* Professional doctorates: Some professional doctorates, like a Doctor of Medicine (MD) or Doctor of Pharmacy (PharmD), have specific prerequisites that might not strictly require a bachelor's degree, but usually involve extensive pre-professional coursework and may require a substantial number of college credits. Essentially, the equivalent of a bachelor's degree is expected.
* Very rare cases: In extremely rare circumstances, individuals with exceptional experience and accomplishments might be granted admission to a doctoral program without a bachelor's degree, but this is exceptionally uncommon and usually requires significant evidence of readiness for doctoral-level work.
In almost all practical scenarios, you should assume that a bachelor's degree is a mandatory prerequisite for a doctoral degree.