Clarity in every step of science.
Your lab, amplified by experts in viral clearance and viral safety. Science that earns confidence. Partnership that earns trust.
Depth where the risk is highest
Viral clearance and custom cell culture each account for roughly half of what we do. Every study is scoped to the question your program needs answered, and to the questions a reviewer is likely to raise next.
Viral clearance studies
Study design comes before the risk sets the timeline.
We characterize and validate viral clearance across your purification steps, scoped to the guidance your submission will be reviewed against — with scale-down models that hold up to scrutiny.
- Spiking studies
- Process step evaluation
- ICH Q5A framework
- Scale-down models
- Solid & tissue matrices
- GLP study design
Custom cell culture
An equal half of the practice.
Frederick opened as a cell-culture laboratory in 1991 and never stopped being one. Research cell bank generation, recombinant line generation, expansion, characterization, and cryopreservation in a continuously monitored facility.
- Research cell banking
- Conditioned medium production
- Cell line expansion
Virus Production & Viral Safety Testing
Find the risk while there's still time to act on it.
Adventitious agent detection, cell bank characterization, and biosafety testing surface contamination and identity risk early, before it reaches your program's critical path.
- Adventitious agents
- Cell bank testing
- Mycoplasma & sterility
Potency assays & custom bioassays
Assays scoped to the decision the data has to support.
Potency testing for plasma-derived products against recognized reference standards, plus custom bioassay development and matrix assessment before testing begins.
- IGIV potency testing
- Measles & polio
- Diphtheria toxin
- Matrix & interference assessment
Where the methods come from
Cytaclar is a new name on laboratories that have been doing this work since 1991. The name changed in 2026. The people, the sites, and the science did not.
Why the work started
In the 1980s, a series of contamination events involving blood-derived products and HIV made one question urgent: can you prove a product is safe before it reaches a patient?
In 1987, Professor Florian “Nardi” Horaud (1925–2000) founded the Texcell laboratory inside the Institut Pasteur in Paris to answer it. Horaud advised the World Health Organization and represented the European position at the International Conference on Harmonisation. The team assembled there ran some of the earliest viral validation studies, using HIV-1 strains characterised at the Institut Pasteur.
That is where these methods come from — first in Europe, then the United States and Asia.
Origins at the Institut Pasteur
The organization traces back to a viral safety service laboratory founded at the Institut Pasteur in Paris.
Frederick, Maryland, founded as Cell Trends, Inc.
A custom cell-culture laboratory opens in Maryland. Custom cell culture has been a core service continuously since.
Viral testing and viral clearance added
The Frederick site extends from cell culture into viral safety testing and spiking studies for biologics sponsors.
Joins an international biosafety group
Frederick is acquired by Texcell Group and becomes its North American laboratory.
Asia office established
Japan office established
China office established
Capacity quadrupled; Shanghai opens
A new viral clearance facility with eight dedicated client suites opens in Frederick. In the same year the Shanghai laboratory begins operating.
Dual-virus multi-spike method published
The multi-spike approach developed at Frederick is published in Biotechnology and Bioengineering.
Cytaclar
The Frederick and Shanghai laboratories operate under a single new brand. Same teams, same studies, same contacts.
Multiple viruses, one load, unchanged quantitation.
The objection to multi-spike clearance has always been interference: if two viruses share a test material, can you still trust each titer? We tested it directly. Using virus-specific indicator cell lines and TCID50 endpoints, multi-spike results tracked their mono-spike controls to within one log10 across three test materials in triplicate, on every pair evaluated.
It pays off most where test material is scarce, AAV programs in particular, and where chromatography run count drives cost. We offer dual- and triple-spike options; inquire for more details.
Horne HB, Lindsey TB, Wolfe LS, Chumbris S, Dickson M, Iheanacho A. Application of a dual virus spike approach to accelerate early-stage viral clearance studies. Biotechnology and Bioengineering. DOI 10.1002/bit.70085. Supports ICH Q5A(R2) and is complementary to ICH Q14.
Viral clearance on materials that never see a column
Clearance methodology assumes a liquid process stream. Solid and tissue-derived starting materials break that assumption, and the study has to be built differently from the ground up.
A solid cannot be spiked like a load
The limiting factor is recovery, not reduction.
In a liquid process you spike the load, run the step, and titrate the pool. A solid starting material offers none of those handles. Virus has to be applied so that distribution across the material is controlled and reproducible, then recovered from the matrix before it can be quantified at all. In practice the recovery you can demonstrate, rather than the performance of the processing step, is what sets the ceiling on the log reduction you can defensibly claim.
Studies are executed at our Frederick laboratory under the same GLP quality system as our liquid-stream clearance work, and scoped to the clearance claims your submission has to support. We support solid and tissue-derived matrices including bovine and porcine tissue, hide and dermal material, bone, tendon, collagen, gelatin, and pericardium.
- Controlled spike application and distribution
- Extraction and recovery from the matrix
- Cytotoxicity and interference in extracts
How much of the process you run is up to you
You supply the reagents, columns, and filters needed to reproduce your steps at scale-down. We handle the rest.
You run your process, in our laboratory
Your team executes the scaled-down process on site. We perform virus spiking, provide the virus panel, and perform the titrations.
We run it alongside you
Our staff assist your team in executing the scaled-down process at our laboratory.
Tech transfer, and we execute
The scaled-down process is transferred to us and our personnel execute the entire study. No travel, no bench time from your team.
Not sure the process is ready for a definitive study? Start with a for-information-only (FIO) study. Non-GLP, fast, and priced to be affordable before the process is locked, it tells you what log reduction a step can actually achieve, and leaves time to optimize if the answer is not what your regulatory package assumed.
The standard every study runs under
We operate to the FDA Good Laboratory Practice regulations, 21 CFR Part 58. GLP is an enforceable set of requirements covering who is accountable, what gets recorded, and whether a reviewer can reconstruct the study from the data.
One accountable Study Director
Part 58 assigns overall responsibility for a study to a single named Study Director. That person is on your protocol, answers your questions directly, and signs the final report.
Independent quality assurance
A quality assurance unit separate from the people running the study inspects critical phases, holds the records, and issues the statement that accompanies the final report.
Protocol first, deviations on the record
The protocol is approved before work begins. Amendments and deviations are documented as they happen and reported in the study record.
Raw data that rebuilds the study
Records are contemporaneous, attributable, and retained in a controlled archive, so the reported result can be traced back to the observation it came from.
Our data integrity commitment. The data you receive is the data we generated, reported as observed and traceable through the study record. You get a complete and current picture of your process, with the evidence behind it, in time to act on what it tells you.
For-information-only studies are non-GLP by design and are labeled as such in every deliverable, so the regulatory status of every dataset is clear from the moment you receive it.
What sponsors rely on us for
Deep expertise in the areas where accuracy matters most, and the scientific judgment to know what your program needs.
Regulatory-ready science
Study design, documentation, and rationale built to be reviewed. Evidence that holds up under scrutiny.
Specialized biosafety expertise
Viral clearance, custom cell culture, viral safety, and bioassays are the center of our practice.
Direct scientific access
You reach the scientist working on your program, with practical planning and early escalation the moment complexity appears.
Explore both locations
Hover a marker to see how each location fits your program. On touch devices, tap a marker.
Cytaclar Frederick
Our GLP laboratory, operating to 21 CFR Part 58, built for FDA, EMA, and ICH review. Formerly Texcell North America.
Cytaclar Shanghai
Viral clearance and viral safety testing for sponsors across Asia, with same-time-zone support and documentation prepared for global submissions such as NMPA, USFDA, EMA and PMDA.
Have a study to design, or a result you can't yet explain?
Tell us what your program needs to prove and where it's under pressure. A senior scientist will respond directly.