I know of only one major medical school with a MCAT loophole. Wake Forest has an Early Assurance Program for applicants who have completed two years of undergraduate work. I learned about it last year, but I decided not to apply for it since frankly, I did not qualify. Their website states:
"Well-qualified college students, upon completion of the sophomore year, at very competitive schools may apply for acceptance to the class entering two years later. Eligibility requires a minimum GPA of 3.5 each semester for the science, non-science and overall GPAs and completion of half of the required prerequisites. THE MCAT WILL NOT BE REQUIRED.
A student applies early in the junior year through the AMCAS process (November 1 deadline), asking consideration for the EAP. The applicant must agree to complete requisite courses, to continue academic excellence, to demonstrate high ethical conduct and not to apply to any other medical school. Non-acceptance by the EAP does not influence future applications. The EAP should not be confused with the Early Decision Program."
I called the admissions office to see if this really meant no MCAT requirement and it does mean just that. In fact , they accepted a Wake Forest ungrad last year with no MCAT score (he/she must have cured cancer !!). However, per the admissions officer, very few applicants are accepted on this basis (1 or 2 per year at most), and the person from admissions charactized it as an "extremely" competitive program. She said there have been a few years when nobody was accepted under this Early Assurance Program, even with MCAT scores provided.