To the Editor:

We read with interest the report by Yocum and colleagues of the efficacy and safety of tacrolimus for the management of rheumatoid arthritis (RA) (1). Prior to randomization, the investigators determined whether patients could not tolerate or had disease that was resistant to disease-modifying antirheumatic drugs (DMARDs). Although they state that lack of efficacy was rigorously predefined, no mention was made of which DMARD was used or what dosage would define failure/intolerance.

The omitted information is important, because we have noticed investigators deeming patients “DMARD failure” before the standard maximal recommended dosages of the DMARD have been instituted. Using methotrexate (MTX) as an example, the reader could easily assume that patients in the study by Yocum et al were considered MTX intolerant (if MTX was used) at a dosage of approximately 10–15 mg/week, because several other investigators have done this (2–6), even though the American College of Rheumatology (ACR) considers the maximal standard maintenance dosage to be as high as 20 mg/week (7). We admit that keeping MTX dosages below the maximal standard maintenance dosages set forth by the ACR should make a competitor drug relatively more effective. Regarding the DMARD used, readers may anticipate that the response to a biologic DMARD may be different from that to medications such as hydroxychloroquine or sulfasalazine.

Failure to report the meaningful information regarding individual DMARDs used or the DMARD dosages administered before patients are considered “DMARD intolerant” or “DMARD failures” diminishes the clinical utility of the study for the reader.

MAJ (ret) Christopher T. Parker MC, DO*, MAJ Thomas Rennie MC, MD†, * Austin Diagnostic Center Austin, TX, † Brooke Army Medical Center San Antonio, TX.