AAPS PharmSci 360 2026: High-Loaded ASD

At the AAPS PharmSci 360 event in New Orleans, which occurred from October 25-28, 2026, PharmTech sat down with Nitin Kumar Swarnakar, PhD, global application lab manager at BASF Corporation, to learn about the challenges with formulation and characterization for amorphous solid dispersions (ASDs). According to Swarnakar, dissolution failure remains the main indicator of ASD performance. Conventional methods, such as differential scanning calorimetry (DSC) and X-ray diffraction (XRD), cannot fully explain dissolution behavior because they do not detect the microstructures that lead to crystallinity. His team has found Raman spectroscopy useful for understanding these microstructures and linking them to dissolution.

Designing an ASD starts with understanding the API. Some drugs are strongly crystalline, “brick dust” compounds, while others are better suited to lipid-based approaches, Swarnakar explains. The relationship between a drug’s Tg and melting point helps determine whether an ASD is a viable option.

On polymer selection, copovidone is among the most widely used excipients, while some companies are exploring low-molecular-weight povidone to bring ASDs to market while working around patented technologies. Swarnakar stresses that 2 factors matter most: a polymer Tg at least 50 °C above room temperature, and functional groups on the API and polymer that interact to lock the drug into the dispersion. The key difference between the 2 polymers is hygroscopicity. Povidone absorbs more moisture than copovidone, so moisture must be tightly controlled; otherwise, the polymer’s Tg drops and ASD stability suffers, he explains.

Swarnakar describes Raman spectroscopy as valuable but qualitative, reflecting the sampled area rather than bulk properties, which underscores the need for additional characterization tools. Because it is nondestructive and easy to use, Raman could serve as a process analytical tool to monitor crystallinity across the entire extrudate during hot-melt extrusion.

About the Speaker

Nitin Kumar Swarnakar, PhD, is global application lab manager at BASF in Tarrytown, New York. He holds BPharm, MPharm, and PhD degrees in pharmaceutical science, has worked with generic and innovator drug companies, and has been with BASF for 7 and a half years.