[Quiny11]

1% phenoxyethanol?

[Quiny11]

15% azelaic acid prescriptions in the US are mostly suspensions of micronized azelaic acid (e.g., Cosroma)-this requires a basic thickener with yield value to prevent sedimentation (e.g., carbomer) and chaotropic agents like ~10% propanediol and some surfactant. You may be able to achieve a ~10% level of dissolution using very high levels of ethoxydiglycol and other glycols-your aim would be to create an almost anhydrous formula. Azeloyl glycinate derivatives would also allow high dissolution, but you would have to keep the pH above 7 probably to keep it from precipitating.