Headlines buzzed about azelastine, a simple allergy spray that showed promise in cutting COVID infections.

That’s the magic of drug repurposing:

 Take an old medicine, give it a new job, and skip years of costly R&D.

But here’s the truth no one puts on the slide deck:
Repurposing only works if toxicology is in the driver’s seat.

 The Sports Car Analogy

A car tested on city streets isn’t automatically safe for a mountain road.
Same machine, new context.

Without guardrails, you’re gambling.
That’s exactly what happens when you repurpose a drug.

 Why Toxicology Matters

Changing the “what for” changes the risk:

An allergy spray safe for spring may be unsafe used daily for months.

A drug tested in healthy adults may act differently in seniors, kids, or pregnant women.

New doses or delivery routes can unlock hidden side effects.

 Toxicology = Your Secret Advantage

 Leverage what’s known – decades of safety data already exist.

 Stress-test the new scenario – longer use, higher dose, vulnerable populations.

 Spot off-target risks – toxicologists read PK/PD like radar.

 Shape trial design – anticipate safety questions before regulators ask.

 FDA guidance is crystal clear: change the use, dose, or delivery, and you must revisit safety. Founders who plan for this early move faster, spend less, and avoid costly failures.

 Why Investors Should Care

For investors, toxicology isn’t overhead—it’s risk insurance.

Derisks portfolios by filtering out weak bets before late-stage collapse.

Makes companies funding-ready, proving safety is more than an afterthought.

Turns hype into durable value.

 The Takeaway

Repurposing is the shortcut.
Toxicology is the guardrail.
Together, they turn old drugs into winning new products.

#DrugRepurposing #BiotechFounders #LifeScienceInnovation #Toxicology #FDA #HealthcareStartups #BiotechInvestment #MedTech #DrugDevelopment #HealthInnovation

References & Further Reading
Azelastine nasal spray reduced COVID-19 infections in a 56-day Phase II trial – JAMA Internal Medicine: https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2798656

Azelastine overview and safety profile – Verywell Health: https://www.verywellhealth.com/azelastine-uses-side-effects-dosage-4766858

FDA Clinical Review of Azelastine – FDA: https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/020114s023,020815s020lbl.pdf

Nonclinical Safety Evaluation of Reformulated Drug Products and Products Intended for Administration by an Alternate Route – FDA Guidance: https://www.fda.gov/media/119657/download

M3(R2) Nonclinical Safety Studies for the Conduct of Human Clinical Trials and Marketing Authorization – ICH/FDA: https://www.fda.gov/media/71542/download

Repurposed Drugs and COVID-19: Lessons and Limitations – Frontiers in Pharmacology: https://www.frontiersin.org/articles/10.3389/fphar.2021.649887/full