Rivaroxaban for the treatment of deep vein thrombosis and ...

stated that xxxx of patients discontinued treatment after an EC bleed, but used xxx in the economic
model.
Despite these limitations, sensitivity analyses conducted by the manufacturer showed that a variation
in the discontinuation rate had a limited impact on the results. 1
Probability of VTE recurrences after treatment cessation (at the end of the intended treatment
duration)
The manufacturer carried out a systematic review of the literature to identify trial-based and
observational literature providing evidence on rates of recurrent VTE in patient populations with
index DVTs, PEs or VTEs. 40 16,795 potentially relevant studies were identified in Medline, Embase
and Cochrane Library literature databases, and 129 studies were included. Of those, the manufacturer
reported that 16 publications had a long follow-up period, and 13 were believed to be relevant by the
manufacturer;
- “the Prandoni cohort” (terminology used by the manufacturer) has been described in three
publications, with data from the most recent publication used. 8 This comprised a cohort of
1,626 patients with clinically symptomatic proximal DVT and/or PE from centres based at the
University of Padua, Italy, who were initially treated with anticoagulation.
- “the Vienna cohort” (terminology used by the manufacturer) (Eichinger 2010 9 ) has been
described in ten publications, with data from the most recent publication used. 9 This
comprised a cohort of 929 patients with a first VTE from four thrombosis centres in Vienna
and Austria, who had completed at least 3 months of anticoagulation treatment.
The manufacturer’s economic model used data from the Prandoni cohort 8 in the basecase analysis as
this included more patients and estimated the three month probability of VTE recurrence to be 1.26%
(95% CI 1.09% to 1.46%) using data at 10 years only. The manufacturer also assumed that 19.2% of
VTEs were PEs after cessation of treatment using data from Prandoni et al (1996). 6 Sensitivity
analyses were conducted by the manufacturer varying the rates within the 95% CI and showed a
minimal impact on the results.
The ERG finds the approach used by the manufacturer to identify evidence on the rate of long term
VTE recurrences generally satisfactory and transparent. Note that the ERG did not attempt to
reproduce the systematic review presented by the manufacturer due to time and resource constraints.
The manufacturer used data from the Prandoni cohort, 8 however, this is an old cohort, and might not
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