Correction fixes unit label in feline P-glycoprotein study: full analysis
A new correction in Frontiers in Veterinary Science updates a detail in a 2025 feline pharmacology paper without changing the paper’s core message. The May 22, 2026 notice says Table 2 in “Assessment of clinically relevant drugs as feline P-glycoprotein substrates” used the wrong unit abbreviation in the “Concentration Range” column: “MM” was printed instead of “μM.” The corrected table has now been posted, and the journal states that the original article has been updated. (frontiersin.org)
The underlying study matters because it focused on feline P-glycoprotein, or P-gp, a drug transporter that can influence brain penetration, biliary excretion, and the clinical significance of drug-drug interactions. In the original paper, Mealey and Burke evaluated clinically relevant drugs for cats rather than relying only on classic human P-gp probe drugs, aiming to make the findings more useful in real-world feline practice. The paper also sits within a broader body of work showing that some cats have an MDR1 variant associated with P-gp deficiency, and that P-gp dysfunction can also arise through drug interactions, not just inherited genetics. (frontiersin.org)
The corrected table itself remains clinically informative. In the original article, drugs categorized as strong feline P-gp substrates included cyclosporine, emodepside, eprinomectin, ivermectin, loperamide, selamectin, vinblastine, and vincristine. Cisapride and methylprednisolone were classified as moderate substrates, amlodipine and capromorelin as weak substrates, and cefovecin, doxycycline, ronidazole, and cisplatin as non-substrates in this assay system. The concentration ranges tested were intended to reflect plasma concentrations reported on labels or in pharmacokinetic studies in cats, or in dogs when feline data were unavailable. (frontiersin.org)
That’s why a unit correction matters, even though it may look minor. A mislabeled concentration column can distort how readers judge assay relevance, potency, and translational value. In this case, the issue appears limited to presentation, not the data themselves: the correction notice points specifically to the table header and does not report revised interpretations, changed ratios, or altered conclusions. (frontiersin.org)
The paper’s broader clinical framing is also worth noting. The authors wrote that these substrate designations are useful when weighing risks and benefits in P-gp-deficient patients and when considering dose reductions for substrate drugs in those patients. They also noted that their results aligned with existing in vivo or presumed substrate status for several drugs already associated with feline or comparative P-gp concerns, including ivermectin and eprinomectin. (frontiersin.org)
Why it matters: For veterinarians, pharmacists, and toxicology-minded clinicians, this correction is a reminder that even small publishing errors can affect interpretation of pharmacology tables that may later inform prescribing, compounding, or adverse event review. The practical takeaway is unchanged: feline P-gp substrate status is relevant when considering neurotoxicity risk, blood-brain barrier exposure, and potential interaction effects, especially in cats with suspected transporter deficiency or in patients receiving multiple drugs. Inference: because several drugs in the study are commonly encountered in feline medicine, this table is likely to be used as a reference point beyond the paper itself, which raises the importance of getting units exactly right. (frontiersin.org)
No independent expert reaction to this specific correction was readily visible in the sources reviewed, which is not unusual for a narrow erratum. Still, the surrounding literature from Mealey and others has consistently emphasized that P-gp-mediated interactions can have clinically important consequences in veterinary patients, especially where substrate drugs and transporter impairment overlap. (cir.nii.ac.jp)
What to watch: The next step is less about this correction itself and more about application: whether future feline pharmacology studies, clinical decision tools, or consensus guidance build on these substrate classifications, and whether additional work clarifies how in vitro feline P-gp findings translate to bedside dosing and safety decisions. (frontiersin.org)