CARDIOVASCULAR JOURNAL OF AFRICA • Vol 21, No 3, May/June 2010
174
AFRICA
Dabigatran launch
continued from p.173
In the published literature, direct
comparisons of rivaroxaban and dabigat-
ran are not possible. However, in inter-
preting anti-coagulant data and compar-
ing these drugs to enoxaparin as far
as safety is concerned, it is clear that
rivaroxaban with its superior efficacy
carries a consistently higher bleeding risk.
This view is supported by independent
evaluations undertaken by the FDA and
those done for the UK standard, NICE.
‘The NICE technology guideline in fact
comments that with regard to efficacy,
the two agents are similar, but there is a
tendency to increased bleeding with rivar-
oxaban’, Prof Frostick said.
The availability of two doses of dabigat-
ran is useful when dealing with more frag-
ile patients such as the elderly (
>
75 years)
and those with moderate renal insuffi-
ciency. ‘In the period of real-life clinical
usage of these new entities, we need to do
our own post-marketing surveys and we
should not be complacent about any new
clinical agents’, Prof Frostick concluded.
The panel of South African experts
added to the presentation with their
experience of using dabigatran in the
clinical trials locally, which increased
patient numbers significantly in both the
RE-MODEL and RE-NOVATE trials.
‘Mobility in the older patient under-
going surgery is very important and we
should understand the need for anti-coag-
ulation in these patients for an extended
period of time’, Prof Barry Jacobson,
head of haematology at the Witwatersrand
University pointed out. ‘The clinician
should watch out for non-steroidal anti-
inflammatory usage, and protease inhibi-
tors for HIV treatment can also compli-
cate the expected anti-coagulant action of
dabigatran’, he warned.
With regard to reversing the effects
of dabigatran when required, activated
charcoal and recombinant factor VIIA are
useful, while in an emergency situation,
the patient can be dialysed. The advantag-
es of an oral medication such as dabigat-
ran cannot be ignored as patients are
now sent home very early after surgery,
normally within three to five days.
J Aalbers, Special Assignments Editor
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