As mentioned before, an unsecured loan will probably have a higher interest rate than secured loans of the same or similar value. This is because lenders want to minimise risk, and without a security, they stand to lose a lot should their borrowers default. High interest rates cushion the blow for lenders.
Note that a high interest rate doesn't necessarily equate to a high comparison rate. On top of the interest rate, the comparison rate also accounts for fees and charges. So a loan with a high interest rate and low fees and charges can have the same or even lower comparison rate than a loan with a low interest rate but high fees and charges.