Essential CMC Elements For A Therapeutic Secretome

By Tyler Menichiello, Chief Editor, Bioprocess Online

I attended Life Sciences Future SW earlier this year, a local industry event put together by the Pittsburgh Life Sciences Alliance (PLSA) and Life Sciences Pennsylvania (LSPA) to unite stakeholders across the region. It was during this event that I first heard about Noveome Biotherapeutics, a Pittsburgh-based biotech company pioneering a first-of-its-kind secretome therapy.

I’d never heard of a secretome therapy before, but I was intrigued by Noveome’s description of its lead product, ST266, as a “cell-free cell therapy” being studied for necrotizing enterocolitis. I became curious about the nature of this product — what exactly is it, and how does it get manufactured? And what does all of that mean from a regulatory and CMC perspective?

Luckily, my friends at PLSA were able to connect me with the company’s chief scientific officer, Larry Brown, Sc.D., who joined me on the “Better Biopharma” podcast to discuss ST266 and the unique CMC considerations around its development and manufacturing.

Below is a video clip from the full podcast episode, which you can find here. Stay tuned for new episodes, released every other Wednesday!

The following transcript has been edited for clarity.

How do you manufacture a therapeutic secretome, and what are the most critical elements of this CMC package given how novel the product is?

Brown: Some of the key challenges are defining the product specifications so that we’re able to make it reproducibly and ensure batch-to-batch comparability. Reproducibility on everything from the contents to the biopotency assays is critical for maintaining product safety and quality.

From a safety standpoint, one of the biggest concerns with most biologics is sterility. Since you cannot terminally sterilize the product, everything has to be done aseptically. We use ultrafiltration to remove any viruses; we screen for a whole array of viruses to make sure they’re not in the final product; and we use commercially available single-use bioreactors.

We’ve had to tweak how we feed the cells and develop a serum-free media. Most people use fetal calf serum to grow cells, which then has to be removed because there’s obviously foreign proteins in there. We made our own proprietary media specifically for these amnion epithelial cells to make them grow over the time period of culturing in the single-use bioreactors.

The secretome is collected continuously during production. At the end, the cells are ultrafiltered out, so we’re left with a solution of growth factors and cytokines.

What’s really interesting is that, if you look at the individual concentrations of any one of these growth factors and cytokines, their individual concentrations are 1 pg/mL or lower. We often get asked, “Which growth factor or cytokine is responsible for the activity that you observe?” It’s not just one. We’ve actually taken recombinant proteins for five or six of them and put them in some of our bioassays, and they don’t work — partially because the concentrations individually are so low, and also because you need more than just those five or six growth factors or cytokines that are implicated in wound healing or anti-inflammatory activities.

We’ve fractionated ST266 by molecular weight to see if there’s any activity associated with one particular fraction. It turned out that certain activities seem to be primarily associated with a certain fraction, while others lack that same bioassay activity, but nothing works as well as the entire secretome.

From a regulatory and CMC point of view, one of our biggest challenges is demonstrating batch-to-batch reproducibility across so many drug components while ensuring that the product can be manufactured consistently. As such, we have a variety of assays. We have one of the most powerful liquid-chromatography-mass spectrometers to characterize the proteome of the product, and a wide array of bioassays that we’re adding to all the time to address the specific activities of the product.

We’ve recently moved into a new facility and built out a cleanroom at the highest standard for biologics production. Ultimately, the biggest challenge I think will be having the FDA come in and inspect us to show that we comply with all regulatory requirements.