Press Release

Sanofi provides update on regulatory review in the EU
for Rezurock to treat chronic graft-vs-host disease

Paris, October 17, 2025. The European Medicines Agency’s Committee for Medicinal
Products for Human Use (CHMP) has issued a negative opinion on the marketing
authorisation application for Rezurock (belumosudil) for the third-line treatment of adults
and pediatric patients with chronic graft-versus-host disease (cGVHD). Sanofi will seek a
re-examination of the CHMP opinion.

cGVHD is a life-threatening complication that devastates the lives of up to 50% of
patients who undergo a stem cell transplant. cGVHD is considered one of the main
causes of morbidity and late non-relapse mortality after stem cell transplant.

“We are disappointed by the negative CHMP opinion for Rezurock in the EU and
remain committed to serving the transplant patient community,” said Olivier
Charmeil, Executive Vice President, General Medicines at Sanofi. “Sanofi is
confident in the body of clinical and real-world evidence that underscores
Rezurock’s consistent efficacy and well-established safety profile for treating
third-line chronic graft-versus-host disease. We will continue to work closely with
the European Medicines Agency with the aim of bringing this treatment to
patients in the EU who are waiting.”

Rezurock is supported by safety and efficacy results from several clinical studies and
real-world evidence. This includes the randomized, multicenter ROCKstar phase 2 study,
that demonstrates consistent efficacy and tolerability for patients living with cGVHD after
stem cell transplant as well as durable clinical responses over a period of three years.

Rezurock is currently approved in 20 countries, including the US, UK and Canada for the
treatment of patients 12 years and older with cGVHD after failure of at least two prior
lines of systemic therapy and in China after failure of one prior line of systemic therapy.

More than 17,000 patients living with cGVHD worldwide have been prescribed Rezurock
since its first approval in the US in July 2021.

About Rezurock
Rezurock (belumosudil) is a first-in-class selective ROCK2 (Rho-associated coiled-coil
kinase 2) inhibitor (ROCK2i).

Sanofi is committed to investigating the benefits of Rezurock in other age groups and
indications, including through ongoing studies for pediatric patients with cGVHD from
one year old who have been treated with at least two prior lines of systemic therapy and
for patients with chronic lung allograft dysfunction.

About chronic graft-versus-host disease
GVHD is a complication that can occur following stem cell transplant (or allogeneic
hematopoietic stem cell transplant) where the donor’s (graft) cells attack the host’s cells,
leading to inflammation and fibrosis (scarring or thickening) that can damage multiple
tissues and organs. Chronic GVHD devastates the lives of up to 50% of patients who
undergo an allogeneic hematopoietic stem cell transplant. GVHD is considered one of the
main causes of morbidity and late non-relapse mortality after stem cell transplant. The
consequences are far-reaching, both in terms of the burden it can place on the
individual’s physical and emotional well-being, as well as the broader socio-economic
impact.


About Sanofi
Sanofi is an R&D driven, AI-powered biopharma company committed to improving people’s
lives and delivering compelling growth. We apply our deep understanding of the immune
system to invent medicines and vaccines that treat and protect millions of people around
the world, with an innovative pipeline that could benefit millions more. Our team is guided
by one purpose: we chase the miracles of science to improve people’s lives; this inspires
us to drive progress and deliver positive impact for our people and the communities we
serve, by addressing the most urgent healthcare, environmental, and societal challenges
of our time.
Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY

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