Ennead Architects, the New York-based firm whose past projects include Philadelphia’s National Museum of American Jewish History, is designing a pale glass medical office tower for the yet-to-be redeveloped southern portion of the East Market project site in Center City.

The plans for the 23-story medical building — along with a 24-story (but shorter) tower with 396 dwelling units to be designed by Morris Adjmi Architects, also of New York — are scheduled to be reviewed Dec. 3 by Philadelphia’s Civic Design Review board.

The CDR panel offers nonbinding suggestions about the city’s biggest development proposals as part of the building-approval process.

National Real Estate Development, based in Washington, D.C., broke ground in 2014 on the East Market project, a planned $800 million development, on land it controls between 11th and 12th Streets on Market Street.

It is nearing completion of work on the Market Street-facing two-thirds of the property, where it has developed a pair of apartment towers and an office building, with lower-story spaces occupied by Iron Hill Brewery & Restaurant, TJ Maxx, Mom’s Organic Market, and other retailers.

It is also converting the historic Stephen Girard Building on 12th Street, between Market and Chestnut Streets, into a hotel under Hilton’s boutique Canopy brand.

The medical and residential towers to be designed by Ennead and Adjmi would rise on the Chestnut Street-facing portion of the site, where an art deco parking structure slated for demolition now stands.

It will be Adjmi’s third project at the East Market site, after the 1100 Ludlow office building and the Girard apartment building at 1199 Ludlow St.

Ennead’s other past projects include the Clinton Presidential Library in Little Rock, the Standard hotel straddling the High Line in New York, and the Newseum in Washington.