I also think so. It is possible, depending the nature of the manuscript. However, a subtitle would be better, I think. The reason is that "secondary" gives readers (including editors and reviewers) a signal that the manuscript addresses a relatively less important issue.
for example, if your research is mainly about hemodialysis patients and their hypertension management (this is the main objective and you have certain outcomes to achieve your objective)
Secondary objective, you investigated whether they have depression or not
The effectiveness of hypertension management among hemodialysis patientsㅡI think that it is enough! You no longer need to think about how to incorporate the secondary objective into the Title.