OnCo
bottlenecksBottleneck

Preclinical models that do not predict people

Nine in ten cancer drugs that work in mice fail in humans. Our models are the reason.

Oncology has the lowest probability of success of any therapeutic area: only a few percent of agents entering phase 1 reach approval, and most failures are for lack of efficacy that the preclinical package did not anticipate. Immortalised cell lines have drifted for decades and lack a microenvironment; subcutaneous xenografts grow in immunodeficient mice with no human immune system, stroma or metastatic pattern; genetically engineered mouse tumours evolve with far less heterogeneity than human disease; and patient-derived organoids capture epithelial biology but not vessels, immune cells or drug pharmacokinetics. Preclinical studies are also small, unblinded and rarely replicated. The result is a pipeline that spends billions in humans to learn what the models could not tell it. Better-validated models, functional testing on fresh patient tissue, and systematic benchmarking of model predictions against clinical outcomes are the fixes.

criticalbiology54 ideas to fix it
How big the problem is
3.4%
Probability that an oncology drug entering phase 1 is eventually approved
6.7%
Oncology likelihood of approval from phase 1 (industry data 2003-2011), lowest of all disease areas
6 of 53 (11%)
Landmark preclinical cancer papers whose findings Amgen scientists could reproduce
Root causes
  • Cell lines have adapted to plastic for decades and no longer resemble the tumours they came from.
  • Xenografts require immunodeficient hosts, so anything involving the immune system is invisible.
  • Mouse tumours are clonally simpler and are treated when small, which overstates drug effect.
  • Organoids lack stroma, vasculature and immune cells, and organoid drug exposure is not human pharmacokinetics.
  • Preclinical efficacy studies are small, unblinded, unregistered and rarely include controls that match clinical practice.
  • There is no systematic scoring of which models predicted which clinical results, so the field cannot learn which models to trust.
What is already being tried
  • The Human Cancer Models Initiative (NCI, Cancer Research UK, Wellcome Sanger, Hubrecht) and the PDCM Finder catalogue next-generation organoid and PDX models with clinical annotation.
  • DepMap (Broad Institute) systematically maps genetic dependencies across more than a thousand cell lines to separate robust from model-specific findings.
  • Champions Oncology, Xilis and cureSponse run functional drug testing on patient-derived xenografts, micro-organospheres and ex vivo tumour explants, with prospective studies comparing model prediction to patient response.
  • The NCI Patient-Derived Models Repository distributes clinically annotated PDX and organoid models.
  • Humanised-mouse and immune-competent organoid co-culture systems are being developed to test immunotherapies preclinically.
  • The FDA Modernization Act 2.0 (2022) removed the statutory requirement for animal testing, opening the door for validated human-cell and computational models.
What breaking it looks like
A drug that clears a defined preclinical panel has a documented, prospectively measured probability of clinical efficacy well above today's few percent, and functional testing on a patient's own tumour cells is validated to predict that patient's response.

Ideas to fix it

54top
preclinical evidenceengineeringmedium cost
A bone marrow niche on a chip to study human dormancy

Dormant cancer cells hide in bone marrow. A lab-built model of that hiding place would let us watch them sleep and wake, and test drugs on them.

speculativeengineeringsmall cost
A digital passport for every cell culture: identity, contamination status, passage number

Each batch of cells used in an experiment would carry a small digital record showing when it was authenticated, tested for contamination, and how many times it had been grown, attached to the published result.

preclinical evidenceresearchmedium cost
A drug screen that only rewards killing sleeping cancer cells

Nearly all cancer drugs are found by killing fast-growing cells. Sleeping cells survive them. A screen designed around dormant cells would find a different class of drug.

preclinical evidenceresearchmedium cost
A funded organoid and PDX panel as the go/no-go gate before IND-enabling money

Before any academic compound gets money for pre-trial studies, it would have to show activity in a standard panel of patient-derived tumour models run by an independent centre, so weak candidates are stopped early.

early clinicalphilanthropylarge cost
A global rapid tissue donation network for metastatic disease

Almost all cancer deaths are caused by spread, yet very little spread tissue is ever studied. A network collecting donated tissue within hours of death would change that.

speculativephilanthropysmall cost
A home for the animal and organoid experiments that failed

Failed laboratory experiments are rarely published, so other teams repeat them. A searchable place to deposit them would save years of duplicated work.

early clinicalresearchmedium cost
A phase 0 fund to test academic compounds in humans with microdoses and imaging

Before investing in a full trial, give a few patients a tiny dose of a new compound and use scans and blood tests to see whether it reaches the tumour and hits its target. Fund these small studies as a matter of routine.

preclinical evidencephilanthropylarge cost
A public atlas of drug-pair responses across a thousand patient-derived organoids

Build a large, openly shared dataset of how tumour organoids respond to drug pairs, so that anyone can look up which combinations might work for which tumour type.

speculativedatamedium cost
A virtual cancer cell that predicts what a drug will do before you test it

Train a model on millions of experiments where genes and drugs were altered, so it can predict the effect of a new combination without running the experiment.

preclinical evidencedatamedium cost
An open engine that ranks every drug pair by predicted synergy before anyone runs a trial

Use existing cell-line and organoid data to score thousands of drug pairs, publish the ranking openly, and only test the top of the list in people.

preclinical evidencephilanthropylarge cost
An open foundation model of the cancer cell trained on perturbation data

Build a shared, openly available AI model that has learned how cancer cells respond to genetic and drug perturbations, so any lab can predict what a new drug or combination might do.

preclinical evidencephilanthropymedium cost
An open model bank for the rare tumours nobody has models for

You cannot study a cancer without a laboratory model of it, and most rare cancers have none. A funded bank that makes and shares models would unlock research.

preclinical evidenceresearchlarge cost
An open model of every cancer cell state, built from perturbation atlases

Map every state a cancer cell can be in, and how drugs and the surrounding tissue move it between states, into an open computational model anyone can query and improve.

preclinical evidencephilanthropymedium cost
An open organoid bank for cancers too rare to have models

For many rare cancers there is not a single laboratory model in the world, so no one can test drugs. A shared bank with free distribution would change that.

early clinicalphilanthropysmall cost
Audit animal studies for randomisation and blinding, published by institution

Most mouse studies of cancer drugs do not randomise animals or blind the people measuring tumours, which inflates results. Checking and publishing which institutions do it properly would change behaviour.

preclinical evidenceresearchlarge cost
Automated combination discovery: patient-sample screens feeding Bayesian platform trials

There are far more possible drug combinations than can ever be tried in patients. Test thousands on living samples of real tumours, then feed only the winners into adaptive trials.

preclinical evidenceresearchmedium cost
Barcode patient-derived tumours to watch which clones win under each drug

Tag every cell in a patient's lab-grown tumour with a unique DNA label, give it a drug, and read the labels to see which cells survive. This predicts which resistant clone will emerge.

preclinical evidenceengineeringmedium cost
Build a human model of the barrier that guards the brain fluid

Drugs that reach brain tissue may still fail to reach the fluid where cancer spreads along the linings. A lab model of that second barrier would let us screen for drugs that cross it.

speculativeengineeringmedium cost
Build laboratory models of the organs cancer spreads to

Cancer usually kills by spreading to bone, liver, lung or brain. Almost all laboratory models grow tumours under the skin instead, where the surroundings are nothing like those organs.

speculativeresearchsmall cost
Every drug screen includes standard reference compounds whose performance is published

Labs testing new cancer compounds should always include a few well-known drugs as controls and report how those behaved, so results from different labs can be compared.

speculativeresearchmedium cost
Every resistance mechanism found in a patient must be rebuilt in the laboratory

When doctors discover how a tumour escaped a drug, that finding usually stops at a paper. Recreating it in a model gives everyone a system to test the next drug against.

preclinical evidenceresearchmedium cost
Grow blood-borne tumour cells to test drugs on the cells that actually spread

Drug tests normally use cells from the original tumour. Growing the rarer cells found in blood would test drugs against the cells that are actually travelling.

preclinical evidenceresearchmedium cost
Grow each trial patient's tumour as organoids to decide which platform arm opens next

While patients are treated in a platform trial, their tumour cells grow in a dish and are tested against dozens of drug pairs. The pairs that win in the dish become the next arms.

preclinical evidenceresearchmedium cost
Grow models from tumour cells in the blood when a biopsy is impossible

Some patients cannot have their tumour biopsied safely. Cancer cells captured from a blood sample can sometimes be grown into a model instead.

preclinical evidenceresearchmedium cost
Grow tumour organoids together with the patient's own immune cells

Lab-grown mini-tumours usually contain only cancer cells. Adding the patient's own immune cells lets researchers test immunotherapy outside the body.

preclinical evidenceregulatorsmall cost
Hold organoid drug tests to the same standard as a diagnostic test

Lab-grown mini-tumours are already being sold to guide treatment, but the tests are not validated like other medical tests. They should be.

preclinical evidenceresearchmedium cost
Humanised mice with an immune system matched to the tumour donor

Most cancer drugs are tested in mice with no immune system, then given to people who have one. Mice carrying the same patient's immune cells and tumour would be a fairer test.

early clinicalengineeringmedium cost
Implant a tiny device that tests twenty drugs inside the patient's own tumour

A rice-grain-sized implant can release small doses of many different drugs into separate spots of a tumour, then be removed so doctors can see which one worked in that person.

speculativeregulatorsmall cost
In silico trials to choose the dose before the first patient

Simulating thousands of virtual patients on a computer can suggest which dose and schedule to test, so fewer real patients receive doses that are too high or too low.

speculativeengineeringmedium cost
Keep a freshly removed tumour alive on a pump and test drugs in it

After surgery, a tumour with its blood vessels can be connected to a pump and kept alive for hours or days, allowing drugs to be tested in genuinely human tissue.

preclinical evidenceengineeringmedium cost
Linked human organ chips to predict side effects before people are dosed

Damage to the lungs, heart or liver is a common reason cancer drugs fail. Connected chips of human tissue may spot this earlier than animal tests.

preclinical evidenceresearchsmall cost
Make bespoke mouse cancer models in weeks with in vivo gene editing

Building a genetically engineered mouse for a specific cancer takes years. Editing genes directly in an adult mouse's organ can produce the same tumour in weeks.

preclinical evidenceresearchsmall cost
Make in vivo metastasis screens a required step in drug discovery

Drug candidates are tested for shrinking tumours, almost never for stopping spread. A standard spread test would find anti-metastatic drugs we are throwing away.

preclinical evidencephilanthropymedium cost
Multi-centre randomised animal trials before committing to a human trial

A drug that works in one laboratory's mice often fails elsewhere. Running the key animal study across several independent laboratories first would catch this.

early clinicalresearchmedium cost
Multi-laboratory preclinical trials as the standard for go/no-go decisions

Instead of one lab's mouse study deciding whether a drug goes to patients, several labs run the same protocol independently, like a multi-centre clinical trial for mice.

early clinicalresearchmedium cost
Pet dogs with spontaneous cancer as a bridge before human trials

Dogs get cancers that closely resemble human ones, with real immune systems and years of natural history. Treating them, with owner consent, can test drugs in a way mice cannot.

speculativedatasmall cost
Pick the laboratory model that matches the patient, not the one to hand

Labs usually use whichever tumour models they already have. A searchable index that finds the model closest to a specific patient's tumour would make experiments more relevant.

speculativepolicysmall cost
Pre-register animal efficacy studies like clinical trials

Clinical trials must be registered before they start so that failures cannot be hidden. Animal studies used to justify human trials should follow the same rule.

early clinicalpolicysmall cost
Pre-specified sample sizes for animal studies; no more 'representative' experiments

Many mouse experiments use so few animals that the results are unreliable, and papers show one 'representative' result out of several tries. Funders should require proper sample-size planning.

preclinical evidencepolicysmall cost
Prove the cell line is what you say it is, or the paper does not run

A troubling share of published cancer experiments use cell lines that are contaminated or mislabelled. Requiring a simple identity check before publication would stop this.

early clinicalpolicysmall cost
Prove your cell lines are what you say they are, or the paper is not published

A large share of cancer research has been done on cells that were mislabelled or contaminated. A cheap DNA fingerprint test can prove identity; journals and funders should require it.

early clinicalresearchmedium cost
Run the mouse or organoid trial at the same time as the human trial

Instead of testing a drug in lab models first and hoping the results carry over, build the same models from trial participants and run both experiments in parallel to see how well the models predict.

speculativedatasmall cost
Score every model system on how well it predicted real trial results

No one keeps score of which laboratory models actually predicted what happened in patients. A public scoreboard would show which models to trust.

speculativedatasmall cost
Score every preclinical model by how often it predicted the clinical result

For each type of laboratory model, keep a public record of how often its predictions came true in patients, so that researchers know which models to trust for which question.

preclinical evidenceengineeringlarge cost
Self-driving laboratories that run the cancer biology hypothesis loop autonomously

Robotic labs guided by AI that design experiments on tumour models, run them, read the results and design the next ones, around the clock, with every result published openly.

preclinical evidencephilanthropymedium cost
Shared reference organoid and PDX panels that every lab can test against

If every lab had access to the same set of well-characterised tumour models, results could be compared directly instead of each lab using its own private models.

preclinical evidenceresearchmedium cost
Test cancer drugs in old and unhealthy animals, not just young fit ones

Most cancer patients are older and have other illnesses, but nearly all animal experiments use young healthy mice. Results may not transfer.

preclinical evidenceresearchsmall cost
Test drugs on freshly cut slices of the patient's own tumour

A thin slice of a tumour, kept alive for a few days, still contains the immune cells and scaffolding that lab-grown cells lose. Drugs can be tested on it directly.

early clinicalclinicmedium cost
Test drugs on the patient's own cancer cells when there is no trial to join

For very rare cancers there is often no genetic clue and no trial. Growing the patient's cells and testing drugs on them directly can suggest what to try.

preclinical evidenceengineeringsmall cost
Tumour-on-a-chip with blood flow to test whether big drugs actually get in

Large drugs such as antibody-drug conjugates must cross vessel walls and travel through dense tissue. A chip with flowing channels and human tissue can measure how far they get.

early clinicalresearchmedium cost
Two-week pre-operative windows to compare combination biology head to head

Give patients a short course of one of several drug pairs in the gap before surgery and compare what happened inside the tumours. It is the fastest human test of whether a combination does anything.

speculativeresearchmedium cost
Use patient organoids to check a cell therapy will work before infusing it

Cell therapies are tested for purity and count, but not for whether they can actually kill that patient's tumour. Testing them against the patient's own mini-tumour would show this.

speculativeresearchlarge cost
Whole-patient digital twins validated in prospective randomised trials

Build a computer model of each patient's cancer and body that simulates how different treatments would go, and prove in a proper trial that choosing treatment with the model helps.

preclinical evidenceresearchsmall cost
Zebrafish avatars for a drug answer within a week

Tumour cells injected into transparent fish embryos grow in days, so several drugs can be compared in about a week, fast enough to help a patient who cannot wait.

Key papers

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Connected

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cancers

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fronts

1

technologies

6

companies

5

institutions

15

ideas

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A bone marrow niche on a chip to study human dormancyA digital passport for every cell culture: identity, contamination status, passage numberA drug screen that only rewards killing sleeping cancer cellsA funded organoid and PDX panel as the go/no-go gate before IND-enabling moneyA global rapid tissue donation network for metastatic diseaseA home for the animal and organoid experiments that failedA phase 0 fund to test academic compounds in humans with microdoses and imagingA public atlas of drug-pair responses across a thousand patient-derived organoidsA virtual cancer cell that predicts what a drug will do before you test itAn open engine that ranks every drug pair by predicted synergy before anyone runs a trialAn open foundation model of the cancer cell trained on perturbation dataAn open model bank for the rare tumours nobody has models forAn open model of every cancer cell state, built from perturbation atlasesAn open organoid bank for cancers too rare to have modelsAudit animal studies for randomisation and blinding, published by institutionAutomated combination discovery: patient-sample screens feeding Bayesian platform trialsBarcode patient-derived tumours to watch which clones win under each drugBuild a human model of the barrier that guards the brain fluidBuild laboratory models of the organs cancer spreads toEvery drug screen includes standard reference compounds whose performance is publishedEvery resistance mechanism found in a patient must be rebuilt in the laboratoryGrow blood-borne tumour cells to test drugs on the cells that actually spreadGrow each trial patient's tumour as organoids to decide which platform arm opens nextGrow models from tumour cells in the blood when a biopsy is impossibleGrow tumour organoids together with the patient's own immune cellsHold organoid drug tests to the same standard as a diagnostic testHumanised mice with an immune system matched to the tumour donorImplant a tiny device that tests twenty drugs inside the patient's own tumourIn silico trials to choose the dose before the first patientKeep a freshly removed tumour alive on a pump and test drugs in itLinked human organ chips to predict side effects before people are dosedMake bespoke mouse cancer models in weeks with in vivo gene editingMake in vivo metastasis screens a required step in drug discoveryMulti-centre randomised animal trials before committing to a human trialMulti-laboratory preclinical trials as the standard for go/no-go decisionsPatient-derived organoids to pick ADC payloadsPet dogs with spontaneous cancer as a bridge before human trialsPick the laboratory model that matches the patient, not the one to handPre-register animal efficacy studies like clinical trialsPre-specified sample sizes for animal studies; no more 'representative' experimentsProve the cell line is what you say it is, or the paper does not runProve your cell lines are what you say they are, or the paper is not publishedRun the mouse or organoid trial at the same time as the human trialScore every model system on how well it predicted real trial resultsScore every preclinical model by how often it predicted the clinical resultSelf-driving laboratories that run the cancer biology hypothesis loop autonomouslyShared reference organoid and PDX panels that every lab can test againstTest cancer drugs in old and unhealthy animals, not just young fit onesTest drugs on freshly cut slices of the patient's own tumourTest drugs on the patient's own cancer cells when there is no trial to joinTumour-on-a-chip with blood flow to test whether big drugs actually get inTwo-week pre-operative windows to compare combination biology head to headUse patient organoids to check a cell therapy will work before infusing itWhole-patient digital twins validated in prospective randomised trialsZebrafish avatars for a drug answer within a week

collections

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key papers

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