Final answer:
The exclusion of patients on biologics from a phase 3 clinical trial depends on the specific study's protocol and objectives, which are not provided in the question, leading to the conclusion that there is not enough information to determine the answer.
Step-by-step explanation:
Whether patients on biologics will be excluded from a phase 3 clinical trial is not information that can be universally applied to all studies since inclusion and exclusion criteria are specific to each clinical study. Usually, these criteria are detailed in the study protocol, which is developed with regard to the study's objectives, the condition under investigation, and the safety of participants.
If a study aims to evaluate the efficacy of a new intervention in patients who are not currently receiving biologics, then those on biologics may be excluded. Conversely, if the study is meant to gauge the effectiveness of a combination of treatments or compare different treatments for patients already taking biologics, then such patients might be included.
Therefore, without specific information about the phase 3 study in question, the correct answer is D. Not enough information given to determine the answer.