Riociguat, a
potent
vasodilator that is the first in a new class of drugs,
has been approved by the Food and Drug Administration for
treating
two types of pulmonary hypertension in adults.
The
drug, which will be marketed as Adempas, was approved Oct. 8 to treat:
1-chronic
thromboembolic pulmonary hypertension (CTEPH)
and,
2- pulmonary arterial
hypertension (PAH),.
Orally
administered in tablet form, riociguat is
a soluble
guanylate cyclase (sGC) stimulator, the first drug in this class
to be approved for pulmonary hypertension. It is also "the
first drug of any class to be shown to be effective for patients
with CTEPH
Riociguat is
a pregnancy category X drug and is available to women only through a Risk
Evaluation and Mitigation Strategy (REMS) program.
The approved
indications for
the drug, which will be marketed by Bayer HealthCare Pharmaceuticals,
are for:
1-persistent/recurrent
CTEPH (WHO group 4)
"after surgical treatment or inoperable CTEPH to improve exercise
capacity and WHO functional class"
or PAH (WHO group 1)
"to
improve exercise capacity, improve WHO
functional class, and to delay clinical worsening."
Approval
was based on the results of two international studies that found treatment
resulted in significant improvements over placebo in the 6 minute walk test.
In
the study of 380 patients with PAH, the change from baseline in the
6-minute walk test at 12 weeks improved by a mean of 30 m among those treated
with riociguat,
vs. a mean drop of 6 m in the placebo group.
The WHO functional class
improved in 21% of those on riociguat,
compared with 14% in the placebo group, deteriorating in 4% and 14%,
respectively.
In
the study of 261 patients with CTEPH, the change from
baseline in the 6-minute walk test at 16 weeks improved by a mean of 39 m among
treated patients vs. a mean 6 m reduction in the placebo group at 16 weeks. WHO
functional class improved in 33% of those on riociguat and 15% of those on
placebo, deteriorating in 5% and 7%, respectively.
The
two studies were published in the July 25 issue of the New England Journal
of Medicine (2013;369:330-40; 2013;369:319-29).
