Stability of GR63178A, a novel pentacyclic pyrroloquinone anticancer compound, in aqueous solutions and biological...

The effect of temperature, pH, light, drug concentration and aeration on the stability of aqueous solutions of GR63178A, a novel anticancer compound, has been investigated. The effect of light upon the stability of GR63178A in a clinical infusion system and in biological fluids, has also been investigated. A high performance liquid chromatographic assay was used to separate the parent compound from a number of degradation products. Data presented here demonstrate that GR63178A is stable in aqueous solutions at normal ambient temperatures in neutral or alkaline pH ranges. The compound is unstable when exposed to light (t1/2 3.2-233 min) and shows an inverse relationship between concentration and rate of degradation. The drug is also unstable under acidic conditions, but shows a more limited spectrum of degradation products than those arising from photolysis.