The accident happened just before 2:00 a.m. in the westbound lanes of the Vine Street entrance to the Schuylkill Expressway in Center City.
The vehicle's 32-year-old driver lost control and crashed into a guard rail. She was trapped and needed to be extricated by rescue workers.
The driver was rushed to the hospital in serious condition. Her 18-year-old male passenger suffered head and neck injuries and was taken to the hospital in stable condition.
There's no word on what caused the driver to lose control of the vehicle.