There’s new life for the long-stalled Midtown development site at 520 Fifth Ave., at East 43rd Street.

Rabina Properties just closed on a joint-venture partnership for the vacant corner lot in which it will take over the driver’s seat from Ceruzzi Properties and SMI, The Post has learned.

The 800-foot-tall tower will have more office space and less retail than originally planned, sources said.

The lot has been a vacant eyesore for several years. Ceruzzi and SMI had planned to build a tall and slender skyscraper, but the project stalled.

Partner Louis Ceruzzi’s death in September 2017 further delayed things.

Now, sources say, major-league New York developer Rabina has formally bought into the project in a deal described as a partnership restructuring and recapitalization.

Ceruzzi and SMI will remain part of the development team.

The agreement with Rabina was first reported in May by the Real Deal — but the deal wasn’t final until Monday.

Marcus & Millichap’s Eric Anton, who was said by sources to have brokered the joint-venture transaction, declined to comment.

A $232 million loan on the property to Mack Real Estate, which was in default, has been paid off as part of the new transaction and will be replaced with a new loan, sources said.

The empty lot at one of the city’s most valuable locations has long perplexed passersby as well as real estate insiders.

The roughly $600 million project is expected to differ somewhat from the original design. The tall, slender tower of 400,000 square feet will have lower-level retail but less than first planned; about 170,000 square feet of office space; and luxury apartments at the top.