Regulatory forum opinion piece: Clarification and simplification of the pathology peer review documentation process.

The transparency and documentation of the peer review process have been discussed recently. Our position is that transparency is best achieved when peer review is a collaborative process, in which both parties are open-minded but both also realize that the study pathologist retains complete control over the findings (raw data) and over the content of the pathology report. For these reasons, we believe that histopathology raw data should be defined as the observations made by the study pathologist (printed and/or electronic formats) rather than as the tissue slides recommended by the Organisation for Economic Co-operation and Development (OECD). Also, because the study pathologist retains control over the histopathology raw data, any notes or tabulations of findings by the study pathologist and peer review pathologist during the peer review are interim notes and should not be included as an appendix to the pathology report though they may be retained if desired, as currently recommended. Because the histopathology raw data have not been created until completion of the peer review, the performance of a peer review should be documented in the study report, as currently recommended, but that it not be a GLP-compliant process.

Nasal turbinate enlargement due to cartilage and bone proliferation: a normal developmental finding in young ferrets.

Toxicity studies of intranasally administered, live attenuated influenza virus vaccine candidates conducted in male and female ferrets led to the microscopic observation of individual differences in the size of nasal turbinates, especially in the dorsal aspect of the nasal cavity. The association of these enlarged turbinates with acute to subacute inflammation, which is sometimes common in ferrets given live attenuated influenza virus vaccine candidates, led to this detailed microscopic evaluation of turbinate enlargement (cartilaginous and osseous thickening, or COT) in control animals dosed intranasally with saline. Results of this evaluation led to the conclusion that COT is a normal developmental feature of growing ferrets, irrespective of inflammation in nasal tissues or inflammatory exudate in the nasal cavity.