Mitchel L. Zoler/IMNG Medical Media
Dr. Sanjay Kaul
Because a legitimate question regarding reliability of INR measurements has been raised, it would seem prudent to reassess safety and efficacy data, said Dr. Kaul, professor of medicine at the University of California, Los Angeles, in an interview. “Ideally, this should be done by an independent party as was done for the RECORD trial of rosiglitazone by Duke investigators who were not involved in the clinical trial. Personally, I am not sure if the benefit-risk balance will be materially altered. Potential overestimation of safety of rivaroxaban related to spuriously low INR with warfarin will likely be counterbalanced by underestimation of efficacy.” If there are data from INR assessments performed centrally in a core lab, independent investigators could use those to reassess efficacy and safety, he continued. “At least the investigators should use the core lab INR to verify their assumptions in the research letter published in NEJM that conditions of recall were truly associated with low INR values. Otherwise, their results are open to question.”
Of note, Dr. Robert M. Califf, who was a ROCKET-AF study cochair and is now FDA Deputy Commissioner for Medical Products and Tobacco, was not involved in the analysis. Dr. Califf is awaiting confirmation from Congress on his nomination to head the FDA.
Dr. Patel received support from Johnson & Johnson, Bayer, and Janssen in relation to ROCKET-AF, and from eight other drug and device companies, as well as the National Heart, Lung, and Blood Institute. Disclosures for all the investigators are at nejm.org. Dr. Kaul has stock interest in J&J, which sponsored ROCKET-AF, and serves as a consultant to Boehringer Ingelheim and Bristol-Myers Squibb.