Yesterday, I presented the first two questions you need to ask when designing a clinical study. Now, without further ado, I present the last two.
3.) How many subjects are needed for the study to be adequately powered? A minimum requirement today for nutritional products is that the changes in the group taking the active dose must be significantly different than the changes in the placebo or control group. It makes no sense to design and invest in a study that will show no difference between your product and a sugar pill. For some subjective measures such as pain, the placebo effect and inter-individual variation can be very high, due to the subjective and ever-changing nature of pain perception. In this case, the number of subjects required to get reliable statistical separation between the active versus control groups is relatively high. For other endpoints, such as blood concentrations of actives in pharmacokinetic studies, placebo effects are almost nil, and therefore a lower ‘n’ is likely to result in significant changes versus controls.
4.) What is the budget and timeline? Research is an investment, one that can be expensive and time-consuming. For example, if the therapeutic area and endpoints include testing of blood markers, then the drawing, processing and testing of blood samples is a major cost center in the research budget. Common blood markers such as blood lipids are relatively easy using standard kits, while other less standard markers can require method development and increase costs, and may provide unreliable data that needs to be repeated.
A university-based study offers the independence and clout of world-class clinical studies, but the prestige can be balanced with increased costs and more uncertainty in the timeline, particularly when your study is relatively small and relies on shared resources. While a contract research organization is often faster than a university, this option can also come with greater costs. A research services contract with a detailed protocol and time-based milestones is critical to have in place.
Ethical approval (typically through an Institutional Review Board, or IRB) is also required for all human studies. Some research centers can get IRB approval within a month, while others are mired in bureaucracy and generally take six months or more.
Recruiting also contributes to the study timeline. If you are excluding a lot of lifestyle factors, then your available population is low, and getting the required number of subjects can be costly if not impossible. Many clinical studies never get off the ground when recruiting is not taken into account.
Lastly, it is critical to do the homework up front and ask a lot of questions. Make sure you have someone in your corner, who speaks the language and is looking out for your best interests. Only then can you ensure the returns on your research investment are maximized.