Bioequivalence study of Vitamin D3 Pharma Patent 20,000 IU and the Vigantol 20,000 IU oral drops solutions and assessment of bioavailability in healthy volunteers
Vitamin D is essential for keeping our bones, teeth, and muscles healthy. This study is testing two different liquid forms of high-dose vitamin D3: an established medicine called Vigantol and a newer version made by Pharma Patent. Both treatments contain 20,000 IU of vitamin D3. Researchers want to see if both brands are 'bioequivalent'. This means checking whether the active vitamin enters the bloodstream at the same speed and in the same amount. Proving this ensures that patients can safely use either brand with the exact same health benefits. To test this, healthy adult volunteers aged 18 and over will take single doses of each liquid medicine at different times. Doctors will take regular blood samples to measure vitamin levels. Taking part is entirely voluntary, and participants can change their mind and withdraw at any time.
At a glance
What is this study about?
Vitamin D plays a vital role in our everyday wellbeing, particularly for bone strength and immune function. In the UK, many people do not get enough vitamin D from sunlight alone, and doctors sometimes prescribe strong, concentrated drops to treat or prevent low levels. When a company develops an alternative version of an existing medicine, regulations require them to prove it performs identically to the original.
This trial focuses on comparing two oral drop solutions that each contain 20,000 International Units (IU) of vitamin D3: an existing medicine named Vigantol and a new version by Pharma Patent. The main aim is to assess 'bioavailability'—which simply means how much of the vitamin reaches your bloodstream and how fast it gets there.
Because this is a Phase I bioequivalence study, it is carried out in healthy volunteers rather than people with medical conditions. This allows scientists to see how the human body naturally processes the medicine without interference from illnesses or other regular treatments.
If the study shows that both medicines behave the same way, regulators and healthcare providers can approve the newer product. This gives doctors and the NHS more choices, helps prevent medicine shortages, and can help lower healthcare costs while maintaining the same high standard of patient care.
Key takeaways
- Tests whether two brands of vitamin D3 oral drops work identically in the body.
- Aimed at healthy volunteers aged 18 and older.
- Involves taking single doses of liquid drops followed by blood tests to measure absorption.
- Helps support new, safe treatment options for the NHS and patients.
- Participation is completely voluntary, and you can withdraw at any time.
Who may be eligible?
This trial is designed for healthy adult volunteers aged 18 and over. Men and women can both apply. Because researchers need to track the medicine cleanly, they look for people who are in good general health and do not have ongoing illnesses.
You are unlikely to be eligible if you have medical issues that affect how your body absorbs nutrients, such as serious bowel or digestive conditions. People with kidney disease or high calcium levels in their blood will also be excluded, as very high doses of vitamin D might not be safe for them.
You may also need to avoid taking other vitamin D supplements or certain over-the-counter medicines in the weeks leading up to the study. The research team will run health checks, including routine blood and urine tests, to make sure taking part is completely safe for you.
Could this study suit you?
Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.
- I am aged 18 or over.
- I consider myself to be in good overall health.
- I do not have a history of kidney disease or high blood calcium.
- I am willing to attend clinic visits and give blood samples.
- I can pause taking over-the-counter vitamin supplements if asked by the study team.
What does participation involve?
Taking part usually begins with a screening visit where the medical team checks your health, medical history, and blood tests to confirm you can safely join. If eligible, you will attend the clinic to receive the study medicines. Most bioequivalence studies use a 'crossover' design: you will take one brand of drops on one visit, and the other brand on a later visit after a rest period known as a 'washout'. During clinic visits, you will swallow a measured dose of the drops with water. The team will then take small blood samples at set times over several hours or days to track how vitamin D rises and falls in your body. The whole study, including screening, dosing days, and a final check-up, typically lasts a few weeks.
Potential risks and benefits
Locations (1)
- —UnverifiedHungary
Common questions
What does bioequivalence mean?
It means two medicines contain the same active ingredient and are absorbed by the body at the same speed and amount, making them work in the same way.
Why is the study done on healthy people instead of patients?
Testing in healthy volunteers allows scientists to see how the body handles the medicine on its own, without symptoms or other drugs affecting the results.
Is 20,000 IU of vitamin D dangerous?
No, this is a standard high-dose medical treatment often prescribed by doctors for short-term use, and it is considered safe for healthy adults.
Will I have to stay overnight at the clinic?
Some bioequivalence studies require a short day stay or an overnight visit to take blood samples on time. The study team will explain the exact schedule beforehand.
Can I leave the study if I change my mind?
Yes. You have the legal right to stop taking part at any point, and your decision will not affect any future medical care.
How to find out more
Always speak to your GP or specialist before deciding to take part in a study.
Discussion
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