Preclinical Formulation Screening

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Preclinical Formulation Screening

Study Purpose

In the drug discovery process, formulation plays a crucial role in assessing the biological characteristics of molecules. Increasing the exposure of the test compound in studies in vivo is one of the main goals of early in vivo experiments [16, 17]. Choosing a suitable preclinical formulation not only optimizes in vivo PK exposure but also promotes the optimization, selection, and development evaluation of compounds to provide data support for the design and development of clinical formulations [18]. For the test compounds in the early screening stage, the unsatisfactory physical and chemical properties, the insufficient compound amount, and the tight time are commonly encountered. In response to these challenges, the DMPK of WuXi AppTec established a team for preclinical formulation screening for PK studies, pharmacodynamic and toxicological studies. The team has more than ten years of experience and can perform rapid formulation screening and preparation services for large and small animal experiments. They also provide more than nearly 1,000 arms of formulations for preclinical in vivo experiments every week. They can use limited (milligram) compounds to offer a suitable formulation for preclinical animal experiments within 24 hours.

Study Methods

The formulation team can select vehicles that meet the requirements of the PK study within one working day. In formulation screening, solubilization technology (such as pH adjustment and cosolvent) is a commonly used technical means. For some poorly soluble compounds, a cosolvent plus surfactant or complexing agent plus pH adjustment are typically used in combination. In addition, the DMPK formulation team can customize the formulation screening strategy according to differentiated project needs.

Strategy [19]
Particle size reduction
Amorphous solid dispersion
Lipid-Based Formulation



Siri T3 for The pKa Measurement


Small Animal Implantable Osmotic Pump

Malvern-3000 Particle Size Tester

Polarized Light Microscope

Retsch Wet Ball Mill

Covaris®E200x ULtra Ultrasonic Disperser

Rodents Capsule


Retsch Ball Mill

Experimental Flow

The formulation team provides formulation screening and formulation services for pharmacokinetic studies from the screening stage to the IND application stage. It provides formulation screening services for pharmacodynamic tests and preclinical toxicological experiments. The team can select suitable excipients to dissolve the compound to tackle the solubility issue according to the physical and chemical properties of each specific drug substance (such as dissociation constant pKa, lipophilicity, aqueous solubility). The most appropriate formulation for a drug substance is selected by in vitro solubility assessment, homogeneity, and particle size analysis. Further screening is performed from eligible candidates to ensure the formulation with the best in vivo bioavailability or experimental objectives is achieved.

Experimental Flow for Preclinical Formulation Screening
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