Making Sense of Discrepant Data

Last month my column was dedicated to the controversy surrounding conflicting data about XMRV in samples from CFS patients – one set from researchers at the Centers for Disease Control & Prevention (CDC) and another set from a joint team of researchers at the Food and Drug Administration (FDA) and National Institutes of Health (NIH). All three agencies are part of the Department of Health and Human Services (HHS). It’s rare for agencies to be at odds, although it has certainly happened before – even in CFS. For instance, NIH does not recommend application of the CDC’s 2005 “empiric” case definition for CFS research it funds, nor does it quote the higher prevalence figures that this broader definition generates. So, it’s not impossible that conflicting findings would find some way to peacefully coexist within the HHS framework. And it seems inevitable that will be the case with XMRV data, at least for a period of time.

The now-famous-although-not-yet-published study from collaborators led by Dr. Shyh-Ching Lo at FDA and Dr. Harvey Alter at NIH is at press and will be published in the Proceedings of the National Academy of Sciences (PNAS). No one seems willing to put a date on publication since that is now the journal’s decision alone. (PNAS is published weekly, on Tuesdays.) I spoke with individuals close to the Lo-Alter study at the July 26 meeting of the FDA’s Blood Products Advisory Committee (BPAC) and all were eager for attention to move from the controversy to evaluation of the published data. They seemed more hampered by the spotlight’s glare than by political resistance to their findings, but it’s likely we’ll never know how all the events unfolded between the leak of Dr. Alter’s Zagreb presentation and the final date of publication.

Dr. Anthony Komaroff stated a few days ago, “The publication of one paper will not and should not end all controversy. Science proceeds in small steps, and scientific judgments are made and should be made on the basis of a body of work from multiple investigators.” There have been about 55 studies published on XMRV since it was discovered in 2006; two-thirds of them in this year (2010), and five in the past week alone. Scientific understanding of XMRV as an agent and possible pathogen is rapidly evolving.

A month from now, NIH will convene the First International XMRV Workshop. A diverse cross-section of those who have published in the area are represented on either the Organizing Committee or the Scientific Committee. More than 40 abstracts were submitted on a range of topics, and it’s likely that within that array, not all the findings will fit neatly into a cohesive, conclusive model. There are bound to be rough edges that only more research will smooth.

Work on the XMRV blood safety study continues, with Phase I complete and analysis of clinical panels of samples continuing by six labs whose assay methods were all sensitive enough to detect at least 136 proviral copies per milliliter of whole blood. The FDA is in the process of making the XMRV-related presentations from the BPAC meeting available on its website. We’ll provide a link on our XMRV resource page as soon as they’re posted. We’re also pleased to host Dr. Louis Katz for an Aug. 12 webinar on XMRV & Blood Safety, during which he will give an updated on the blood safety studies. Dr. Katz is a top expert on infusion medicine and is a widely respected infectious diseases physician.

All of the public events that we can catalog on our XMRV resource page take place against a backdrop of informal, confidential and/or privileged communications between collaborators, committee members, funders and competitors. It’s hard to be patient when firm answers have eluded those affected by CFS for so long, but we take some comfort in knowing there are many catalysts acting to accelerate the momentum – even if some that catalytic action occurs behind the scenes.

Kim McCleary
President & CEO
August 6, 2010

August 6, 2010