Reduced WBC and lymphocytes; lymphoid depletion in spleen, thymus, lymph nodes and GALT
“The target organs were identified as lymphoid organs in both species, with major study findings including reduced circulating white blood cells and lymphocytes and decreased lymphocytes/cellularity in various lymphoid tissues (including spleen, thymus, lymph nodes, and gut-associated lymphoid tissue).”
✓ VerifiedFDA multi-discipline review, p. 50Source ↗
Biodistribution & persistence
Excreted in rat milk; milk/plasma ratios ~7 to 20 over 8 hours
“Milk/plasma concentration ratios were approximately 7, 13, 19, and 20 at 1 hr, 2 hr, 4 hr, and 8 hr postdose, respectively.”
✓ VerifiedFDA multi-discipline review, p. 48Source ↗
Modality-specific risk
Exaggerated JAK pharmacology: lymphoid organ toxicity with reduced white cells and lymphocytes
“The major safety signals identified in these studies were consistent with deuruxolitinib’s pharmacological activity. The target organs were identified as lymphoid organs in both species, with major study findings including reduced circulating white blood cells and lymphocytes”
✓ VerifiedFDA multi-discipline review, p. 45Source ↗
Anti-drug antibodies: animals
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Anti-drug antibodies: patients
Not assessed (small molecule, not expected to be immunogenic)
“Deuruxolitinib is a small molecule that is not expected to be associated with immunogenicity. Therefore, the Applicant did not assess the potential for antibody formation.”
✓ VerifiedFDA multi-discipline review, p. 145Source ↗