Hey everyone, it’s Sam from the pilot/clinical manufacturing team here. If you’ve ever worked on clinical trials—whether you’re a researcher, trial site coordinator, or even just someone who’s had a vaccine or medication go through early phases—you know how big a deal quality is. And when I say quality here, I’m not just talking about the drug itself. I’m talking about every tiny step that happens before that drug even gets filled into a vial or a bag, right? Especially when it comes to cleaning and disinfection in clinical manufacturing. Because in clinical manufacturing, you’re not pumping out 100,000 doses a month; you’re making small batches for trials, often with different products, so cross-contamination is a real nightmare. Over the last 7 years, I’ve seen so many teams skip small, practical steps that end up derailing a trial, so I wanted to share what actually works for our pilot/clinical mfg. space, no fancy jargon, just stuff we test every day. Pilot / Clinical Mfg.
First off, let’s get one thing straight: cleaning isn’t the same as disinfection, and in clinical pilot batches, you can’t skip either. A lot of new teams mix these up—they’ll grab a random wipe and call it a day, but that’s how you get leftover protein from a monoclonal antibody batch messing with the next gene therapy trial. Wait, no, let’s make that more relatable. Last year, a small biotech we work with almost lost a Phase 1 trial because they reused a cleaning bucket for two different peptides. The first one’s residual didn’t show up in their swab test until the second batch was halfway done—cost them 2 weeks of delays and $50k in wasted materials. So let’s break down the best practices we live by, starting with the basics: pre-cleaning before disinfection. A lot of people think “if I spray disinfectant, it’ll kill everything,” but no—disinfectants can’t cut through dried-on gunk, right? Like how you can’t sanitize a dirty dish in the sink—you have to scrub the food off first. For our lines, pre-cleaning means immediate “wipe down as you go” for small equipment (like beakers, stir plates, vial filling nozzles) between runs, and a bulk pre-rinse with room temp water first, then a warm detergent rinse. Not hot water—hot water can set protein residues, that’s a trick we learned the hard way when we burned a batch of insulin precursors in 2020. We use a pH-neutral detergent, not industrial-strength, because industrial ones leave residue too, and for clinical stuff, you don’t want that. Once that pre-cleaning is done, you let the surfaces dry completely before disinfecting. Damp surfaces dilute disinfectant, so that’s another mistake I see all the time.
Next up: picking the right disinfectant, and not just grabbing whatever’s cheap. In pilot manufacturing, the equipment changes a lot—one day it’s a viral vector line, the next it’s a small-molecule batch, and sometimes you have a mix. So we rotate between two disinfectants, not mix them (super important—mixing bleach and alcohol, for example, makes toxic gas). We use 70% isopropyl alcohol for hard, non-porous surfaces like stainless steel tables and filling nozzles, and accelerated hydrogen peroxide (AHP) for softer stuff like plastic tubing that touches the product. Why 70% alcohol, not 90%? 90% evaporates too fast, it doesn’t actually kill germs inside the cell walls, right? We tested that once—swabs after 90% alcohol still had bacterial spores, but 70% did the trick. And AHP is good because it breaks down into water and oxygen, no residual weirdness, which is key for clinical batches where you don’t want leftover chemicals interacting with the trial drug. Also, we never use quaternary ammonium compounds (quats) as the main disinfectant here—they leave a film, and some microbes are resistant to them now, which is a problem when you’re dealing with sensitive clinical materials.
Then there’s the SOP (standard operating procedure) thing, but let’s make it real—SOPs don’t work if no one follows them, because it’s pilot manufacturing, teams are juggling 10 things at once. We have what we call “quick check” lists that are taped next to every work station, not a 20-page binder no one reads. Like, for a vial filling run, the quick check has 5 bullet points: 1) Swab 3 spots on nozzle post-clean, 2) Wipe table with AHP, 3) Change gloves before handling new batch components, 4) Log disinfectant expiration date (we throw away any opened disinfectant after 7 days, even if the bottle says it lasts 30—opened bottles get contaminated fast), 5) Dry all surfaces for 10 mins before starting. That’s it, no fluff. We also do random third-party swab tests, not just the required ones—like, last month, we had a new temp worker skip the 10-minute dry time, and our random swab after that showed a tiny bit of residual disinfectant on the nozzle. We pulled that batch, no questions, because even a tiny amount could mess with the trial results.
Wait, and what about personnel? That’s a huge part of cleaning and disinfection that a lot of teams overlook. It’s not just the surfaces—your hands, your coats, your gloves. We have a “glove change every batch rule,” and not just when they get torn. If you switch from working on a cell therapy line to a small molecule line, you change gloves and do a quick hand wash with antibacterial soap (but not too strong, because we don’t want to mess with the microbiology of the clean room). We also have weekly deep cleans for all the HVAC filters in our pilot suites—you might not think that’s part of cleaning and disinfection, but if your air is blowing contaminated particles around, all the surface wipes in the world won’t help. Last winter, we had a filter that wasn’t changed, and we found mold spores in one of our clean rooms—we had to shut down that line for 3 days, which delayed a Phase 1 trial by a week. So HVAC maintenance isn’t a “big plant thing,” it’s a pilot mfg. thing too.
Another big one: documentation, but again, make it simple. We use a Google Sheet (shocker, I know) that each worker logs their cleaning steps into—batch number, time cleaned, disinfectant used, swab results. No more paper logs that get lost or messy. If an auditor comes in, we can pull that sheet in 2 seconds. And if something goes wrong—like a swab test comes back positive—we flag it immediately, not hide it. A few years ago, we had a swab that had residual from a previous batch, and because we logged it, we traced it back to a worker who reused a cleaning wipe instead of grabbing a new one. We fixed that, trained the team, and didn’t have a problem since. Hiding mistakes in clinical mfg. is the worst—you could get a whole trial stopped, and that’s not fair to the patients who are volunteering to test new drugs.
Wait, let’s talk about common mistakes specific to pilot/clinical mfg., not commercial. Commercial mfg. runs the same batch every week, so they have set processes, but pilot is all about change—one week you’re making 50 doses of a new antibody, the next week you’re doing stability testing on an old drug. So cross-contamination risk is way higher here. That’s why we do a “line clearance” between every batch, even if the next product is the same. Line clearance means swabbing not just the equipment, but the floor around the line, the control panel, even the door handle to the clean room. We had a client a while back who skipped line clearance because they said the next batch was the same small molecule, and their swab test still had residual from the previous run. They had to toss all 50 doses, which cost them over $100k, and the trial was delayed. So line clearance non-negotiable, no exceptions.
Also, for the small stuff—like tools. We have a bin for cleaning tools (brushes, tweezers, nozzles) that only gets used for that purpose. We don’t take a brush from the lab’s general supply to scrub a line, because that brush might have been used for something else. After each use, those tools get soaked in detergent, then disinfected with alcohol, then air-dried. We check them weekly for any cracks or scratches, because scratches hold residues and microbes that you can’t clean out. That’s another thing I learned—if a stir plate has a tiny scratch on the metal, you have to replace it, not just keep using it. Scratches are like hiding spots for gunk.
What about clean room attire? A lot of pilot teams skip the full bunny suit (the hood, face mask, gloves, boot covers) for small runs, but that’s a mistake. Even if you’re only in the clean room for an hour, your hair has oils, your hands have bacteria, that can get on the equipment. We require full PPE for all clinical mfg. runs, even the 50-dose ones. Last year, we had a worker wear a ball cap instead of a hood, and a strand of hair fell into the vial filling line. We caught it before filling, but if we hadn’t, that would have been a huge issue. So PPE isn’t just a rule—it’s part of cleaning and disinfection for personnel.
Let’s talk about testing, not just swabs. We do weekly microbial monitoring of all our clean rooms—air samples, surface samples, even water samples for the equipment that uses water (like for mixing batches). We use culture plates that sit in the clean room for 24 hours, then count the colonies. If we get more than 1 colony, we investigate. That’s different from the line swabs, which are for residue testing. Residue testing is for the specific product from the previous batch, and microbial testing is for general germs. Both are needed, and you can’t skip either.
Wait, and when a batch is done, what’s the post-run clean? For pilot runs, we used to leave equipment until the next day, but now we do a post-run clean right after the last dose is made, even if it’s 10 PM. Because if you leave the dried-on residue overnight, it’s way harder to get off. We had a batch where we left a beaker with peptide residue over the weekend, and when we tried to clean it on Monday, we had to use a stronger detergent that left a smell, which meant we had to replace the beaker. So post-run clean immediately—no waiting.
Now, let’s get to what doesn’t work, because I don’t want you wasting time. First, don’t mix disinfectants—bleach and alcohol make chloramine gas, which is toxic, and you can get sick. We had a temp worker do that once, and he had to leave the clean room for an hour, delayed a batch, and that’s not worth it. Second, don’t use generic household disinfectants. They might kill germs, but they leave residue that interacts with clinical drugs—we tested a generic bathroom wipe once, and it left a chemical that made an antibody batch lose 15% of its activity. Bad news. Third, don’t skip dry time. I can’t stress that enough—disinfectant needs contact time, which usually means letting it sit for 1-2 minutes, then drying. If you wipe it off right away, it didn’t do anything. We’ve seen that happen too many times.
And finally, what’s our takeaway as a pilot/clinical mfg. supplier? It’s not about following a 100-page FDA guide to the letter (though we do follow FDA guidelines, obviously)—it’s about practical, consistent steps that fit the small-batch, fast-paced nature of clinical trials. The best practices here are the ones that don’t add 2 hours to your workday, but still prevent delays, wasted materials, and most importantly, protect the trial patients and the integrity of the drug.
If you’re a biotech team, a trial sponsor, or a research lab that needs help with cleaning and disinfection for your pilot clinical manufacturing runs, we’re here to work with you—we don’t do one-size-fits-all, we adjust our processes to fit your specific product, timeline, and needs. No fancy sales pitch, just real experience, like the kind I shared here. Reach out to our team to chat about how we can make your clinical mfg. cleaning and disinfection process smooth and reliable.
Production TFF System References:
- FDA. (2022). Guidance for Industry: Sterile Drug Products Produced by Aseptic Processing — Current Good Manufacturing Practice. U.S. Food and Drug Administration.
- ISPE. (2021). Good Practice Guide: Cleaning Validation in Pharmaceutical Manufacturing. International Society for Pharmaceutical Engineering.
- CDC. (2020). Guidelines for Disinfection and Sterilization in Healthcare Facilities (2008), Updated for Pharmaceutical Manufacturing Settings. Centers for Disease Control and Prevention.
- PDA. (2019). Technical Report No. 49: Disinfection in Pharmaceutical and Biopharmaceutical Manufacturing. Parenteral Drug Association.
Hangzhou Guidling Technology Co., Ltd.
Address: No.795, 18th Street, Qiantang New District, Hangzhou City, Zhejiang Province, China
E-mail: export1@guidling.net
WebSite: https://www.guidlingfiltration.com/
