Most DVT’s and PE’s in patients with cancer are treated with low molecular weight heparin. As if the malignancy was not enough, now they will get painful daily injections often for the rest of their life.
Seems cruel… why not just use a DOAC?
In turns out, there was no good evidence that they could be used in this population and there was some concern about increased bleeding.
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.
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.
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]