
■■ Hemophilia B is an X-linked genetic disorder characterized by a
bleeding tendency with risk of potentially life-threatening bleeds and
debilitating damage to joints and muscles1
■■ The development of gene transfer for hemophilia is advancing rapidly
and offers the potential to shift the disease phenotype from severe to
mild with a single treatment2
WHAT IS AMT-060?
■■ AMT-060 consists of an adeno-associated virus 5 (AAV5) vector
incorporating a codon-optimized wildtype human FIX (hFIX) gene
under control of the liver-specific promotor LP1 (Figure 1)
■■ The hFIX gene cassette has previously achieved clinically relevant
results in patients with hemophilia B:3-5
EFFICACY
■■ Endogenous FIX activity, measured at least 10 days after the most recent
administration of exogenous FIX
■■ Bleeding episodes as assessed by:
□□ Number and type of bleeds
□□ Annualized spontaneous bleeding rates, calculated based on
bleeds treated with exogenous FIX occurring after discontinuation of
prophylaxis post-AMT-060
■■ The proportion of patients remaining prophylaxis-free post AMT-060
■■ Total annualized exogenous FIX consumption
■■ Bleeding data and FIX consumption were collected:
□□ Retrospectively from patient diaries and hospital records for 1 year prior
to study entry
□□ Prospectively via e-diary during study, and reviewed by the physician at
study visits
□□ Marked reductions in bleeding episodes and prophylactic FIX use
SAFETY
■■ Treatment-emergent adverse events (TEAE)
■■ AAV5-specific T-cell response and antibodies
■■ FIX inhibitors
□□ No transgene-associated safety signals
Figure 2. Study design
□□ Stable and durable increases in FIX activity for ≥5 years
■■ The AAV5 capsid has the potential to be used in a broad patient
population due to low pre-existing immunity6
Figure 1. The structure of AMT-060
(maximum
6 weeks
prior to dosing)
Weeklyb
Cohort 2 (n=5a)c
AAV5-hFIX 2x1013 gc/kg
AAV5
capsid
Weekly
b
Biweekly
□□ Cohort 1: 5.2% (95% CI 2.5-7.9%, n=4) (Figure 3A)
□□ Cohort 2: 6.9% (95% CI 2.5-11.3%, n=5) (Figure 3B)
■■ FIX activity levels remained stable over the duration of follow up in
both cohorts
■■ 9/10 patients (both dose cohorts) improved their disease severity
(Table 2)
Biannually
Quarterly
Biannually
0
1
12
26
Weeks
3
Patient 2
Patient 1
Patient 4
Patient 5
15
10
5
Years
After the administration of AAV5-hFIX to each patient, the Data Monitoring Committee evaluated available safety data over 24-hours
before dosing of the next patient could be initiated. bProphylactic FIX replacement therapy was tapered between weeks 6-12 if FIX
activity was ≥2.0% at least two consecutive visits. Investigators could taper prophylaxis later than 12 weeks at their discretion. The
decision to continue tapering/withholding of prophylactic FIX replacement therapy was based individual assessment by the
investigator, but included the requirement to document that the subject was able to maintain a FIX activity level ≥2.0%. cCohort 2
dosing was initiated after the completion of Cohort 1 dosing and review of initial safety data by the Data Monitoring Committee
AIM
■■ Investigate the safety and efficacy of two doses of AMT-060 in adult
patients with severe or moderate-severe hemophilia B
MATERIALS AND METHODS
STUDY DESIGN
■■ Multi-national, multi-center, open-label, dose-escalating Phase 1/2 study in
patients with FIX activity ≤2% of normal and a severe bleeding phenotype
STUDY POPULATION
■■ Male patients ≥18 years with severe or moderate-severe (FIX ≤2%)
hemophilia who required either:
□□ Continuous exogenous FIX prophylaxis
□□ On-demand exogenous FIX AND either ≥4 bleeds per year or chronic
hemophilic arthropathy
■■ Exclusion criteria included:
□□ Pre-existing neutralizing AAV5 antibodies
□□ FIX inhibitors
□□ Active Hepatitis B (s and e antigens & HBV DNA) and/or Hepatitis C
(HCV RNA)
□□ Uncontrolled HIV (CD4+ ≤200/µL or viral load >200 genome copies (gc)/mL)
INTERVENTION
■■ Patients (n=10) were treated in two consecutive, escalating dose cohorts
(Figure 2)
□□ 5x1012 gc/kg (n=5; Cohort 1)
□□ 2x1013 gc/kg (n=5; Cohort 2)
■■ AMT-060 was administered via a single 250 mL intravenous infusion over
30 minutes
KEY OUTCOME MEASURES
■■ A data cutoff date of 15 October 2016 was used for all analyses, capturing
up to 52 weeks of follow up for Cohort 1 and up to 26 weeks for Cohort 2
RESULTS
DEMOGRAPHIC AND BASELINE CHARACTERISTICS
■■ Nine of 10 patients were classified as having severe (<1% FIX
activity) hemophilia; 1 patient in Cohort 1 had a moderate/severe
(1.5% FIX activity) phenotype
■■ Patients enrolled in Cohort 1 tended to be older, have more severe
arthropathy, and experienced more bleeds in the year prior to study
entry compared to Cohort 2, despite intensive prophylactic regimens
(Table 1)
Table 1. Demographics and baseline characteristics
Variable
Category
Cohort 1
(N=5)
60.2 (15.9)
69
35 – 72
Mean (SD)
Age (years)
Median
Min – Max
Black or African
0
Race
American
White
5 (100%)
Not Hispanic or
Ethnicity
5 (100%)
Latino
N
5
BMI (kg/m2)
Mean (SD)
25.5 (4.1)
Median
25.1
N
5
FIX prophylaxis
Mean
4800
(IU/week)
Min, Max
2000, 8000
Mean bleeds in the year
N
5
prior to enrollment
Total (Sp/T/Unk) 14.4 (9.8/2.8/1.8)
Hemophilia joint
Mean
24.4
health scores
Min, max
2, 49
HIV positive status
n/N
1/5
Prior hepatitis C infection
n/N
4/5
Cohort 2
(N=5)
38.2 (5.9)
35
33 – 46
Unknown
AMT-060 administration
and prophylaxis tapering period
1
16
4
8
12
16
20
24
28
32
36
40
44
48
52
56
Weeks after AMT-060 infusion
Table 4. Treatment-emergent adverse events classified as possibly/
probably related to treatment
TEAE
Any related TEAEs
Liver enzyme increased
Pyrexia
Anxiety
Drug ineffective
Palpitations
Headache
Prostatitis
Rash
4
12
2
10
1
2
8
6
2
1
5
4
3
4
8
12
5
8
7
4
2
1
10-12
7-9
4-6
1-3
1-3
4-6
7-9
0
Before AMT-060 administration
Patient 6
Patient 7
Patient 8
Patient 9
1
10-12a
□□ Clinically relevant FIX activity ≥3% sufficient to shift the clinical
phenotype was established in all 5/5 patients
After discontinuation of prophylaxis
□□ 4/4 patients dependent on continuous prophylaxis at study entry
have discontinued their prophylaxis regimens
n=4; Patient 3 remaining on prophylaxis excluded. aFollow-up duration for individual patients in the Months 10-12 bin ranged
from 1-3 months.
Patient 10
□□ Spontaneous bleeds were markedly reduced
COHORT 2
15
□□ Mild, asymptomatic increases in liver enzymes occurred in
2/5 patients, were not associated with a capsid-specific T-cell
response and resolved with no loss of FIX activity
■■ Following discontinuation of prophylaxis in 4/4 patients in Cohort
2, a single mild spontaneous bleed has been reported over 8-31
weeks of follow-up
10
■■ Follow up of patients in Cohort 1 demonstrates elevations in FIX
activity are stable and durable up to 52 weeks following AMT060 administration
■■ Patient 8 with on-demand FIX replacement at study entry and postAMT-060 reported no spontaneous bleeds during 26 weeks post
AMT-060, compared to 3 in the year prior
5
0
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
Weeks after AMT-060 infusion
Only values at least 10 days after last FIX administration are included. Patient 3 remained on prophylaxis and therefore is not
` included; *Patient 5 had a FIX activity of 3.1% at his 52-week visit, which occurred after the data cutoff date
Table 2. Mean steady state FIX levels and prophylaxis status
by patient
ADVERSE EVENTS
■■ There were no discontinuations due to adverse events or deaths
■■ 73 TEAEs occurred in 9 patients
1 (20%)
1
6.3 (5.9-6.7)
52
Mild
No
4 (80%)
2
4.7 (4.5-5.0)
52
Moderate
No
3
<2
52
Moderate-severe
Yes
4
6.8 (6.3-7.3)
52
Mild
No
5
3.0 (2.5-3.5)
39
Moderate
No
□□ 1 patient: short, self-limiting fever in first 24 hours post-AMT-060
6
12.7 (11.9-13.5)
26
Mild
No
7
6.4 (6.0-6.7)
26
Mild
No
□□ 2 patients: mild, asymptomatic elevations in liver enzymes (see
below)
8
6.8 (5.8-7.7)
26
Mild
N/Ab
9
3.0 (2.7-3.3)
24
Moderate
No
10
5.7 (5.3-6.1)
22
Mild
No
BLEEDING EPISODES AND PROPHYLAXIS USE
■■ No severe bleedings were reported after AMT-060 administration
Presented at the American Society of Hematology, December 3-6, 2016
■■ The observed safety profile and indicators of clinical efficacy
support selection of the 2x1013 gc/kg dose for pivotal trials
SAFETY
Prophylaxisa
(Yes/No)
Only values at least 10 days after last FIX administration are included; Prophylaxis status is as of last visit;
b
Used on-demand FIX replacement prior to study entry
□□ Reductions in bleeding frequency over time suggest improved
clinical benefit over prophylactic replacement with exogenous FIX
■■ Annualized spontaneous bleed rate was reduced from 3.0 to 0.7
(76%; n=4; 1 patient missing historical bleed data)
Hemophilia
Phenotype post
AMT-060
a
n - (%) - E
Cohort 2 (N=5)
3 - (60.0%) - 10
2 - (40.0%) - 3a
2 - (40.0%) - 2
1 - (20.0%) - 1
N/A
1 - (20.0%) - 1
1 - (20.0%) – 1
1 - (20.0%) – 1
1 - (20.0%) - 1
■■ In patients receiving 2x1013 gc/kg of AMT-060:
Months
B) Cohort 2
20
n - (%) - E
Cohort 1 (N=5)
3 - (60.0%) - 4
1 - (20.0%) - 1
1 - (20.0%) - 1
1 - (20.0%) - 1
1 - (20.0%) - 1
N/A
N/A
N/A
N/A
■■ In this ongoing dose-escalation Phase I/II trial, a single infusion
of AMT-060 at both doses tested (5x1012 and 2x1013 gc/kg) was
generally safe and well-tolerated with no development of
inhibitors
Duration of
Follow Up
(Weeks)
Highlight indicates a characteristic that differs notably between cohorts; a1 patient received on-demand treatment and
is therefore not included; b1 patient missing historical bleed data; n, number of patients with the characteristic; N, total
number of patients in the cohort; HIV, human immunodeficiency virus; Sp, spontaneous; T, traumatic; Unk, unknown
■■ No patients demonstrated sustained AAV5 capsid-specific T-cell activation
SUMMARY AND CONCLUSIONS
Mean % FIX
activity (95% CI)
5
26.6 (3.0)
27.2
4a
5625
4000, 10500
4b
4 (3/1/0)
6.8
0, 17
0/5
2/5
■■ No patients developed inhibitors to FIX
14
Patient
5 (100%) ■■ As expected, all patients developed antibodies to AAV5
N, number of patients in cohort; n, Number of patients with events; N/A, not applicable; (%), Percentage of patients
with events; E, Number of events; TEAE, Treatment emergent adverse event; a2 events reported in the same patient
2
0
Endogenous activity (%)
LP-1
(Liver-specific promoter)
18
0
5
Traumatic
Spontaneous
a
Human wild type FIX
(codon optimized)
Figure 4. Total number of bleeds experienced by patients in Cohort 1
by quarter before and after AMT-060
*
Prophylactic FIX tapering
-6
■■ Patient 3 who remained on prophylaxis (per protocol requirement;
FIX <2%) reduced bleeds by 45% (22 total bleeds in the year prior to
AMT-060 vs 12 post AMT-060)
■■ Annualized spontaneous bleed rate was reduced from 8.3 to 3.4
(59%; n=4; 1 patient remaining on prophylaxis excluded), with no
spontaneous bleeds reported over the last 14 weeks of observation
□□ 4/5 patients in Cohort 2 achieved FIX activity values consistent
with a mild phenotype (>5% to 40% activity)2
b
Expression
cassette
□□ Annualized FIX consumption was reduced by 85% in these 4
patients after AMT-060 (cumulative total 1,562,000 IU prior to AMT060 vs. 232,808 after; n=4)
A) Cohort 1
Quarterly
Biweekly
■■ Number of bleeds decreased over time following discontinuation
of prophylaxis in 4/5 patients, all 4 of whose bleeding pattern was
poorly responsive to prophylaxis at study entry (Figure 4)
Figure 3. Consistent, stable FIX activity over time
Follow up
Cohort 1 (n=5a)
AAV5-hFIX 5x1012 gc/kg
IMMUNOGENICITY
COHORT 1
■■ The mean of all endogenous FIX activity values after cessation of
prophylaxis was:
20
AMT-060
Administration
Screening
ENDOGENOUS FIX ACTIVITY AND PHENOTYPIC
SEVERITY
Number of bleeding episodes
INTRODUCTION
Endogenous activity (%)
1
■■ The majority of TEAEs were considered mild in nature, and none
were considered severe
■■ TEAEs considered possibly/probably related to treatment are shown
in Table 4
■■ 3 serious adverse events (SAE) classified as possibly related
occurred:
■■ 3 patients experienced mild, asymptomatic elevations in liver
enzymes not associated with changes in FIX activity or a capsidspecific T-cell response
□□ 1 patient in Cohort 1, received tapering course of prednisolone;
resolved (classified as an SAE)
□□ 2 patients in Cohort 2, received tapering courses of prednisolone;
resolved (1 event classified as an SAE)
REFERENCES
Srivastava A, et al. Haemophilia. 2013;19:e1-47; 2White GC 2nd. Thromb Haemost 2001;85:560;
3
Nathwani AC, et al. N Engl J Med 2011;365;2357–2365; 4Nathwani AC, et al. N Engl J Med
2014;371:1994-2004; 5Nathwani AC, et al. Oral presentation at European Society of Gene and
Cell Therapy (ESGCT), 18-21 October 2016, Florence, Italy; 6Boutin S, et al. Human Gen Ther
2010;21:704-12.
1
ACKNOWLEDGEMENTS
We thank the participating patients and their families. We would also like to thank the following
individuals for their assistance with the conduct of the study:
L. Landman, M. van Maarseveen, K. Nooij, M. Kemper, C. Ris-Stalpers (Academic Medical Center
Amsterdam); M. Kruip, A. Beishuizen, G. Mulders, E. van der Graaf, R. Van Lommel, R. Bouamar,
C. Bakker (Erasmus Medical Center); F. Peyvandi (Fondazione IRCCS Cà Granda Ospedale
Maggiore Milan); E. Funding, R. Duus Müller, R. Svensgaard, C. Nielsen, Mette Nordahl Rahbek.
(Rigshospitalet Copenhagen); S. Gundermann, K. Scholz (University Hospital Frankfurt am Main); F.
Yspeerd, K. Thedinga, M. Voskuilen, B. Molmans, M. Segers, B. Waarts (University Medical Center
Groningen); P. van der Valk, E. Beers, D. Dekker, M. van Haaften-Spoor, S. Oortwijn-De Loo, A.
Braem-Enneman, M. Timmer, H. Aanstoot (University Medical Center Utrecht); C. Kubicek-Hofmann,
A. Orlovic, Y. Limberg (Vivantes Klinikum Berlin)
DISCLOSURES
F. Leebeek, K. Meijer, G. Castaman, M. Coppens, P. Kampmann, R. Klamroth, R. Schutgens,
J. Schwaeble, H. Boenig, W. Miesbach are study investigators and have received consultant fees
from uniQure B.V. E. Seifried is a study investigator. M. Tangelder and M. Hendriks are uniQure
employees. F. Cattaneo is a Chiesi Farmaceutici S.p.A employee. Writing support, funded by uniQure
B.V., was provided by Mike Lappin of GK Pharmacomm Ltd.