They were presented at ECRIMS. See poster here

In these situations, especially if live CBA is not available for follow-up testing in patients with high suspicion for MOGAD or AQP4+ NMOSD, clinical and imaging phenotypic characteristics need to be relied on more heavily to help guide appropriate management.

We must recognize though that fixed CBAs may be the only assays readily accessible, especially in resource-limited settings.

These results support that using exclusively fixed CBAs may miss many cases resulting in misdiagnosis and consequently suboptimal treatment, but also has significant implications for characterizing "double-seronegative" NMOSD.

Live CBA had markedly better sensitivity, especially for MOG-IgG testing, with very good specificity for both live and fixed CBA (notably specificity was 100% for AQP4-IgG by both assays).

A multi-center, randomized-controlled, open-label, rater-blinded, pragmatic trial “Treatment of Inflammatory Myelitis and Optic Neuritis with Early vs Rescue Plasma Exchange” that is planned to commence in the United States in 2025.

Regardless though, a randomized controlled clinical trial is needed to further inform the use and timing of PLEX for treatment of severe demyelinating attacks. This is why we are pursuing (together with co-PI
Dr. John Chen from Mayo), the TIMELY-PLEX trial:

Performing additional analyses, including a formal comparison of 1st-line PLEX recipients vs those who received only corticosteroids, accounting/matching for relevant variable such as demographics, attack severity etc can help provide further insight into these findings.

So unless we think that PLEX actually worsens clinical outcomes (which seems unlikely), it should be fairly clear that this is likely driven by selection bias.

Notably, in this study patients treated with only corticosteroids for their attacks had BETTER disability than those who received PLEX at the last follow-up, despite similar demographics and clinical characteristics.

This is a huge selection bias that is present in all retrospective studies of PLEX in NMOSD and MOGAD, since the analysis is restricted only to those who received PLEX.

PLEX is not done as a 2nd or 3rd-line therapy randomly, but because patients did not significantly improve or even worsened after 1st line therapy. Conversely, many of those who received PLEX as a first-line therapy may have improved with just corticosteroids.