I have a working formula and proof of concept product that has been (unscientifically) tested on individuals with sleep problems and insomnia over a 10 year period. 100% of those who have taken it says it worked for them. 100% naturally based.
Having worked for both industries for a decade I can tell you that no pharmaceutical company is going to be interested in doing your research for you. And depending on their ethics, very few supplement companies are interested in outside product ideas, considering there is rarely any product that can be protected from competition. That "proprietary blend" might discourage others from copying the formulation exactly, but it also significantly decreases credibility with the consumer.
Anecdotal evidence (non-scientific feedback) will not build credibility for your product, not in the way that will make you a success. You have chosen one of the two most popular areas for consumers, things that address pain issues and things that address sleep issues. But without scientific evidence, your product is a "me too" product. Since no supplement can make a health claim without being a drug, you're left with anecdotes. That's generally not something worth investing in to most people.
If it really works, repeatably, then it warrants scientific study to verify. That's not cheap or fast and doesn't guarantee you can protect yourself from copycats though, which is why you never see non-governmental research on products anyone can bottle (vitamins and supplements). It's too expensive for private companies to research products that can't be protected with patents. And while you could spend the next decade trying to work with a governmental research program that would support your efforts in treating sleep disorders, that will not lead you to monetary fortune.
Unfortunately, that's just how the business works.
How many constitute 100%? Hate to say it, but even if that is/were true, you are going to hurt yourself stating it works 100% of the time, because there is not any drug or medicine on the market that achieves that...except water.