Excellent question! I've seen these issues firsthand (both myself using lean startup in my health 2.0 co., and with my clients) and I honestly don't feel there's a 'one size fits all' answer. Based on the info you've posted, I think you need to really understand what your main goal is. If it's for reversing disease, leave the B2B piece until you've worked the bugs out with your patient beta testers and make your product work best for them. Make it a great product. Get a community of users. Then bring to influencers and your potential B2B customers when it's working and has a user base that allows you to better demonstrate the value to that set of customers in the data, etc. Happy to chat further if you have other questions!