Celator Pharmaceuticals, a subsidiary of Jazz Pharmaceuticals, is a pharmaceutical company developing new and more effective therapies to treat cancer. CombiPlex®,the company's proprietary drug ratio technology platform, represents a novel approach that identifies molar ratios of drugs that will deliver a synergistic benefit, and locks the desired ratio in a nano-scale drug delivery vehicle that maintains the ratio in patients with the goal of improving clinical outcomes. The company pipeline includes two clinical stage products, CPX-351 (a liposomal formulation of cytarabine:daunorubicin) for the treatment of acute myeloid leukemia and CPX-1 (a liposomal formulation of irinotecan:floxuridine) for the treatment of colorectal cancer; and preclinical stage product candidates, including CPX-571 (a liposomal formulation of irinotecan:cisplatin), and CPX-8, a hydrophobic docetaxel prodrug nanoparticle (HDPN) formulation being studied by the National Cancer Institute's Nanotechnology Characterization Laboratory.

On May 31, 2016, Jazz Pharmaceuticals and Celator Pharmaceuticals announced an agreement for Jazz Pharmaceuticals to acquire Celator for $30.25 per share in cash, or approximately $1.5 billion.