US Patent 8,932,715 covers the use of precipitation stabilising additives for making powders used in therapeutic proteins, including mAbs. The technology turns delicate biopharmaceuticals, which are unstable in water-based solutions, into stable dry microparticles while keeping their bioactivity.
It allows drug makers to safely store biologics as bulk dry powders, preserving APIs for more than seven years, or as high-concentration mAb solutions for subcutaneous injection.
The precipitation process is a “disruptive technology” to more commonly used lyophilisation, the company’s R&D Director said. Compared to freeze-drying, XstalBio’s process “offers advantages of speed, cost and dose-flexibility and it produces humidity- and temperature-stable powders that are much easier to handle than spray dried particles,” said Barry Moore.
The patented additives prevent damage to drugs’ protein structure when they are converted into a dry powder and allow the dried formulation to be dissolved to form a stable high-concentration solution.
The company is developing the process for GMP. Moore told BioPharma-Reporter.com XstalBio will seek an M&A into a larger organisation “because this will provide the most rapid route for taking the technologies to the market and maximise the commercial benefits provided by the patent portfolio.”
Patient trends
XstalBio’s R&D Director told BIoPharma-Reporter.com changes in patient dosing require pharma companies to rethink drug stability.
In the past, most biologics were given to patients in hospital through intravenous infusion – meaning a large volume is given slowly via a drip. “In such dilute solutions, mAbs are typically fairly stable and many different additives can be used.
“Nowadays, to increase patient convenience and compliance and to reduce cost there is increasing demand to dose the patient away from a hospital setting. This requires the same amount of protein to be provided in much smaller volume so it can be administered to the patient in a single injection or from a portable infusion device.”
A smaller volume means higher concentration, so these proteins are typically much less stable, and their shelf-life in solution is very short, said Moore.
“In addition it becomes increasingly difficult to actually manufacture protein solutions using conventional routes, as the final concentration is increased. There is therefore a demand for new processing methods that can allow stable high concentration products to be manufactured.”
“Other companies have reported using similar sorts of additives in solution formulations but not for processing proteins into dry powders,” Moore told us.
He added the process uses continuous processing, allows drug doses to be altered during clinical development, and the dry powder can be shipped without using cold chain.