Sorafenib

Excerpt

A 64-year-old man with metastatic renal cancer received oral sorafenib 400mg twice daily for 11 months. After 1 month he developed hypophosphataemia. His low serum phosphorous levels persisted for 2 months; this was accompanied by decreased serum calcium, urinary calcium, phosphate, vitamin D, serum fibroblast growth factor 23 and serum C-telopeptide of type I collagen [CTX]. His serum parathyroid hormone increased. He received colecalciferol and his serum phosphate normalised over 2 months, while his other laboratory test results improved.Author Comment“[D]rug-induced hypophosphatemia in this patient was sustained by a low intestinal phosphate absorption and/or low bone phosphate release... Sorafenib inhibited the osteoclast activity as documented by the decrease of serum CTX.” …