Why CGT Manufacturing Still Faces Process Characterization and Scale-Up Challenges, According to MilliporeSigma’s Sebastián Arana

In the second segment of a BioPharm International® interview with Sebastián Arana, global head of Process Solutions, MilliporeSigma, the life science business of Merck KGaA, Darmstadt, Germany, Arana addresses the most pressing manufacturing challenges in the cell and gene therapy (CGT) space as well as key takeaways from the 2026 BIO International Convention (BIO 2026) and the increasing role of collaboration and flexible manufacturing across the biopharma supply chain.

Arana characterizes CGT manufacturing as still in early phases, drawing a comparison to where monoclonal antibody manufacturing stood 25 to 30 years ago. The CGT field continues to rely heavily on manual, customized processes and requires substantial advancement in automation, process optimization, advanced analytics, and real-time monitoring before reproducible, scalable manufacturing becomes standard, he says.

What are the biggest unresolved challenges in CGT manufacturing scale-up?

Arana notes 3 persistent challenges. First, process characterization gaps remain one of the most consistent issues developers navigate. Second, technology transfer has grown increasingly sensitive in biological systems, particularly as therapies manufactured at one site must be reliably transferred to others. Third, analytical readiness consistently lags behind manufacturing scale ambitions, a gap Arana says companies must address proactively as they expand.

"If you cannot manufacture it, produce it, and scale it up at the end, it's just a good idea," he emphasizes.

He also states that post-COVID supply chain lessons have made interdependency and coordination across CGT manufacturing networks even more critical. Speaking on broader BIO 2026 themes, Arana notes confirmation, rather than revelation, that the science is advancing faster than manufacturing infrastructure can absorb. He highlights flexible manufacturing, digital tools, and cross-sector collaboration among large pharma, biotech, suppliers, and contract development and manufacturing organizations as recurring priorities across the conference.

BIO 2026 runs June 22–25 in San Diego.

Watch the first segment of Arana’s interview, and click here for more conference coverage.

About the speaker

Sebastián Arana, Global Head of Process Solutions, MilliporeSigma

At MilliporeSigma, the life science business of Merck KGaA, Darmstadt, Germany, Arana oversees one of the broadest product portfolios in the industry—one that provides a differentiated offering that addresses the full pharmaceutical value chain from upstream to drug product. He has more than 25 years of global experience in marketing, sales, country, and business unit responsibilities, having held executive positions in the United States, Latin America, and Europe. Arana has led teams and managed portfolios across a broad range of industries, including healthcare, consumer, and industrial products.