In more than a decade of working in preclinical research across pharma and CRO settings I have seen the same story play out many times. A compound that looks safe, effective, and full of promise in preclinical studies struggles to deliver once it enters clinical trials. For me, as a veterinarian and toxicologist, these moments are both humbling and instructive. They remind us that bridging preclinical and clinical gaps is not a box to be ticked; it is one of the most critical and nuanced challenges in drug development.
Why the Gap Persists
The preclinical-to-clinical transition is where scientific optimism often collides with biological complexity. Some of the recurring issues I have observed include:
- Model limitations: Even the most carefully chosen research models cannot replicate the full complexity of human disease.
- Endpoints that don’t translate: A biomarker or readout that is meaningful in preclinical studies may not have a clear analogue in clinical trials.
- Pharmacokinetics and dosing challenges: Converting safe and effective dose ranges from animals into the clinical setting is rarely straightforward.
- Regulatory nuances: Requirements shift depending on the product type whether small molecules, impurities, biosimilars, or medical devices and misalignment can create major delays.
- Siloed approaches: Too often, discovery scientists, toxicologists, and clinicians work in parallel rather than in true collaboration.
Strategies That Make a Difference
Over the years, I have found certain practices consistently improve translational success:
1. Designing with the End in Mind
Preclinical studies are strongest when they anticipate the needs of regulators and clinical trialists. The right questions, models, and endpoints must be chosen from the very start, not retrofitted later.
2. Refining and Validating Research Models
As a veterinarian, I’ve always valued the nuances of selecting the right model. Whether it’s choosing immunodeficient strains for oncology or refining toxicology models for medical devices, these choices determine how predictive our data will be for the clinic.
3. Translational Biomarkers
Biomarkers that carry meaning across both preclinical and clinical studies provide one of the most direct bridges between the two worlds. The closer the alignment, the lower the risk of surprises downstream.
4. PK/PD Integration
Robust pharmacokinetic and pharmacodynamic modelling built on carefully designed preclinical data offers a much more reliable foundation for dose selection in first-in-human studies.
5. Early Cross Functional Collaboration
The most successful translational programs are those where toxicologists, pharmacologists, clinicians, and regulatory experts work together from day one. When silos break down, insights align.
6. Balancing Tradition with Innovation
Research models remain the cornerstone of preclinical testing. But in my experience, they are most powerful when complemented with newer approaches whether organoids, computational models, or advanced imaging techniques. Integration, not replacement, is the key.
Lessons from Experience
Contributing to multiple IND filings has taught me that the translational gap is not a single obstacle but a series of decisions. Each decision about models, endpoints, dose levels, or regulatory strategy can either strengthen the bridge or widen the divide.
What I have learned is that success doesn’t lie in eliminating uncertainty (which is impossible), but in reducing it intelligently. Preclinical science must be rigorous, relevant, and forward looking if it is to serve as a reliable foundation for clinical development.
Looking Ahead
The future of translational science, in my view, will be shaped by balance. Balance between research models and new technologies. Balance between scientific ambition and regulatory discipline. Balance between speed and rigor.
For those of us working in preclinical research, the responsibility is enormous: to provide not just data, but evidence that can withstand the transition into clinical trials. Each study is a piece of that bridge and the stronger we make it, the closer we bring new therapies to the patients who need them.
Written by: Dr. Anil K. Gothi | GVSAP | Vice President & TFM
Anil is an M.V.Sc in Pharmacology and Toxicology, and a Board-Certified Toxicologist (DABT, ERT) with over 16 years of preclinical experience in pharma and CROs. He has contributed to multiple IND filings and has expertise across diverse product categories including impurities, biosimilars, and medical devices. He has extensive experience in regulatory requirements, global safety studies, and strategic operations for US and European clients.

