Your question is imprecise.
Do you mean did anyone get accepted without a bachelor's degree, generically speaking?
Or do you mean did anyone get in without, specifically a Bachelor of Science degree?
If the latter, a BS degree is not mandatory: any bachelor's degree and any major will do as long as the required premed courses courses are included. The NAME of the degree is irrelevant.
In the former case, students MAY get accepted with a minimum (usually) of 90 credits on the open market. However, most students who get accepted without bacccalaureates do so through special programs at colleges having a contractual agreement with a medical school.
For example, Chapter 9 in the Medical School
Admissions Requirements (MSAR) has a list of medical schools offering combined College/MD
programs for high school students. There are 6 year, 6-7 year, 7 year, 8 year programs. The 6 and 7 year programs admit students to the medical school after 2 or 3 college years, without a degree; some colleges award the bachelor's degree upon completion of the first year of medical school.
These programs are contracts between specific undergraduate institutions and specific medical schools. Commonly, students are selected for these programs during their senior year of high school and enroll in the participating college or colleges.
Two examples are the Boston University/BU Medical school program and Michigan State University/MSU College of Medicine.
There are many other contractual arrangments between a college or colleges and one or more medical schools that do not appear on the MSAR high school/college/MD programs list. Such arrangements will be mentioned in the undergraduate bulletin of colleges that have them.
Not related to the question are frequent arrangements between postbaccalaureate programs and one or more medical schools.
Statistically speaking, expect to earn a baccalaureate degree before matriculating in a medical school.
