Describe your process. Studio builds the model.
Tell Studio whether you run a batch, fed-batch or continuous process, describe it in silico and bring your data. Studio searches the model settings, ranks the candidate models on your runs and keeps the best, so you get a model that predicts process performance and product quality without building it by hand.
A process model without the modelling work
You bring the campaign data you already have and describe your upstream process in the terms you already use. The reactor model workflow in Novasign Studio turns that description into a process model, so your time goes into the process rather than into the model.
With the model trained, you can try conditions that have never been run in a lab and see how the process would have behaved. The model suggests which conditions are worth testing next and which setpoints move you towards your objective, and you decide which of them are worth a vessel.
You define the model once and retrain it on every new experiment, from early development across scale-up to manufacturing.
Your host, your product, one workflow
The workflow models any host and any product class. A CHO fed-batch, a viral vector production run and a Komagataella phaffii fermentation are described with the same workflow, and what changes is which performance metrics and quality attributes you are interested in. The way you describe the reactor stays the same.
Modalities also differ in how a run is staged. An induction, a carbon switch, a temperature shift or a transfection each opens a new phase in the bioprocess, and every one of them can be defined in the model. These are examples of what is supported.
| Performance metrics | Quality attributes | Process events | |
|---|---|---|---|
| Mammalian cell culture | Viable cell density, product titer | Charge variants, glycoforms, aggregation | Temperature shift, feed start |
| Cell and gene therapy | Viable cell density, viral titer | Full-to-empty ratio, dsDNA, host-cell protein | Transfection, infection at a chosen multiplicity |
| mRNA | RNA yield | Integrity, capping efficiency, poly(A) tail length, dsRNA | Template addition |
| Microbial fermentation | Biomass, product titer | Aggregation, host-cell protein | Feed start, induction |
| Precision fermentation | Biomass, product titer | Aggregation, host-cell protein, glycosylation in yeast hosts | Induction, carbon switch |
| Microalgae and cyanobacteria | Biomass, chlorophyll a, polysaccharide titer | Released share of total carbohydrate | Light intensity changes |
Mammalian cell culture
- Performance metrics
- Viable cell density, product titer
- Quality attributes
- Charge variants, glycoforms, aggregation
- Process events
- Temperature shift, feed start
Cell and gene therapy
- Performance metrics
- Viable cell density, viral titer
- Quality attributes
- Full-to-empty ratio, dsDNA, host-cell protein
- Process events
- Transfection, infection at a chosen multiplicity
mRNA
- Performance metrics
- RNA yield
- Quality attributes
- Integrity, capping efficiency, poly(A) tail length, dsRNA
- Process events
- Template addition
Microbial fermentation
- Performance metrics
- Biomass, product titer
- Quality attributes
- Aggregation, host-cell protein
- Process events
- Feed start, induction
Precision fermentation
- Performance metrics
- Biomass, product titer
- Quality attributes
- Aggregation, host-cell protein, glycosylation in yeast hosts
- Process events
- Induction, carbon switch
Microalgae and cyanobacteria
- Performance metrics
- Biomass, chlorophyll a, polysaccharide titer
- Quality attributes
- Released share of total carbohydrate
- Process events
- Light intensity changes
Any attribute you measure can be used as a quality attribute. Contact Novasign if your modality is not mentioned.
You describe the process. Studio sets up the model.
Setup has two halves, your upstream process and the machine learning.
In the words you already use
Each half keeps its own vocabulary: process parameters and quality attributes for your process, loss functions and checkpoints for the machine learning.
The bioprocess side: parameters, components and feeds
Whichever controller software your runs were recorded with, the data can come in. Exports from Sartorius Ambr, Eppendorf DASGIP or Thermo Fisher systems come in as CSV or Parquet files, a Qubicon system connects directly, and custom-built infrastructure connects through the custom-code node. Historian exports come in as CSV or Parquet files.
Raw process data rarely arrives ready to model, which is why data processing is part of Novasign Studio in its own right: the dataframe nodes that clean and align a campaign run in the same workflow. What matters for the user is that the processing is reusable. You set it up once and it runs again on the next campaign, the same way the reactor model does.
The setup then walks you through your process.
- 1Initial
- 2Process Parameters
- 3Components
- 4Feeds
- 5Trainer
- 6Tuner
- 7Training Preview
| Name | Unit |
|---|---|
| pH | dimensionless |
| Temperature | °C |
| Multiplicity of infection | dimensionless |
Initial configuration
Working volume, the time base, and the run IDs that separate one run from the next, so a whole campaign arrives as one table.
Process parameters
The parameters that are recorded and actively set during the run, and that the model should account for: temperature, pH, dissolved oxygen and stirrer speed, among others.
Components
Everything that is in the reactor or can enter it, whether present at the start, added or removed throughout the process or produced over time. Set cells, substrates, products and define material attributes, performance metrics and quality attributes.
Feeds
Every addition that was recorded, from a substrate feed or base to a one-off event like an induction or a transfection. A feed that differed between runs is a column rather than a number.
Every column is defined with its unit, °C, % or g/L, so the mass balances stay dimensionally consistent and nobody has to rescale a column by hand to make them add up.
The machine learning side: model training, tuning and selection
Trials save checkpoints as they train, and the model you carry forward is selected from them, as for every Studio model.
- 1
Train
Training fits the model to your data, with defaults chosen for reactor processes rather than for machine learning in general.
- 2
Tune
Tick tunable next to a setting and the tuner sweeps it in one pass instead of one candidate at a time.
- 3
Select
The selector chooses between the candidates, automatically in most cases or against criteria of your own.
| Epoch | Checkpoint | Validation RMSE | Flags |
|---|---|---|---|
| 0 | epoch_00 | First | |
| 4 | epoch_04 | ||
| 8 | epoch_08 | ||
| 12 | epoch_12 | ||
| 16 | epoch_16 | ||
| 20 | epoch_20 | ||
| 21 | epoch_21 | Top | |
| 24 | epoch_24 | Final |
Try the runs you have not done
With a trained model you can simulate runs that were not performed. The digital twin takes the trained reactor model, adds a simulation configuration, and returns trajectories for everything the model was trained on: cells, substrates, product, and the quality attributes you measured, whether that is the glycoform of a monoclonal antibody or the viral titer of a viral vector process.
The decisions the digital twin helps you make
Which decision you face depends on the phase of the lifecycle the process is in.
- Screening
Do these process parameters influence the process at all?
Vary them across the space and watch what the performance metrics and the critical quality attributes do. A parameter that moves nothing is one fewer to characterize.
- Optimization
Which conditions give the best performance at acceptable quality?
State the objective and the ranges to optimize within, and run the simulations inside that space. Every in-silico run can be read in a table or a chart. The visualizations and statistics show you which experiments are worth performing. Once the model has earned your trust, the workflow proposes the next set of experiments for you.
- Characterization
How robust is the process inside its design space?
Restrict the acceptable ranges of your critical quality attributes and what remains is a design space. Vary the process inputs inside it, and how much the outputs move is your answer on robustness.
- Scale-up
Which conditions are suitable for the move to a larger vessel?
Of the conditions that give acceptable results at lab scale, which ones are physically and biologically possible at scale? The hybrid model answers for the culture, and the CFD model of the target vessel answers for the vessel.
Configuring a simulation
A simulation adds the initial state of the reactor and the phases of the process to what the trained model already knows. Letting the configured phases drive the prediction is in development.
The initial state is the filling level and the media the reactor starts with. Changing it is how you simulate a different scale or a different media composition.
Your vessel enters the model through computational fluid dynamics (CFD). CFD models of your vessels, from Novasign’s technology partner SimVantage, give the kLa, shear and mixing of every run, and the Reactor feeds them into the hybrid model. The hybrid model learns what the culture does, and the CFD describes what the vessel does to it. See how Arkeon scaled up from 2 L to 150 L.
A phase is a section of the upstream process, and which ones you have depends on the modality: pre- and post-transfection in gene therapy, pre- and post-temperature-shift in cell culture, batch, growth and production in a microbial fermentation. Each phase is defined by three things.
Process parameters
Every phase has its own set of setpoints.
Feeds and outflows
Feeding strategies cover continuous feeds from constant through exponential, spiked feeds, and feeds that react to the current process state. Outflows are defined the same way, whether continuous like a perfusion culture or one-off like periodic sampling.
Stop criterion
A time, a volume, or a concentration target. The first to fire ends the phase and starts the next.
- 1Process Parameters
- 2Components
- 3Feeds
- 4Initial Conditions
- 5Phases
- 6Sweep Space
- 7Simulation Preview
- 1Batch phase
- 2Growth phase
- 3Production phaseProcess parameterspHdimensionlesstunabletunableTemperature27°CtunabletunableFeedInflow strategyExponential feedSpecific growth rate0.151/hStop criterionStop time80htunabletunable
Generating the in-silico runs
The digital twin lets you run the process in silico for a new set of inputs.
The example below is a simulation built on data from a viral vector process in which pH, temperature and multiplicity of infection were investigated systematically. Move the sliders and the twin simulates cells, product and the impurities, dsDNA and host-cell protein, for each condition.
Simulation inputs
pH 7.2; Temperature (°C) 33 °C; Multiplicity of infection 0.003; Cells on micro-carrier highest predicted 1.12 ×10⁶ cells/mL at 80 h; Virus titer highest predicted 6.923 log₁₀ TCID50/mL at 160 h
Highest predicted value
Cells on micro-carrier
1.12 ×10⁶ cells/mL
highest predicted · at 80 h
Virus titer
6.923 log₁₀ TCID50/mL
highest predicted · at 160 h
The data comes from a collaboration with Bespark*bio: Bespark*bio performed the experiments and Novasign created the model.
In collaboration with Repligen, the digital twin was used to predict the glycoform and glycation of a biosimilar when temperature and target glucose concentration change. The twin shows which conditions yield the required ranges of the critical quality attributes, and that defines the design space for the process while optimizing for product titer.
Quality criteria
Highest predicted value
Predicted IgG titer
1.63 g/L
highest predicted titer inside the current windows
| Predicted titer and the current windows | Predicted IgG titer 1.08–1.63 g/L; Highest predicted value 1.63 g/L |
|---|
Start with one process question. See what your data can do.
Bring one process and the campaign data you already have. We work with you on a scoped proof of concept, so what comes out is a model of your process rather than a demonstration on somebody else’s. Not a standard unit? Scientific modelling models it with you.
From the reactor
Online sensors, soft sensing and what they make possible in the vessel.
BioprocessNov 16, 2021Advanced online sensors for monitoring and modeling of HEK 293 gene therapy processes
Emerging manufacturing technologies to treat diseases derived from monogenic disorders are of high importance for upcoming gene therapy approaches and by 2019, almost 150 unique clinical trials were reported. For such an in vitro and in vivo gene delivery, recombinant adeno-associated viruses…
BiotechnologyHybrid ModelingOct 15, 2020Novasign Soft Sensing Technology at Siemens’ LivingLab
Innovative tools to monitor important upstream bioprocess variables in real-time, such as biomass, are of high interest for manufacturers. Typically, to get these values, a sample must be drawn, processed, and analyzed. These steps lead to an inevitable time delay, which makes this desired…
Dec 23, 2021Reduced experimental burden in CHO process development across scale: hybrid modeling and iDoE
Process development in a QbD approach is accompanied by high experimental effort due to a design of experiments (DoE) approach at different scales, consuming large quantities of raw materials and time. For upstream process development of mammalian cell culture, this procedure is highly exhausting…