PB0195 - Efanesoctocog Alfa Versus Emicizumab in the Prophylactic Treatment of Adolescents and Adults with Severe Hemophilia A Without Inhibitors: A Matching-Adjusted Indirect Comparison

Sunday, June 25, 2023

18:30 – 19:30 ET

Room: Exhibition

Co-Author(s)

Maria Teresa Alvarez-Román, MD, PhD

Associate Professor
Department of Hematology, University Hospital La Paz, Autonoma University of Madrid, Madrid, Spain
Madrid, Madrid, Spain

Co-Author(s)

Nana Kragh, MSc

Global HEOR Director
Sobi, Stockholm, Sweden
Stockholm, Stockholms Lan, Sweden
PG

Patricia Guyot

Evidence Synthesis NMA/ITC Lead Modeling
Sanofi, Cambridge, Massachusetts, USA
Cambridge, Massachusetts, United States
AW

Amanda Wilson

HEVA Business Partner - Rare Disease and Rare Blood Disorder Portfolio
Sanofi, Cambridge, Massachusetts, USA
Cambridge, Massachusetts, United States
PW

Piotr Wojciechowski

External consultant
Putnam PHMR, Krakow, Poland
krakow, Malopolskie, Poland
WM

Wojciech Margas

Senior Analyst, HEOR DA
Putnam PHMR, Krakow, Poland
Krakow, Malopolskie, Poland
MW

Marlena Wdowiak

Senior Analyst, HEOR DA
Putnam PHMR, Krakow, Poland
Krakow, Malopolskie, Poland
ES

Elena Santagostino

VP Medicine Development Lead for Haemophilia
Sobi, Basel, Switzerland
Basel, Stockholms Lan, Sweden

Presenting Author(s)

Alix Arnaud, MsC (she/her/hers)

Director, HEOR Rare Blood Disorders
Sanofi, Cambridge, Massachusetts, USA
Cambridge, Massachusetts, United States

Background: The XTEND-1 study (NCT04161495) demonstrated that once-weekly efanesoctocog alfa prophylaxis provided superior bleed protection versus prior standard of care Factor VIII treatments. However, there are no head-to-head clinical trials comparing efficacy of efanesoctocog alfa versus emicizumab.

Aims: To compare the efficacy of efanesoctocog alfa prophylaxis versus emicizumab in adolescent and adult patients with severe hemophilia A without inhibitors.

Methods: Data from the phase 3 XTEND-1 study were used for efanesoctocog alfa and results from a systematic literature review (SLR) (in Medline, EMBASE, and Cochrane clinical Trials register) were used to identify phase 3 trials of emicizumab. Matching adjusted indirect comparison was used to compare annualized bleed rates (ABR) (including any bleed, any treated bleeds, joint, and spontaneous). Matching characteristics included: age, race, previous regimen, and target joints prior to study enrolment. The relative efficacy of efanesoctocog alfa versus emicizumab was summarized as incidence rate ratios with 95% confidence intervals.

Results: The SLR identified one phase 3 trial for emicizumab (HAVEN-3). Individual patient-level data from Arm A (once-weekly prophylaxis, n=133) of XTEND-1 study was matched to published aggregate data from Arm D (every week prophylaxis, n=63) of HAVEN-3 study. After matching, the patient population was well-balanced between the two treatments, and the effective sample size was 64% of the initial sample size. Efanesoctocog alfa (Arm A) was associated with significantly lower ABR for any bleeding, any treated bleeding, and joint treated bleeding compared with emicizumab Q1W (Arm D) (Figure 1). The incidence of spontaneous ABR was lower with efanesoctocog alfa versus emicizumab, however, the result was statistically non-significant (Figure 1).

Conclusion(s): Prophylaxis with once weekly efanesoctocog alfa in patients with severe hemophilia A significantly decreased the rate of any bleeding, any treated bleeding, and joint bleeding compared with emicizumab.
Funding disclosures: This study was funded by Sanofi and Sobi.