On the cover: A formulator at Rentschler Biopharma (WWW.RENTSCHLER-BIOPHARMA.COM)
Quality by design (QbD), risk management, and new technologies are shaping biologics formulation work in the 21st century. We saw much evidence of this at the BioProcess International Conference and Exhibition in Boston last fall, where a wide range of talks filled the Drug Product, Fill–Finish, and Formulations track during the week after Labor Day.
Dingjiang Liu (Regeneron) offered a high-level discussion from the BioPhorum Development Group (BPDG) on “An Intercompany Perspective on Biopharmaceutical Product Robustness Studies.” Such studies ensure that drug products meet quality standards within established ranges. Liu highlighted common themes found throughout the industry, beginning with overall robustness being defined by both formulation and manufacturing processes. Integrating QbD principles, robustness is important to setting critical quality attribute (CQA) control strategies and commercial specifications. Most companies evaluate robustness and apply prior knowledge, risk assessment, and statistics to develop a drug-product design space. Three case studies illustrated study design balancing experimental complexity, statistical power, scientific understanding, and risk.
Arun Jangda (Shire) drilled a bit deeper into the topic with “A Standardized Methodology for Risk-Based Particulate Classification” from the BioPhorum Operation Group’s (BPOG’s) particulate-control workstream. Critical defects are a leading cause of recalls for parenteral drugs, he pointed out. Because regulatory guidances don’t link risk and particulate criticality, the industry is tightening specifications without scientific rationale. “Uncertainty equates to risk of regulatory exposure and challenge,” he said. After the group surveyed 15 leading global biomanufacturers about their practices, it developed a classification tool now available online.
Focus on Drug Products
The trend toward highly concentrated formulations — especially for monoclonal antibodies (MAbs) — isn’t new. But as Avind Srivastava (Avantor) pointed out in “Managing Viscosity for High-Concentration Protein Formulations,” it still comes with challenges. Viscosity is a major concern, and companies like his are developing novel excipients to reduce solution viscosity and help stabilize proteins. (See the “Talking with Thomas Palm” box for more on this topic.)
Other speakers focused on excipients as well. In “Role of Antioxidants in Therapeutic Antibodies: Case Studies, Learnings, and Mitigation Approaches,” Ashaben Patel (Janssen R&D) provided case studies illustrating how oxidation affects biotherapeutic safety and efficacy — and how methionine can protect against it. And in “Potential Impact of Nanoparticulate Impurities from Sugars on Therapeutic Proteins,” Anant Sharma and Nats Rajagopalan (Eli Lilly) showed how those common formulation ingredients can cause protein degradation by reacting with UV light. In Lilly’s work, temperature and agitation appeared to have no effects. But the team is performing additional studies in search of a mechanistic understanding.
The box below features a conversation about excipients at the heart of a recent industry merger.
Keeping Patients in Mind: Highly concentrated formulations present unique questions related to patients’ treatment experience as well — particularly when subcutaneous (SC) injection is the goal. In “Subcutaneous Injection Physiology Research to Improve Biologics Delivery and the Patient Experience,” Michael Harrison (Eli Lilly) showed how the full potential of SC delivery could improve patient care and disease management. But such drugs must be formulated for increased bioavailability as well as safety and efficacy, and they must be delivered with patient tolerability in mind. Harrison emphasized that drug products must “deliver an experience that integrates with patients’ and caregivers’ lives.”
That’s the goal of combination drug–device products, as described by Jeffrey Givand and Steven Persak (Merck Research Labs) in “The Interplay Between User Requirements, Target Product Profile (TPP), and Delivery Device Design Inputs.” Connecting back to higher-level QbD discussions, they showed how a traditional TPP is insufficient to define delivery device requirements when it ignores user capabilities pertaining to the device interface. “Robust collaboration between drug, formulation, and device development teams is critical early (and throughout) product development,” Givand said. Companies need to put the necessary time into innovating or developing required device functionality, especially for highly viscous, large-volume, or lyophilized products.
Focus on Manufacturing Processes
Support technologies are key to the new era in biopharmaceutical manufacturing. In “Advances in Fill–Finish and Drug Product Manufacturing,” Mark Yang (Sanofi) provided an excellent overview of disposables (e.g., vials and fill–finish assemblies), multiformat fillers and isolator technologies, lyophilization with process analytical technology (PAT), drug-product inspections, and modular facilities. And two more speakers highlighted individual process technologies: Frankie Petoskey (Seattle Genetics) with “Impact of Closed-System Transfer Devices (CSTDs) to Drug-Product Quality: The Importance of Comparability Testing,” and Yuh-Fun Maa (Genentech) with “Filling in VaporPhase Hydrogen Peroxide (VPHP) Sanitized Isolators: Uptake and Impact on MAb Drug Product Quality.”
Petoskey’s case study illustrated the need for comparability testing especially when CSTDs are used with potentially hazardous drugs such as antibody–drug conjugates. “CSTD materials of contact are common,” she said. “However, the combination of silicone oil and mechanistic properties of the device can lead to particle generation.”
VPHP increasingly is used for sanitizing fill lines, but companies are realizing that residual presence of the substance could affect product quality. The Genentech group used risk assessment to address it. “Silicone tubing associated with peristaltic pumps is highly permeable to H2O2,” Maa cautioned, “but its uptake behaviors are reversible pending processing conditions and ultimately residual VPHP concentration in the isolator.” Contact time figured heavily into the equation.
Finally, Jia Sun (Genentech) featured a new sample-preparation method with “Progress and Challenges in Automation-Assisted Formulation Development.” The team used an automated liquid handler for design of experiment (DoE) formulation studies. In a case study, they investigated the identities and activities of leachables from containers used in stability studies. “Automation systems bring true benefits to formulation development in both formulation preparation and analytical assays,” Sun said.
Continuing the Discussion
In a sponsored contribution to this special insert on page 10, Rentschler Biopharma reports on its recent market research collaboration with Leukocare that showed the underestimated importance of (but increasing investment in) early stage formulation work, a growing trend toward SC than intravenous (IV) delivery of biopharmaceuticals, and the value of highly concentrated formulations. The authors include a case study featuring a Leukocare formulation platform technology.
At the BPI Conference, Jeremy Duboeuf (Roche) illustrated one trend revealed in those survey results — moving from IV to SC delivery — with his presentation, “Coformulation Development of MAbs and Recombinant Human Hyaluronidase.” Roche added hyaluronidase as a permeation enhancer to assist in SC administration of a highly concentrated MAb formulation, then showed that it did not compromise quality or stability of the robust liquid product that resulted. “Coadministration and coformulations provide patient benefit by reducing treatment time,” said Duboeuf, “and they are less invasive than IV delivery.” His team will be coadministering two different MAb products using the same permeation enhancement technology in future work.
And on page 5, authors from Merck highlight another coformulation project — and the analytical approaches that can assist in development of such products. “Coformulating two or more protein therapeutics into a fixed-dose, single drug product is an emerging strategy for delivering biologics to patients,” they write in their abstract. “Mixing proteins into fixed-dose combinations brings multiple benefits to patients, healthcare providers, and biomanufacturers. Coformulated products do raise additional complexity, however, in terms of formulation and analytical development, product characterization, and immunogenicity assessment. Analytical methods originally developed for individual products need technical advancement for them to adequately evaluate multiple active ingredients in coformulated products. New approaches are required to answer additional questions regarding the mechanisms of degradation, aggregation pathways, and the possible formation of mixed aggregated species in coformulated products. Characterization of fixed-dose combinations of protein therapeutics is a rapidly evolving field that includes defining analytical strategies, developing appropriate analytical assays and tools, and understanding and managing potential product stability risks.”
BPI looks forward to your thoughts and future contributions on these formulation topics and more to keep the discussion going.
Cheryl Scott is cofounder and senior technical editor of BioProcess International, PO Box 70, Dexter, OR 97431; 1-646-957-8879; [email protected].