From Lab to Scale: The David Friedberg Checklist for Biomanufacturing Readiness
A practical David Friedberg-style checklist to prove biomanufacturing readiness—from fermentation and DSP to COGS, PAT, and financing. Get scale-up right.
David Friedberg often gets asked a simple but brutal question in biomanufacturing: when is a process really ready to scale.
I hear this question every week from founders and operators who feel stuck between exciting lab data and the harsh reality of pilot runs, capital budgets, and COGS.
In this guide, I lay out a practical, no-nonsense readiness checklist inspired by the way David Friedberg talks about biomanufacturing economics and scale-up discipline.
You’ll learn how to stress-test your fermentation, process development, downstream, cost model, and go-to-market plan before you burn cash on steel and capacity.
I share hard-won lessons, simple tests, and patterns that separate winners from costly science projects.
From Lab to Scale: The David Friedberg Checklist for Biomanufacturing Readiness
1) What Is the David Friedberg Biomanufacturing Readiness Checklist
I think of the David Friedberg checklist as a tough-love filter for any biomanufacturing program claiming it’s ready to scale.
It forces clarity on five questions.
Do you have product/market clarity. What exactly are you selling, to whom, at what spec, and how will they validate it.
Do you have a repeatable bioprocess. Can you hit the same results three runs in a row on a relevant scale-down model.
Do you have a credible COGS and capacity model. Can you produce at a margin that supports a business, not a paper.
Do you have a de-risked scale-up path. Are kLa, OTR, P/V, mixing time, and heat removal accounted for with scale-appropriate correlations.
Do you have a financing and partner plan. Can you fund the path and secure the right CDMO or facility without losing time or control.
If you can’t answer yes to all five, you’re not ready yet.
That’s not a critique.
That’s the checklist doing its job.
2) Why Lab-to-Pilot Readiness Matters More Than Your Best Flask Result
I’ve watched beautiful bench data die at 300 liters because of one missing link: a validated scale-down model that mimics large-scale hydrodynamics.
At bench scale, oxygen transfer is easy, heat removal is trivial, and mixing is instant.
At pilot scale, oxygen transfer becomes the taxman, heat removal fights you in exothermic runs, and antifoam wrecks downstream yield.
Here’s my short rule.
Flask wins don’t pay rent. Reactor wins do.
Biology that only works gentle is biology that won’t ship.
Three-good-runs in a scale-down model beat one miracle titer every time.
If you’re serious about scale, make your bugs and your DSP earn it in a realistic, mean-spirited model of your future plant.
3) Define the Product and Spec Before You Touch a Reactor
The fastest way to waste a year is to scale a process before you lock the product spec and the customer validation path.
I always ask founders to write a one-pager that answers five things.
Use case. What job does this molecule, organism, or material do.
Must-have specs. Purity, potency, activity, particle size, moisture, endotoxin, residual solvents, or any industry-specific metric.
Acceptance test. How will your customer test and approve a lot.
Packaging and shelf-life. What format goes to the customer and how long is it stable.
Regulatory classification. Food, feed, cosmetic, industrial, or pharma-grade, with the matching documentation burden.
When you lock this, your process development gets laser focused and your COGS model turns from fiction into a plan.
4) Strain and Construct Readiness: Stability Beats Hero Titers
I’ve seen founders chase a headline titer and then watch the strain drift during a 14-day run.
That’s not readiness.
Here’s what I look for before scale-up.
Genetic stability under stress. Run serial subcultures and long batch times with selective pressure off and on.
Clear copy number and expression control. Avoid designs that depend on perfect induction timing to work.
Process-tolerant strains. Strains that tolerate shear, antifoam, pH swings, and nutrient limitations will save you time later.
Freedom to Operate. Do an honest IP scan and lock your FTO early or risk rework.
Stability and robustness beat a fragile race car strain every day at production scale.
5) Fermentation TRY Targets: Define the Line in the Sand
Every bioprocess lives and dies on TRY: titer, rate, and yield.
I ask teams to set a simple target table that ties TRY to COGS and price.
Titer. How many grams per liter do you need to hit your cost model.
Rate. Volumetric productivity drives tank turns, revenue per reactor, and capacity planning.
Yield. Substrate-to-product yield determines raw material cost and waste.
Make three boxes.
Green. On-model and fundable.
Yellow. Viable but margin-sensitive.
Red. Uninvestable without a price or spec change.
Then run your experiments and report against those boxes like a business, not a paper.
6) Scale-Down Models and Scale-Up Criteria: kLa, OTR, P/V, and Mixing Time
Scaling is not a vibe.
It’s math plus scar tissue.
Pick your scale-up criteria and stick to them.
kLa. If oxygen is limiting, match volumetric oxygen transfer coefficients across scales.
OTR with safety margin. Calculate OTR needs at peak respiration and leave headroom.
P/V. Power per volume is a workhorse surrogate for mixing and shear.
Tip speed and mixing time. Don’t scale shear-sensitive cultures on P/V alone.
Heat removal. Model duty and check jacket/coil capacity at the pilot and production scale.
Build a scale-down reactor that mirrors your target plant geometry, baffles, impellers, and spargers.
Run it like the plant will run.
That means real gas flows, antifoam strategy, and CIP/SIP cycles that your biology has to survive.
7) Downstream Processing: Lock the Big Decisions Early
Downstream destroys margins quietly if you ignore it.
Pick a primary recovery and purification strategy that respects physics and scale.
Cellular vs secreted. Intracellular products drive lysis and solids handling costs, while secreted products shift burden to filtration and concentration.
Capture step. Affinity is great for purity, bad for resin cost at scale unless you recycle aggressively.
Solvent and antifoam management. Anything you add upstream shows up downstream as cost and risk.
Crystallization or formulation. If the market accepts a technical-grade or formulated product, lock that decision early to shrink polishing costs.
Run mass balances and yield ladders for each DSP concept and choose the simplest path that meets spec.
8) Quality by Design and DOE: Map Your CPPs and CQAs
If you can’t state your Critical Quality Attributes (CQAs) and the Critical Process Parameters (CPPs) that control them, you’re not ready.
I use a simple QbD flow.
Define CQAs. The quality outcomes the customer cares about.
Hypothesize CPPs. Variables like pH, feed rate, temperature, induction timing, and harvest time.
Screen with DOE. Use fractional factorials or response surface designs to map sensitivity quickly.
Set proven acceptable ranges. Lock them in your batch records and train the team.
QbD is not paperwork.
It’s the operating system for reproducibility.
9) PAT and Data Backbone: Measure What Matters in Real Time
Real processes watch themselves.
If you only see what happened after the batch is over, you learn slowly and lose money.
I advise teams to implement lightweight PAT and a data backbone early.
I’ve made most of these mistakes and watched others make the rest.
Mistake. Letting research-grade variability into production-line experiments. Fix. Define release criteria for every input, even at bench scale.
Mistake. Ignoring cleaning and turnaround times in capacity models. Fix. Model CIP/SIP cycles and downtime honestly.
Mistake. Over-relying on affinity capture. Fix. Explore precipitation, ion exchange, or crystallization if the market tolerates technical grade.
Mistake. Shipping beta samples that don’t match future spec. Fix. Only send production-representative material or label it explicitly as exploratory.
Mistake. Underestimating analytics burden. Fix. Staff QC early and automate where possible.
Generative AI Assist for Readiness
I use AI as a force multiplier, not a replacement for domain expertise.
Protocol normalization. Standardize SOPs and highlight step conflicts.
COGS scenario sweeps. Rapid what-ifs with parameter sweeps tied to TRY and yield ladders.
Deviations triage. Summarize batch records and suggest likely root causes tiered by impact.
Vendor intelligence. Draft supplier comparison matrices to review with humans.
AI helps you move faster if you feed it clean data and keep a human in the loop for plant realities.
The Biomanufacturing Readiness Score: A Simple Self-Test
Score yourself from 0 to 2 on each line and add them up.
Product spec locked and validated.
Upstream reproducible at scale-down.
Downstream yield ladder locked.
Defined scale-up criteria.
PAT and historian in place.
COGS model with three scenarios.
Supply chain dual-sourced.
Regulatory path aligned.
EHS cleared.
Capital covers next two gates.
18–20 is investable now.
12–17 is close with targeted fixes.
Below 12 means pause, focus, and rebuild the plan.
FAQs
What is biomanufacturing readiness.
It’s the point where your process is reproducible, your cost model works, and your customers can accept your product.
Why is David Friedberg associated with this topic.
He consistently highlights the economics and discipline required to make biomanufacturing commercially viable, which inspired this practical checklist.
What TRY targets do I need before pilot.
Set TRY tied to COGS and price, then run three consecutive green runs in a scale-down model to validate readiness.
How do I choose scale-up criteria.
Match constraints to biology and equipment, usually kLa or OTR for oxygen demand, plus P/V, mixing time, and heat removal capacity.
When should I lock downstream steps.
As soon as you define the product spec and run a yield ladder that meets cost and quality in three independent runs.
Do I need GMP to start.
Not unless your market requires it. Choose the regulatory path early and align your documentation to that path.
What’s a reasonable pilot success metric.
Reproducible batches that match scale-down profiles, on-spec output, and learning that de-risks production scale economics.
How do I build a credible COGS model.
Use three tabs for COGS, capacity, and CAPEX, with base, upside, and downside scenarios tied to measured TRY and yields.
When should I engage a CDMO.
After you can document your process narrative, CPPs, ranges, analytics, and supply plan, and after a facility fit check.
What are the top kill switches.
Irreproducible TRY, DSP cost dominance, no customer validation path, and unhedgeable single-source inputs.
Conclusion
Biomanufacturing only works at scale when product clarity, process reproducibility, and unit economics converge, and the David Friedberg checklist helps you force that convergence before you spend big.
Use this readiness checklist to align your fermentation, downstream, COGS, and financing strategy, and you’ll move from lab to scale with fewer surprises and stronger leverage with partners and investors.
If you remember one thing, it’s this: measure what matters, run the hard scale-down model, and let the numbers tell you when you’re ready to scale like David Friedberg would insist.
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