Michael Makris: 3 PTP Haemophilia A in Japan Have Developed FVIII Inhibitors Following Treatment with Efanesoctocog Alfa
Michael Makris, Emeritus Professor of Haemostasis and Thrombosis at the University of Sheffield, shared on LinkedIn:
“Three Previously Treated Haemophilia A Patients (PTPs) in Japan have developed FVIII inhibitors following treatment with efanesoctocog alfa (Altuviiio/Altuvoct). One had severe haemophilia, and the other two had moderate and mild disease. Only 38 patients were exposed to efanesoctocog alfa in the centres these 3 patients were reported from.
This is a very much higher rate than expected, and the reasons are unclear.
Was it chance? We will know very soon, as this drug is now used extensively in PTP haemophilia A patients around the world.”
Title: The First Three Japanese Haemophilia A Patients in Whom Factor VIII Inhibitors Were Observed During Prophylactic Treatment With Efanesoctocog Alfa
Authors: Tazuko Tokugawa, Akihiro Sawada, Satoshi Higasa, Mariko Asai, Hideyuki Nakazawa, Azusa Nagao, Tomoko Yamaguchi, Yushi Chikasawa, Masato Bingo, Takeshi Hagiwara, Katsuyuki Fukutake

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