Sounds like a good reason for a clinical trial?
These authors performed a randomized open-label noninferiority trial comparing apixaban to daltiparin in over 1000 patients in 119 centres in Europe, Israel and the USA.
They excluded patients with any CNS malignancy, leukemia, basal and squamous cell skin cancers, or if they were high risk of bleeding.
The primary outcome was recurrent DVT/PE during the trial period.
Recurrent DVT/PE occurred in 5.6% of the apixaban group and 7.9% of the daltiparin group. This met their non-inferiority margin but was not quite enough to claim superiority (p=0.09). Major bleeding was the same in both groups.
Maybe…there was a trend towards more “clinically relevant” non-major bleeding with apixaban at 9% compared to 6% . This should lead to some caution as they already excluded those with high risk of bleeding.
Although the authors claim this was an “investigator-initiated” trial, it was funded by a “Bristol-Myers Sqibb-Pfizer Alliance.” In addition, there is an impressive list of author conflicts of interest- lecture & consulting fees, grant money, travel expenses, advisory board fees, etc. etc.
Either way, this trial published in the NEJM will be considered “high quality evidence” and will change the guidelines. Hopefully it's right.
Covering: Agnelli G, Becattini C, Meyer G, et al. Apixaban for the Treatment of Venous ThromboemolismAssociated with Cancer. N Engl J Med 2020;382:1599-607. [Link to article]
Dr Brian Doyle is an emergency physician originally from the United States but now very much calls Tasmania his home. Unfortunately, it will now be a bit more difficult to deport him from the country as he passed his Australian citizenship test a few years ago. (He was able to answer that Phar Lap won the Melbourne rather than the Davis Cup). His main interests are mostly the clinical aspects of emergency medicine but also in education, ultrasound and critical appraisal of the literature. He spends much of his time annoying people to help out with conferences.