These are really two possibilities, depending on your context. Generally, I understand your term as having a negative connotation -- which 'inside track' has -- implying unfair privilege due to connections or wealth.

But in corporate or organisational contexts I've seen the Swe sometimes (more or less incorrectly) used much like 'fast track'. As in when people are hired to a 'fast track' managerial position to groom them for further advancement in the company.