Raising the Bar for Hemophilia Management

Raising the Bar for Hemophilia Management
Guy Young, MD
Director, Hemostasis and Thrombosis Center
Children’s Hospital Los Angeles
Professor of Pediatrics
University of Southern California Keck School of Medicine
Robert F. Sidonio, Jr., MD, MSc
Professor of Pediatrics
Medical Director
Hemophilia of Georgia Center for Bleeding and Clotting Disorders
Children’s Healthcare of Atlanta

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COMMERCIAL SUPPORT
This activity is supported by an independent medical education grant from Sanofi.

Disclosures
Guy Young, MD
Consultant: Alnylam, ASC Therapeutics, Bayer, BioMarin, CSL Behring,
Genentech/Roche, HEMA Biologics, Novo Nordisk, Octapharma, Pfizer,
Sanofi, Spark, Takeda
Grants/research support: HEMA Biologics, Sanofi
Robert F. Sidonio, Jr., MD, MSc
Advisory board or panel: Bayer, HEMA Biologics/LFB, Hemab, Novo
Nordisk, Octapharma, Pfizer, Sanofi/Sobi, Star, Takeda
Consultant: Bayer, HEMA Biologics/LFB, Hemab, Novo Nordisk,
Octapharma, Pfizer, Sanofi/Sobi, Star, Takeda
Grants/research support: HEMA Biologics/LFB, Octapharma, Takeda
i3 Health has mitigated all relevant financial relationships

Learning Objectives
Define appropriate treatment goals and targets for the
management of hemophilia A and B
Evaluate the clinical utility of novel and emerging prophylactic
agents for the treatment of individual patients with hemophilia A
and B
Assess methods to improve the early detection of hemophilic
arthropathy development and progression
Apply strategies to enable increased physical activity for patients
with hemophilia while minimizing risk of bleeds

Patient Case: Hemophilia A
14-year-old male with severe hemophilia A with
history of transient inhibitor
Baseline FVIII <1%
Initially started on SHL FVIII
Trial of emicizumab for 12 months; developed a large
muscle bleed but wants to know his options
VIII = factor VIII; SHL = standard half-life.

Polling Question
What is known about muscle bleeds in patients on emicizumab?
a. Emicizumab does not prevent muscle bleeds
b. Emicizumab is only effective against joint bleeds
c. There are reports of serious muscle bleeds especially in teenagers
and young adults on emicizumab
d. Factor concentrates are proven to be more effective against muscle
bleeds than emicizumab

Patient Case: Hemophilia B
FIX = factor VIX; rFIX:Fc = recombinant factor IX Fc fusion protein; ABR = annualized bleeding rate.
19-year-old male with severe hemophilia B without
history of inhibitor
Baseline FIX <1%
Initially started on SHL FIX product 3 times a week
Recently attempted rFIX:Fc weekly with good trough at
Day 7 (2%) and ABR ~3
Active in soccer (promises doesn’t head the soccer ball)
Wants to consider alternative therapy as he is getting
“tired” of frequent injections

Polling Question
TFPI = tissue factor pathway inhibitor; EHL = extended half-life; siRNA = small interfering ribonucleic acid.
What are the novel options for prophylaxis for a young adult with
severe hemophilia B?
a. Factor replacement (SHL and EHL products) are the only option
b. An anti-TFPI subcutaneous drug such as concizumab or
marstacimab
c. An siRNA subcutaneous option such as fitusiran monthly or every
2 months
d. Options b and c are reasonable for prophylaxis

Hemophilia A and B: Scope of
the Problem and Unmet Needs

1950 1960 1970 1980 1990 2000 2010 2020 2030
Factor Replacement
Plasma Cryo pdFVIII/FIX rFVIII/FIX EHL Non-Factor Tx
Gene Tx
The History (and Future) of Hemophilia Treatment
Cryo = cryoprecipitate; pdFVIII/FIX = purified factor VIII/factor IX (FIX); rFVIII/FIX = recombinant FVIII/FIX; Tx = treatment.
Ozelo & Yamaguti-Hayakawa, 2022.

Why Do We Need New Therapies
for Hemophilia?

Hemarthrosis
Images courtesy of Guy Young, MD.
The most common long-lasting sequelae of hemophilia is
permanent joint disease called hemophilic arthropathy
Acute hemarthrosis

Synovitis

Arthropathy
How effective is prophylaxis at preventing hemophilic arthropathy?
End-stage arthropathy

Raising the Bar for Hemophilia Management

Longitudinal Comparison: Early and Delayed Prophylaxis
CPJAS = Colorado Pediatric Joint Assessment Scale; JOS = joint outcomes study; JOS-C = joint outcome study continuation.
Figure adapted from Boulden Warren et al, 2020.

~33%
up to 60%
Joint Bleeds Still Common, Even Among Patients on Prophylaxis
Wilkins et al, 2022; Srivastava et al, 2020.
of adult patients experienced breakthrough
joint bleeds despite prophylaxis treatment
of pediatric patients experienced breakthrough
joint bleeds despite prophylaxis treatment
Breakthrough joint bleeds can have detrimental effects on joint health
In a United Kingdom observational study over 1 year:

Joint Bleeds Can Cause Damage Via Multiple Pathways
Kizilocak & Young, 2019; Calcaterra et al, 2020.
A vicious circle of bleeding can occur—leading to permanent joint damage
1
Iron released into synovial fluid
causes chemical damage via
inflammatory cytokines and
chemokines
2
Synovium inflammatory damage
and degenerative cartilage
changes occur
3
New friable vessels, which are
more prone to bleeding, form via
neovascularization
Bleeding
Synovial inflammatory
damage/
degenerative cartilage changes
New friable vessels
via
neovascularization
Iron accumulation

FVIII Prophylaxis Delays Hemophilic Arthropathy
Manco-Johnson et al, 2007; Srivastava et al, 2020.
People with hemophilia A who
receive FVIII prophylaxis show
fewer imaging markers of joint
damage
Patients with severe FVIII
deficiency initiated on early FVIII
prophylaxis have better long-
term outcomes than those who
started later
Initiation of prophylaxis is
recommended in early childhood,
ideally before 3 years of age
Markers of joint health in a cohort of children
receiving FVIII prophylaxis or on-demand treatment
0
10
20
30
40
50
0
5
10
15
20
2/27
13/29
1/28
5/27
P=0.002
Patients
with
joint
damage
(%)
Patients
with
joint
damage
(%)
MRI Radiography
P=0.10
Prophylaxis On-
demand
Prophylaxis On-
demand

Regular FVIII Infusions Protect Bone and Joint Health
HJHS = Hemophilia Join Health Score.
Gamal Andrawes et al, 2020.
People with hemophilia A who
receive FVIII prophylaxis show
better HJHS and bone status
FVIII prophylaxis is associated
with improved bone and joint
status compared with on-
demand treatment
In hemophilia A, clinical
assessment of joint structure
and function is commonly
performed using the HJHS in
children and adolescents
0
20
40
60
80
100
0
1
2
3
4
5
6
7
8
P=0.022 P=0.035
23/35
5/15
HJHS and bone status in children with severe
hemophilia A who received low-dose FVIII prophylaxis
(n=35) or on-demand (n=15) treatment
Median
HJHS
Patients
(%)
Patients without bone
deformity
HJHS
Prophylaxis On-
demand
Prophylaxis On-
demand

Musculoskeletal Ultrasound (MSKUS)
Foppen et al, 2018; Bakeer & Shapiro, 2019.
Can Be Used to Assess Joint Health and Identify Source of Pain
MSKUS can be used to determine whether acute musculoskeletal pain is due to arthritis or is bleed-related
MSKUS is an accurate and available alternative to MRI
Benefits vs conventional MRI:
• Ultrasound can accurately assess synovial hypertrophy,
bone surface irregularities and cartilage abnormalities in
hemophilia patients with limited joint disease
• Can be used for routine evaluation of early joint changes
• For hemarthrosis evaluation, MSKUS detected low
concentrations of intra-articular blood (as low as 5%)
and discriminated between bloody and non-bloody fluid

Additional Methods to Assess Joint Bleeds and Joint Health
Gouw et al, 2019; St-Louis et al, 2022.
Joint Health
Measurement
Age Physical Examination Scores
World Federation
of Hemophilia
Orthopaedic
Joint Score
(WFH)
Children and
adults
• Hemophilia-specific physical examination for joint
health of the knees, ankles, and elbows
• An additive score ranging from 0-12 for knees and ankles and
0-10 for elbows, with 0 being an unaffected joint and 10 or 12
being most affected
• The maximum total score is 68 without the pain score and 86
with the pain score (0-3 for each joint)
• Used to develop the CPE, PJS, and HJHS
Colorado Physical
Examination Scale
(CPE)
Children
• The original CPE assessed the knee, ankle, and
elbow to detect subtle abnormalities in joint
health
• Scores range from 0-31 for ankles/knees and 0-29 for elbows
• Higher scores indicate worse joint health
The Petrini Joint
Score
(PJS)
Adapted from
the WFH scoring
system for use in
children
• 3 points can be added when the joint is
considered a target joint and when chronic
synovitis is present
• Ankles, knees, and elbows are assessed
• Scores range from 0-25 per joint, with a maximum total
score of 150
• Higher scores indicate worse joint health
Hemophilia Joint
Health Score
(HJHS)
Originally
designed for
children, but now
validated in
adults
• Originally designed to detect mild joint
impairment in knees, ankles, and elbows
• Current version (2.1) assesses swelling, duration
of swelling, muscle atrophy, crepitus on motion,
flexion loss, extension loss, joint pain, global gait,
and strength of the knees, elbows, and ankles
• Incorporates scoring of the WFH, CPE, and PJS
• The maximum score is 124, with a higher score indicating
worse joint health (version 2.1)
• Version 1: max score was 148
Despite existing gaps in the evidence for all measurements, HJHS properties were most extensively studied
and are used in clinical practice in young adults treated intensively and in children

Why Do We Need
Nonfactor Therapies?

Prophylaxis Schedule: Month
Slide courtesy of Guy Young, MD.
Sunday Monday Tuesday Wednesday Thursday Friday Saturday

Prophylaxis Schedule: Year
And that is just
the first year…

IV = intravenous.
Prophylactic Schedule With Extended Half-Life Factor VIII
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
104 IV injections
per year

Parents Don’t Like It…Kids Hate It!
Image courtesy of Guy Young, MD.
Prophylaxis for Hemophilia
And this is a good
day, Dr. Young

This was for 1
infusion!!
Prophylaxis for Hemophilia
Image courtesy of Guy Young, MD.

Callaghan et al, 2018.
Improve joint outcomes
By reducing bleeding events including
subclinical bleeding
Reduce the treatment burden
For intravenous therapies, reduce the frequency
of infusions
Subcutaneous administration (most new
medications and those being developed are
given subcutaneously)
Oral administration—today this is still just a
dream
Eliminate the treatment burden—gene therapy?
Improve quality of life
Allow for patients to live a “hemophilia-free life”
Goal of New Therapies

AAV = adeno-associated virus.
Callaghan et al, 2018; Miesbach et al, 2022.
Novel factor therapies
Efanesoctocog alfa
Nonfactor therapies
FVIII mimetics
Rebalancing agents
Gene therapy
AAV transfer
Lentiviral transfer
Gene editing
Categories of Novel Therapies

XI XIa
Ca++
IX IXa
Ca++
X Xa
Ca+
+
VIIIa
VIII
VII
VIIa
TF
Xa
X
Ca++
Prothrombin (II) Thrombin (IIa)
Fibrinogen (I) Fibrin
XIII
XIIIa
Cross-linked fibrin
V Va
Thrombin (IIa)
Antithrombin
Protein C
Protein Ca
Thrombin (IIa)
Protein
S
Protein
S
Thrombin (IIa)
Ca++
Tissue factor pathway
inhibitor (TFPI)
Emicizumab
MIM8
NXT007
Concizumab
Marstacimab
MG1113
Fitusiran
Serpin PC
Anti-APC Mab
Anti-PS Mab
Anti-PS siRNA
Anti-PS Mab
Anti-PS siRNA
Efanesoctocog alfa
Gene therapy
Gene therapy
PS = phosphorothiotate;
Mab = monoclonal antibody;
TF = tissue factor;
Ca = calcium;
APC = antigen-presenting cell.
Young, 2023.
Novel Therapeutics Mechanisms of Action
Inhibits
Replacement therapy
Substitution therapy
Rebalancing agents

Improving on Current
Factor Therapy

Novel Factor Therapy
Lissitchkov et al, 2022.
MOA Drug
Dosing
Regimen
Development
Phase
Comments
Factor
replacement
(non-inhibitor
patients)
Efanesoctocog
alfa (efa)
IV weekly Approved
Higher factor levels
throughout the dosing
interval (~70%-15%) than
current factor products

Structure of BIVV001
VWF = von Willebrand factor.
Konkle et al, 2020.

BIVV001 Efficacy: Factor IVVV Activity at 14 Days
Konkle et al, 2020.
Group Receiving Dose of 65 IU/kg

0
0.5
1
1.5
2
2.5
3
3.5
Annual Bleed Rate
SOC Prophylaxis Efanesoctocog alfa
Primary Endpoint
Efanesoctocog Alfa Clinical Results
SOC = standard of care.
von Drygalski et al, 2023.
SOC Prophylaxis Efanesoctocog alfa

von Drygalski et al, 2023.
No serious adverse effects
No inhibitors
No thrombosis
No allergic reactions
Efanesoctocog Alfa Safety

Nonfactor Therapies
Young, 2023.
They are all given subcutaneously and most
of them less/much less frequently than
factor therapy
They are (based on trial data) more effective
at preventing bleeding than factor therapy
They therefore may be more effective at
preventing joint disease

XI XIa
Ca++
IX IXa
Ca++
X Xa
Ca+
+
VIIIa
VIII
VII
VIIa
TF
Xa
X
Ca++
XIII
XIIIa
Cross-linked fibrin
V Va
Thrombin (IIa)
Antithrombin
Protein C
Protein Ca
Thrombin (IIa)
Protein
S
Protein
S
Thrombin (IIa)
Ca++
inhibitor (TFPI)
Emicizumab
MIM8
NXT007
Concizumab
Marstacimab
MG1113
Fitusiran
Serpin PC
Anti-APC Mab
Anti-PS Mab
Anti-PS siRNA
Anti-PS Mab
Anti-PS siRNA
Efanesoctocog alfa
Inhibits
Replacement therapy
Rebalancing agents

Factor VIII Mimetics (For Hemophilia A Only)
SC = subcutaneous; Q = every; prophy = prophylaxis; Hem = hemophilia.
Hemlibra® prescribing information, 2025; Hermans et al, 2024; Shima et al, 2025.
MOA Drug
Dosing
Regimen
Development
Phase
Comments
Substitute
for the
function of
activated
FVIII
Emicizumab
SC Q1, 2, or 4
weeks
Approved
Most commonly prescribed
medication for prophy in Hem A
Mim8
SC Q1 week or
Q1 month
3 Preclinical studies show
increased thrombin generation
compared to emicizumab
NXT007
SC Q1, 2 or 4
weeks?
1

Factor VIII Mimetics (Hemophilia A Only)
Kitazawa et al, 2012.

Emicizumab: Efficacious in Severe + Non-Severe Hemophilia A
Callaghan et al, 2021.
• With nearly 3 years of
follow-up, low bleed rates
were maintained with
emicizumab prophylaxis
• After Week 24, at least
97% of participants had
≤3 bleeds in each
treatment interval
• Emicizumab remained
well-tolerated over long-
term follow-up

Severe Muscle Bleeds in Hemophilia A Patients on Emicizumab?
BE = bleeding event.
Batsuli et al, 2023.
Median (range) age at time of BE
Inhibitor patients: 13 (13-27) years
Non-inhibitor patients: 14 (10-21) years Iliopsoas (n=3)
Calf (n=3)
Sites of muscle bleeds
Non-inhibitor
patients (n=11)
Inhibitor
patients (n=4)
Thigh (n=6)
Forearm (n=1)
Lower leg (n=1)
Iliopsoas (n=2)
Thigh (n=2)
Forearm (n=1)
BEs (n=14)
BEs (n=5)
Thigh and iliopsoas were the most common sites
of the muscle bleeds
7
2
Spontaneous 6 Sports/activity–
related
Weight-lifting–
related
4
Other trauma-
induced
Type of bleed
19 severe muscle bleeds occurred in the 15 hemophilia A patients

Mim8
HA = hemophilia A; CFC = clotting factor concentrates.
Lillicrap et al, 2024; Mancuso et al, 2024; Østergaard et al, 2021; GlobeNewswire, 2025.
IgG anti-FIXa/anti-FX bispecific
antibody with unique
binding sites
13-18–fold enhanced activity
compared to emicizumab
FVIII bioequivalence up to 36.8%
(assay-dependent)
FRONTIER2
Phase 3, adolescents and adults with
HA with or without inhibitors
Improved ABR with
either weekly or monthly
dosing compared to
prior CFC prophylaxis
FRONTIER3 interim
analysis with 74% of
children with 0 treated
bleeds on weekly injections

Activity of Mim8: Peak Thrombin Generation
biAb = bispecific antibody; SIA = sequence identical analogue.
Østergaard et al, 2021.

FRONTIER2: Mim8 Efficacy
QW = every week;
QM = every month.
Mancuso et al, 2024.
FRONTIER2: phase 3 trial of Mim8 in 254 patients ≥12 years of age with hemophilia A
with or without inhibitors
Mim8: investigational FVIII mimetic that is approximately 15 times more potent in
vitro than emicizumab

FRONTIER2: Mim8 Efficacy (cont.)
ad/c in Arm 2a due to nerve paralysis of probably relation to Mim8; d/c in Arm 3 due to sleep disorder and dyspepsia possibly related to Mim8 and
coronary artery disease unlikely to be related to Mim8.
Mancuso et al, 2024.
Safety Summary
No evidence of neutralizing antibodies targeting Mim8
Rates of injection-site reactions were low (9.5% in Arm 2a, 5% in Arm 2b, 12.2% in Arm 3, and 8.2% in Arm
4)
Pre-Study On-Demand Treatment Group Pre-Study CFC Prophylaxis Group
Arm 1,
On Demand
(n=17)
Arm 2a,
Mim8 QW
(n=21)
Arm 2b,
Mim8 QM
(n=20)
Arm 3, Mim8 QW Arm 4, Mim8 QM (n=98)
Run-in
(n=98)
Main
(n=98)
Run-in
(n=98)
Main
(n=98)
Total exposure time, yr 8.41 9.94 9.93 77.07 46.62 73.76 48.7
All AEs, n (%) 5 (29.4%) 10 (47.6%) 6 (30.0%) 58 (59.2%) 71 (72.4%) 51 (52.0%) 65 (66.3%)
Serious AEs, n (%) 1 (5.9%) 1 (4.8%) 0 6 (6.1%) 4 (4.1%) 2 (2.0%) 4 (4.1%)
Thromboembolic events,
n (%)
0 0 0 0 0 0 0
Severe AEs, n (%) 1 (5.9%) 2 (9.5%) 0 1 (1.0%) 2 (2.0%) 2 (2.0%) 3 (3.1%)
AE related Mim8, n (%) 0 4 (19.0%) 1 (5.0%) 0 20 (20.4%) 0 17 (17.3)
AE leading to Mim8 d/c,a
n (%)
0 1 (4.8%) 0 0 2 (2.0%) 0 0

NXT007
IgG = immunoglobulin G. Teranishi-Ikawa et al, 2024; NCT05987449.
IgG anti-FIXa/anti-FX bispecific
antibody
30-40x higher affinity than
emicizumab
Activity similar to emicizumab
but at 30-fold lower
concentration
Phase 1/2 trial recruiting
adolescent and adults with
moderate/severe HA with or
without inhibitors
Potential near-normal
hemostatic state

Tissue Factor Pathway Inhibitor (TFPI)
Chowdary, 2018.
TFP
I
Tissue factor
+ FVIIa
FIXa
(+ FVIIa)
FXa
(+ FVa)
FIIa
(thrombin)
Fibrinogen Fibrin
X
Anti-TFPI antibody
against K2 domain
Anti-TFPI antibody
against K1 and K2
domains
Anti-TFPI
TFPI
TFPI
VIIa
TF
X Xa
VIIa
TF
X Xa
VIIa
TF
X Xa

Marstacimab
IgG1 = immunoglobulin G1; FXa = factor Xa.
Kwak et al, 2020.
Monoclonal Antibody Targeted Against TFPI
TFPI-K2
Marstacimab-HC
Marstacimab-LC
R107
Marstacimab is a human IgG1
monoclonal antibody against TFPI that
targeting the K2 domain, blocking its
ability to inhibit FXa and preventing the
binding of the K1 domain to FVIIa

Once-Weekly Marstacimab-hncq
HympavziTM et al, 2024.
First and only subcutaneous prophylactic treatment in hemophilia A or
B without inhibitors that comes in a fixed-dose, prefilled pen
Marstacimab-hncq is indicated for routine prophylaxis to prevent or
reduce the frequency of bleeding episodes in adult and pediatric
patients 12 years of age and older with:
Hemophilia A (congenital factor VIII deficiency) without factor VIII
inhibitors
Hemophilia B (congenital factor IX deficiency) without factor IX inhibitors
Marstacimab-hncq
Injection
150 mg/mL

BASIS: Efficacy and Safety of Marstacimab
ATP = active treatment phase.
Matino et al, 2023; Mahlangu, 2025.
On-demand treatment
with FVIII/FIX
Current SOC (n=37)
Routine prophylaxis
with FVIII/FIX
Current SOC (n=91)
With
FVIII/FIX
inhibitors
(ongoing)
Male patients aged ≥12
years and ≥35 kg with
severe hem A or hem B
Dose escalation of marstacimab (optional)
~45-day
screening
6-month observation
N=128
12-month open-label active treatment
N=116
Following the 12-month ATP,
eligible patients could opt-in
to participate in an open-label
extension study
Open-label extension
N=87
Without
FVIII/FIX
inhibitors
n=128
Marstacimab prophylaxis
Single SC loading dose of
300 mg followed by QW 150 mg
Marstacimab
prophylaxis continued

BASIS: Marstacimab (cont.)
OD = on-demand; RP = routine prophylaxis.
Acharya et al, 2024; NCT03938792.
Eligibility Criteria for Non-Inhibitor Cohort
• Patients with a history of coronary artery disease, venous
or arterial thrombosis, or ischemic disease were excluded
from the study
• Scheduled surgery during study period
• Platelet count <100,000/µL
• Hemoglobin level <10 g/dL
• Current RP with bypassing agent, noncoagulation
nonfactor replacement therapy, or any previous gene
therapy product
• Current immunomodulatory drugs
• Severe hem A (FVIII <1%) without inhibitors or severe
hem B (FIX ≤2%) without inhibitors
• Male, ≥12 to <75 years of age, minimum weight
of 35 kg at screening
• No detection or history of inhibitors against FVIII
or FIX
• OD group: ≥6 acute bleeding episodes
(spontaneous or traumatic) that required
coagulation factor infusion during the 6-month
period prior to enrollment
• RP group: ≥80% compliance with FVIII/FIX
regimen 6 months prior to enrollment
Select Inclusion Criteria Select Exclusion Criteria

OP = observational phase.
Matino et al, 2023.
On-Demand (OD) Arm
Marstacimab during ATP
(n=33)
Superior vs On-Demand
50
40
30
20
10
0
Mean
ABR
for
treated
bleeds
(95%
CI)
38.00
(95% CI:
31.03, 46.54)
On-demand during OP
(n=33)
3.18
(95% CI: 2.09, 4.85)
92% Reduction
P<0.0001
12-month ATP
6-month OP
Median ABR 35.73 2.02

Matino et al, 2023.
Routine Prophylaxis Arm
Marstacimab during ATP
(n=83)
Non-Inferior vs Routine Prophylaxis
15
10
5
0
Mean
ABR
for
treated
bleeds
(95%
CI)
7.85
(95% CI:
5.09, 10.61)
Routine prophylaxis during OP
(n=83)
5.08
(95% CI:
3.40, 6.77)
35% Reduction
12-month ATP
6-month OP
Median ABR 2.16 2.02

Anti-Drug Antibodies
ADAs including NAbs had no identified
clinically significant effect on safety or efficacy
of marstacimab over the treatment duration
of 12 months
23/116 patients tested positive for ADAs
(19.8%)
NAb development was low at 6/23 (26.1%)
PI = prescribing information; ADAs = anti-drug antibodies; NAbs = neutralizing antibodies.
Matino et al, 2023
Safety
Adverse Reaction Number of Patients (N=116), n (%)
Injection site reaction 11 (9%)
Headache 8 (7%)
Pruritus 4 (3%)
In the BASIS study, the majority of adverse reactions were mild-to-moderate
and there were no reported discontinuations due to treatment-related
adverse reactions. See PI for guidance on when to discontinue
marstacimab.
Adverse Reactions Reported in ≥3% of Patients Treated With Marstacimab
During the BASIS Trial 12-Month Active Treatment Phase

Concizumab-mtci
Alhemo® prescribing information, 2025.
Concizumab-mtci is a tissue factor pathway inhibitor (TFPI)–
antagonist indicated for routine prophylaxis to prevent or reduce
the frequency of bleeding episodes in adult and pediatric patients
12 years of age and older with:
Hemophilia A with or without FVIII inhibitors
Hemophilia B with or without FIX inhibitors
Concizumab-mtci
150 mg/1.5 mL
(100 mg/mL)

Mean ABR was 1.7 and median ABR was 0, and 64% of participants who received
concizumab (Arm 2, n=33) had 0 treated bleeds at 24 weeks
9.8
(6.5; 20.2)
0.0
(0.0; 3.3)
0
2
4
6
8
10
12
14
No prophylaxis
(n=19; arm 1)
Concizumab prophylaxis*
(n=114;
arms 2–4)
Median
ABR
(IQR)
Concizumab prophylaxis
(arm 2; n=33)
No prophylaxis
(arm 1; n=19)
11.8
(7.0; 19.9)
1.7
(1.0; 2.9)
0
2
4
6
8
10
12
14
Mean
ABR
(95%
CI)
explorer7: Concizumab
aIncludes participants previously on demand that were randomized to receive concizumab prophylaxis (Arm 2. n=33), participants that transferred from
the explorer4 trial, and an additional group of participants that were on prior prophylaxis or on demand (Arms 3 and 4, respe
ctively, n=81).
IQR = interquartile range.
Jiménez Yuste et al, 2022; Mathias et al, 2023.
Phase 3 Efficacy Data
ABR at Primary Analysis Cutoffa in People With Hemophilia A or B With Inhibitors

Treated spontaneous and
traumatic bleeding episodes
HAwI
No PPX
(Arm 1; n=9)
HAwI
Concizumab
PPX
(Arm 2; n=18)
ABR ratio
(95% CI)
HBwI
No PPX
(Arm 1; n=10)
HBwI
Concizumab
PPX
(Arm 2; n=15)
ABR ratio
(95% CI)
Estimated mean ABR
18.3
(10.2-32.9)
1.6
(0.9-2.8)
0.09
(0.04-0.18)
7.2
(2.6-20.1)
2.2
(0.8-6.5)
0.31
(0.07-1.36)
Treated spontaneous and
traumatic bleeding episodes
HAwI
Concizumab PPX (Arms 1-4; n=76)
HBwI
Concizumab PPX (Arms 1-4; n=51)
Overall median ABR (IQR) 0.0 (0.0-3.7) 0.0 (0.0-3.3)
Number of episodes 128 152
explorer7: Concizumab (cont.)
HAwI = hemophilia A with inhibitors; HBwI = hemophilia B with inhibitors.
Frei-Jones et al, 2022; Jiménez Yuste et al, 2022.
Efficacy results were consistent when split by hemophilia subtype

aIncludes Arm 1 participants who started concizumab treatment in the extension part of the trial, and Arm 2-4 participants.
Jiménez Yuste et al, 2022.
n (%) No Prophylaxis
Concizumab Prophylaxis
(Arm 2)
Concizumab Prophylaxis
(All Participantsa)
Total events 8 (42.1%) 20 (60.6%) 80 (63.0%)
Serious events 3 (15.8%) 6 (18.2%) 14 (11.0%)
Fatal events 1 (5.3%) 2 (6.1%) 2 (1.6%)
Drug withdrawn 0 2 (6.1%) 4 (3.1%)
Thromboembolic events 0 1 (3.0%) 1 (0.8%)
Thromboembolic events after
restart
0 0 0
Hypersensitivity-type
reaction
0 1 (3.0%) 2 (1.6%)
Injection-site reaction 0 6 (18.2%) 26 (20.5%)

Estimated Treatment Difference for Hemo-TEM Scores
CZM = concizumab; ETD = estimated treatment difference; Hemo-TEM = Hemophilia Treatment Experience Measure; PPX = prophylaxis.
Hampton et al, 2023.
HRQOL Was Improved With Concizumab in the Phase 3 explorer7
Study

Concizumab Phase 3 Trials
SD = standard deviation.
Windyga et al, 2024.
Efficacy at 56-Week Cutoff
explorer7 explorer8
HAwI HBwI HA HB
No. patients in full analysis set 76 51 80 64
Cumulative years of exposure in
data analysis set
84.3 56.2 111.9 71.7
Treated Spontaneous and Traumatic Bleeding Episodes
Median ABR (IQR) 0.7 (0.0-3.0) 1.1 (0.0-3.2) 1.7 (0.0-4.5) 2.8 (0.0-6.4)
Mean ABR (SD) 2.1 (4.1) 4.3 (11.5) 3.9 (6.6) 6.4 (14.2)
Min; max ABR 0.0; 31.8 0.0; 66.4 0.0; 37.1 0.0; 91.3

Concizumab Phase 3 Trials (cont.)
aSafety analysis set. PYE = patient-years of exposure.
Windyga et al, 2024.
Efficacy at 56-Week Cutoff
explorer7: HAwI/HBwI (n=127a) explorer8: HA/HB (n=151a)
n (%)
No. of
Events
Events/
PYE
n (%)
No. of
Events
Events/PYE
Total AE 91 (71.7%) 467 2.9 118 (78.1%) 528 2.7
Serious AE 22 (17.3%) 27 0.2 20 (13.2%) 30 0.2
Fatal AE 4 (3.1) 6 0.0 1 (0.7%) 1 0.0
AE leading to drug withdrawal 4 (3.1%) 4 0.0 6 (4.0%) 8 0
TE prior to tx pause 1 (0.8%) 1 0.0 2 (1.3%) 4 0.0
TE from tx restart to 56-wk cutoff 0.0 0.0 - 0 - -
Hypersensitivity 2 (1.6%) 2 0.0 0 - -
Injection site reactions 30 (23.6%) 60 0.4 26 (17.2%) 46 0.2
Medication errors 4 (3.1%) 6 0.0 4 (2.6%) 5 0.0
• Fatal events:
– explorer7: COVID-19 (n=1), intracranial hemorrhage (n=1), alcoholic coma (n=1), and 1 patient with fatal humerus
fracture, femur fracture, and road traffic accident
– explorer8: intra-abdominal hemorrhage (n=1)

XI XIa
Ca++
IX IXa
Ca++
X Xa
Ca+
+
VIIIa
VIII
VII
VIIa
TF
Xa
X
Ca++
XIII
XIIIa
Cross-linked fibrin
V Va
Thrombin (IIa)
Antithrombin
Protein C
Protein Ca
Thrombin (IIa)
Protein
S
Protein
S
Thrombin (IIa)
Ca++
inhibitor (TFPI)
Emicizumab
MIM8
NXT007
Concizumab
Marstacimab
MG1113
Fitusiran
Serpin PC
Anti-APC Mab
Anti-PS Mab
Anti-PS siRNA
Anti-PS Mab
Anti-PS siRNA
Efanesoctocog alfa
Inhibits
Replacement therapy
Rebalancing agents

Targeting Antithrombin: Fitusiran
Young, Srivastava et al, 2023; Srivastava et al, 2023; Kenet et al, 2024; NCT03974113; NCT03754790.
Small interference RNA →
degradation of mRNA
Monthly subcutaneous
injection
ATLAS Clinical Trial Program

Fitusiran
BPA = bypassing agent; CPC = clotting factor concentrate; ALT = alanine aminotransferase; AST =aspartate aminotransferase; ULN = upper limit of normal.
Young, Srivastava et al, 2023; Srivastava et al, 2023; Kenet et al, 2022.
Study population
People with haemophilia A or B
aged ≥12 years with inhibitors (N=57)
received fitusiran 80 mg prophylaxis or
on-demand BPAs
aged ≥12 years without inhibitors
(N=120) received fitusiran 80 mg
prophylaxis or on-demand CFCs
aged ≥12 years with or without inhibitors
(N=80) with prior BPA/CFC prophylaxis
received fitusiran 80 mg prophylaxis
Efficacy
Safety
91% reduction in bleeding rates
compared with on-demand BPAs
(P<0.0001); median ABR was 0.0
compared with on-demand CFCs
(P<0.0001); median ABR was 0.0
compared with prior BPA/CFC
prophylaxis (P=0.0008); median ABR was
0.0
Completed Phase 3
Trials
Thrombotic events:
2 participants (5.0%)
ALT/AST elevations 3x ULN:
Thrombotic events:
none
Thrombotic events:
Mean AT levels (SD) 10.7% (2.9) 11.8% (4.0) 11.0% (2.5)
Fitusiran has been studied in the largest pre-approval hemophilia cohort to date,
with 335 participants exposed from 24 countries

Revised AT-Based Dosing Regimen
QM = every month; SS = steady state; AT = antithrombin.
Pipe et al, 2022; Young, Lenting, et al, 2023; Young et al, 2024.
Designed to Enhance the Benefit-Risk Profile of Fitusiran
>1 AT level <15%
≥2 SS AT levels >35%
>1 AT level <15%
Revised AT-based dosing regimen targeting an AT level of 15%-35%
Original dose
regimen
80 mg QM
Regular AT monitoring was
used to guide dosing
Lower-dose cohort for
participants requiring
<50 mg Q2M
20 mg QM
80 mg QM
20 mg Q2M
50 mg Q2M
50 mg QM
Discontinue

Approved AT-Based Dose Modification
Qftlia prescribing information, 2025.
Initial dose:
50 mg Q2M
Measure AT activity at
Month 1, 3, 5, and 6
following the starting
dose and after any
dose modification
Last Dosage
Administered
Antithrombin Activity Level Dose Modification
50 mg Q2M
<15% 20 mg Q2M
15%-35% Continue current dosage
>35% after 6 months 50 mg Q1M
20 mg Q2M
<15% 10 mg Q2M
>35% after 6 months 20 mg Q1M
10 mg Q2M
<15% Discontinue fitusiran
>35% after 6 months 10 mg every month

Revised AT-Based Dosing Regimen (cont.)
a80 participants (38%) required 0 and 119 (56%) required 1 dose change to achieve AT range 15%-35%.
Pipe et al, 2022; Young, Lenting et al, 2023; Young et al, 2024.
Achieved Its Aim of Maintaining AT Levels Between 15%-35%
AT value by visit during primary efficacy period
• 78% (n=167) were on Q2M regimens at final dose
• 94% (n=199) required 0 or 1 dose adjustment to achieve AT 15%-35%
Mean (SD) AT level was 23.5%
(4.6) with the AT-DR
0
10
20
30
40
50
60
Month 7 Month 8 Month 9 Month 10 Month 11 Month 12 Month 13
Study Visit
Antithrombin
level
(%)

Thrombotic Events
AT-DR = antithrombin-based dose regimen; ODR = original dose regimen;
TEAESI = thrombotic event adverse event of special interest; TE = thrombotic event.
Young et al, 2025.
TEAESIs, n (%)
AT-Based Dose Regimen
(n=286)
Original Dose Regimen
(n=270)
Thrombotic events 4 9
Participants with any thrombotic events (%) 4 (1.4) 7 (2.6)
Exposure adjusted incidence rate (per 100 patient years) 0.82 2.28
Based on a recently submitted abstract on Optum claims database analysis,
the rate of TEs with the AT-DR are similar to the general hemophilia population
2.28
0.82
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Original dose regimen (N=270) AT-based dose regimen (N=286)
Exposure
adjusted
incidence
rate
(per
100
patient-years)
Incidence of thrombotic events
Incidence of Thrombotic Events Was Reduced With AT-DR vs ODR

Young et al, 2025.
TEAESIs, n (%)
(n=286)
(n=270)
Cholecystitis/Cholelithiasis
Participants with any Cholecystitis/Cholelithiasis 11 (3.8%) 45 (16.7%)
TEAESIs, n (%)
(n=286)
(n=270)
ALT/AST elevations > 3xULN
Participants with any ALT/AST elevations >3x ULN 10 (3.5%) 56 (20.7%)
Majority of ALT or AST elevations 3x ULN with the AT-DR were transient and reported as recovered/resolved,
with a median of 212 and 186 days to onset and median time to normalisation of 88 and 49 days, respectively
ALT/AST Elevations and Cholecystitis/Cholelithiasis
Incidence of ALT/AST elevations 3x ULN and cholecystitis/cholelithiasis
was substantially reduced with AT-DR vs ODR

Young et al, 2025.
1.9
(0.0; 5.6)
3.8
(0.0; 11.2)
3.7
(0.0; 7.5)
0
2
4
6
8
10
Inhibitor (n=69) Non-inhibitor (n=128) Overall (N=197)
Median
ABR
(IQR)
Observed median ABR with the fitusiran AT-DR Proportion of participants with 0 or 1 bleed
in the primary efficacy period:
31.5%
37.7%
28.1%
0 Bleeds
47.2%
53.6%
43.7%
0-1 Bleeds
80
Fitusiran AT-DR provided clinically meaningful bleed control in participants with
hemophilia A and B with and without inhibitors
ATLAS-OLE: Fitusiran AT-DR

Properties of Rebalancing Agents
Young et al, 2024; Alhemo® prescribing information, 2025; HympavziTM et al, 2024; Matino et al, 2025.
MOA Drug
Dosing
Regimen
Development
Phase
Comments
Anti-AT
siRNA
Fitusiran
SC monthly or
every other
month
Approved
Thrombotic events led to a new dosing
regimen targeting AT levels between
15%-35%
Anti-TFPI
monoclonal
antibodies
Concizumab SC daily Approved
Dose to be adjusted based on
concizumab levels
Marstacimab SC weekly Approved Dosing does not require adjustment

Patient Case: Hemophilia A (cont.)
14-year-old male with severe hemophilia A with
history of transient inhibitor
Baseline FVIII <1%
Trial of emicizumab for 12 months; developed a
large muscle bleed but wants to know his options

Polling Question
What is known about muscle bleeds in patients on emicizumab?
a. Emicizumab does not prevent muscle bleeds
b. Emicizumab is only effective against joint bleeds
c. There are reports of serious muscle bleeds especially in
teenagers and young adults on emicizumab
d. Factor concentrates are proven to be more effective against muscle
bleeds that emicizumab

Polling Question
Which of the following options could be considered for this
patient?
a. Efanesoctocog alfa (though this would mean going from a
subcutaneous drug to an intravenously administered drug)
b. Switch to fitusiran
c. Switch to concizumab
d. Switch to marstacimab
e. All of the above

Patient Case: Hemophilia B
Baseline FIX <1%
Day 7 (2%) and ABR~3
Wants to consider alternative therapy as he is getting
“tired” of frequent injections

Polling Question
What are the novel options for prophylaxis for a young adult with
severe hemophilia B?
a. Factor replacement (SHL and EHL products) are the only option
b. An anti-TFPI subcutaneous drug such as concizumab or
marstacimab
c. An siRNA subcutaneous option such as fitusiran monthly or
every 2 months
d. Options b and c are reasonable for prophylaxis

Strategies for Advanced Therapies in Hemophilia
LV = lentiviral gene therapy;
MSC = mesenchymal stem cell;
CRISPR = clustered regularly interspaced
short palindromic repeats;
ZFN = zinc-finger nuclease.
Rodríguez-Merchán et al, 2021.
Advanced Therapies
Gene Therapy Cell Therapy
IN VIVO
AAVs LVs
EX VIVO
MSCs
CRIPSR
ZFN
(AAVs)

FVIII Activity (mITT Population)
CSA = chromogenic substrate assay; mITT = modified intention-to-treat; Q = quartile; SE = standard error.
Leavitt et al, 2025.
Nearly Stable Compared to Year 4
Week 260
Mean ± SE: 13.7 ± 2.1 IU/dL
Median (Q1, Q3): 6.2 (2.4, 14.2) IU/dL
Week 208
Mean ± SE: 15.9 ± 2.5 IU/dL
Median (Q1, Q3): 6.5 (2.8, 17.7) IU/dL
Week 156
Mean ± SE: 18.4 ± 2.7 IU/dL
Median (Q1, Q3): 8.3 (3.0, 17.2) IU/dL
Mean
±
SE
FVIII
activity
(IU/dL)
0
20
40
60
80
100
Study week
4 28 52 76 104 128 156 180 208 232 260
mITT population
n = 132 132 132 132 132 132 132 132 132 132 132
For participants who discontinued the study, missing FVIII values post-discontinuation were imputed as 0 IU/dL through the data cutoff date.

Valoctocogene Roxaparvovec (cont.)
CI = confidence interval.
Annualized Rate of Treated Bleeding Episodes
0
5
10
15
Mean + SD Median (Q3)
83.3%
reduction
Change in mean,
−4.02 (95% CI, −5.24 to −2.80);
P<0.0001
112 112 110 110
112 108
n= 112
2.8
0 0
0 0
0
0.2
4.8
0.9
0.7
1.0
0.9
0.6
0.8
ABR
(bleeds/year)
Baseline Year
1
Year
2
Year
3
Year
4
Year
5
All
post-
prophylaxis

Valoctocogene Roxaparvovec (cont.)
Annualized Rate of Factor VIII Use
Baseline Year 1 Year 2 Year 3 Year 4 Year 5 All post-
prophylaxis
0
50
100
150
200
250
128.6
0 0 0 0 0 0.8
135.9
1.5
3.4
8.6
10.7 10.6
6.9
Change in mean, −129.0 (95% CI, −138.6 to −119.3); P<0.0001
112 112 110 110
112 108
n = 112
94.9%
reduction
AFR
(infusions/year)
Mean + SD Median + Q3

Participants, n (%)
Year 1
(N=134)
Year 2
(N=134)
Year 3
(N=132)
Year 4
(N=131)
Year 5
(N=129)
All
Follow-Up
AEs 134 (100.0%) 112 (83.6%) 104 (78.8%) 98 (74.8%) 102 (79.1%) 134 (100.0%)
SAEs 21 (15.7%) 6 (4.5%) 9 (6.8%) 11 (8.4%) 4 (3.1%) 37 (27.6%)
Treatment-related AEsa 124 (92.5%) 27 (20.1%) 15 (11.5%) 10 (7.6%) 5 (3.9%) 124 (92.5%)
Glucocorticoid-related AEsa 81 (60.4%) 10 (7.5%) 1 (0.8%) 1 (0.8%) 0 82 (61.2%)
AEs of
special
interest
ALT elevation 116 (86.6%) 39 (29.1%) 31 (23.7%) 49 (37.4%) 52 (40.3%) 125 (93.3%)
ALT elevation grade ≥3 10 (7.5%) 1 (0.7%) 0 0 0 10 (7.5%)
Potential Hy’s law case 0 0 0 0 0 0
Infusion-related reactionsb 12 (9.0%) 0 0 0 0 12 (9.0%)
Systemic hypersensitivity 7 (5.2%) 0 0 0 0 7 (5.2%)
Anaphylactic or anaphylactoid
reactions
3 (2.2%) 0 0 0 0 3 (2.2%)
Thromboembolic events 0 0 0 0 0 0
Anti-FVIII neutralizing antibodies 0 0 0 0 0 0
Malignancy (except nonmelanoma
skin cancer)
0 0 1 (0.8%) 0 0 1 (0.7%)
Valoctogene Roxaparvovec (cont.)
aTreatment-related and glucocorticoid-related adverse events (AEs) were assessed by the investigator.
bInfusion-related reactions were defined as AEs occurring during valoctocogene roxaparvovec infusion or within 6 hours post-infusion.
ITT = intention-to-treat; SAE = serious AE.
Safety

Gene Therapy to Deliver Factor IX
Pipe, 2025.
Etranacogene Dezaparvovec

Etranacogene Dezaparvovec
Pipe, 2025.
Endogenous Factor IX Activity Over 18 Months After Treatment

Etranacogene Dezaparvovec (cont.)
Pipe, 2025.
Annualized Bleeding Rate
60% (31/54) of participants experienced no joint bleeds over 0-4 years post-treatment

Etranacogene Dezaparvovec (cont.)
Pipe, 2025.
Changes in Factor Consumption and Number of Infusions
Of 54 participants treated with etranacogene dezaparvovec:
• 2 participants remained on continuous FIX prophylaxis post-infusion (high NAb) titer of 3,212, n=1; ~10% of the dose,
n=1
• 94.4% (51/54) participants discontinued continuous FIX prophylaxis at 4 years
• 1 participant returned to continuous FIX prophylaxis 30 months following infusion
46.3% (25/54) of participants received no FIX infusion over the 4-year period post-treatment
infusions

aPlanned as only 1 infusion total.
Srivastava et al, 2020; Hemlibra® prescribing information, 2025; Hermans et al, 2024; Shima et al, 2025; Young et al, 2024;
Alhemo® prescribing information, 2025; Hympavzi et al, 2024; Matino et al, 2025; Mahlangu et al, 2023; Pipe et al, 2023.
Drug/MOA Infusions Per Year Comments
Factor replacement 52-183
Only IV. Other administration methods have been
tried but have not worked well
Emi/Mim8/NXT007 13-52 Very long washout (months) with no antidote
Fitusiran 6-12
Very long washout (months) but antidote (AT
infusion) is available
Concizumab 365
Daily infusion, but advantage of rapid washout
No antidote
Marstacimab 52 No antidote
Gene therapy 1a No ability to reverse effects for better or worse
Novel Agents by Infusions Per Year

SHARE Decision Making Model
Dennison Himmelfarb et al, 2023.

Patient Categories
Age Hemophilia type Severity Inhibitor status
<18
years
>18 years Hem A Hem B Sev Mod Mild Positive Negative
Sev = severe; Mod = moderate.
Srivastava et al, 2020.
Patient Factors When Choosing Therapy

Patient Categories
<18
years
>18 years Hem A Hem B Sev Mod Mild Positive Negative
Patient Categories
Venous access Adherence Risk-averse Lifestyle (work or play)
Good Poor Good Bad No Med Yes Higher-risk job/active Sedentary

Patient Categories
<18 years >18 years Hem A Hem B Sev Mod Mild Positive Negative
Patient Categories
Venous access Adherence Risk-averse Lifestyle (work or play)
Good Poor Good Bad No Med Yes Higher-risk job/active Sedentary
Patient Categories
Age Cardiovascular risk factors Individual patient values
<65 >65 Yes No High efficacy vs low treatment burden

14-year-old male with severe hemophilia A with history
of transient inhibitor
Baseline FVIII <1%
Trial of emicizumab for 12 months; developed a large
muscle bleed but wants to know his options

14-year-old male with severe hemophilia A with history
of transient inhibitor
Additional history is that he is very active in sports,
including soccer and baseball, and he believes his muscle
bleed occurred while playing soccer
Continuing these sports is very important for him
He places the most value on a different therapy with one
that can provide him the highest protection from bleeding
and is not concerned as much about the treatment burden

Polling Question
Given the additional history, which of the following options would
you choose?
a. Efanesoctocog alfa
b. Switch to fitusiran
c. Switch to concizumab
e. All of the above

Efanesoctocog alfa provides factor levels ranging from a peak of
~100% to a trough of ~15%-20%
Emicizumab has a FVIII equivalence of about 10%-20%, and that level
is steady (no peaks and troughs)
It is not yet clear what the FVIII equivalence of fitusiran, concizumab,
or marstacimab are, though bleed protection (granted across different
trials with no head-to-head comparison) seems similar to emicizumab
Given all the options, this patient’s high value on participation in
sports means that his highest FVIII protection would come from
receiving efanesoctocog alfa

Patient Case: Hemophilia B (cont.)
Baseline FIX <1%
Day 7 (2%) and ABR~3
Wants to consider alternative therapy as getting “tired”
of frequent injections

Polling Question
FP = recombinant human albumin; N9:GP = nonacog beta pegol.
Which of the following options could be considered for this
patient?
a. Switch to FIX:FP product or N9:GP product
b. Switch to concizumab
c. Switch to fitusiran
e. All of the above

Baseline FIX <1%
On EHL FIX product currently and desires a change to a
non-IV product
He and his family chose marstacimab
Weekly administration, single subcutaneous injection

He and his family chose marstacimab
Weekly administration, single subcutaneous injection
He self injects weekly on the weekend
Feels more independent as he is in control of his meds
Day 1: loading dose
300 mg SC injection
Day 8: start once-weekly maintenance dose
150 mg SC injection once weekly

Key Takeaways
Over the past 3 years, 6 new medications have been approved
for hemophilia A and B—these include a novel factor therapy,
3 nonfactor therapies, and 2 gene therapies
Each has their pros and cons, and hemophilia treaters must
familiarize themselves with the properties, dosing regimen,
laboratory monitoring, and safety and efficacy for all of them
Through shared decision making, the best therapy for each
individual patient’s situation can be selected

References
Acharya SS, Matino D, Palladino A, et al (2024). Safety and efficacy of the anti-tissue factor pathway inhibitor marstacimab in participants with severe hemophilia without
inhibitors: results from the phase 3 BASIS trial and ongoing long-term extension study. Presented at the Thrombosis & Hemostasis Summit 2024. Abstract 206.
Alhemo® (concizumab-mtci) prescribing information. Novo Nordisk. Available at: accessdata.fda.gov/scripts/cder/daf/index.
Bakeer N & Shapiro AD (2019). Merging into the mainstream: the evolution of the role of point-of-care musculoskeletal ultrasound in hemophilia. F1000Res, 8:F10000 Faculty
Rev-1029 [Version 1]. DOI:10.12688/f1000research.16039.1
Batsuli G, Wheeler AP, Weyand AC (2023). Severe muscle bleeds in children and young adults with hemophilia A on emicizumab prophylaxis: real-world retrospective multi-
institutional cohort. Am J Hematol, 98(10):285-287. DOI:10.1002/ajh.27039
Boulden Warren B, Thornhill D, Stein J, et al (2020). Young adult outcomes of childhood prophylaxis for severe hemophilia A: results of the Joint Outcome Continuation Study.
Blood Adv, 4(11):2451-2459. DOI:10.1182/bloodadvances.2019001311
Calcaterra I, Iannuzzo G, Dell’Aquila F & Dario Di Minno MN (2020). Pathophysiological role of synovitis in hemophilic arthropathy development: a two-hit hypothesis. Front
Physiol, 11:541. DOI:10.3389/fphys.2020.00541
Callaghan MU, Negrier C, Paz-Priel I, et al (2021). Long-term outcomes emicizumab prophylaxis for hemophilia A with or without FVIII inhibitors from the HAVEN 1-4 studies.
Blood, 137(16):2231-2242. DOI:10.1182/blood.2020009217
Callaghan MU, Sidonio R & Pipe SW (2018). Novel therapeutics for hemophilia and other bleeding disorders. Blood, 132(1):23-30. DOI:10.1182/blood-2017-09-743385
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