The present invention provides new stable packaging cell lines and producer cell lines as well as methods to obtain them, and a new method to produce lentiviral vectors using such cell lines. New methods and packaging cell lines of the invention are generated using a baculo-AAV hybrid system for stable expression of structural and regulatory lentiviral proteins, such system comprising a baculoviral backbone containing an integration cassette flanked by AAV ITR, in combination with a plasmid encoding rep protein. This system allows to obtain a stable integration of the structural and regulatory HIV-1 proteins gag/pol and rev. The system allows to obtain a first intermediate including only the structural and regulatory HIV proteins gag/pol and rev, to be used as starting point to obtain stable packaging cell lines as well as producer cell lines.