Physicochemical Properties and Dose Selection

Physicochemical Property Testing

  • Solubility Assessment (bio-buffers and formulation excipients)
  • Dissolution Testing
  • Chemical Stability
  • LogD Assessment

Dose Vehicle Development & Evaluation:

  • Excipient Selection
    • API – Compatibility
    • Vehicle – Suitability
  • Stability (dose vehicle)
  • Artificial Fluids Interactions
    • Simulated (gastric and intestinal fluids)
    • Phosphate-buffered Saline
    • Hanks’ buffer with and without bovine serum albumin
  • In Vivo Performance Characterization

Example: Steroid danazol administered orally to rats

Physicochemical PropertiesDanazol is a derivative of the synthetic steroid ethisterone, a modified testosterone. Before becoming available as a generic drug, danazol was marketed as Danocrine in the United States. It was approved by the FDA as the first drug to specifically treat endometriosis in the early 1970s. Labrafil likely forms micelles when mixing with aqueous physiological fluids. This keeps the danazol in solution as opposed to precipitating out as probably occurs with PEG solution.

In Vivo Evaluation

We offer various surgically ported animal models to help with formulation assessment in addition to the standard rodent, canine and non-human primate models for oral and intravenous dosing. These include rats, dogs, and mini-pigs fitted with intestinal cannulas implanted at various sites for dosing solutions or suspensions, as well as dogs fitted with duodenal fistulas for dosing solids, semi-solids, capsules, and tablets directly into the duodenum. Several of these animal models are available routinely and other custom models can be prepared in line with customer needs.

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