A satellite view of Portsmouth. Image courtesy of Google Maps.

A Portsmouth-based subsidiary of an Israeli biotech firm is expanding its presence in the city with a new lease. 

Novocure signed a sublease for 19,000 square feet of class A office space at 135 Commerce Way. The company now leases a total of 54,000 square feet in two buildings at the Portsmouth Office Park, according to Colliers International. 

David Choate of Colliers’ Portsmouth office represented Novocure and Joe Doyle of CRESA Partners of Boston represented the sublessor, Liberty Mutual. 

Novocure is an oncology company developing a profoundly different cancer treatment utilizing a proprietary therapy called Tumor Treating Fields, which uses electric fields tuned to specific frequencies to disrupt solid tumor cancer cell division.  

The newly leased space in Portsmouth expands Novocure’s U.S. operations center. The company has hired over 150 local employees since it first relocated to 195 Commerce Way in Portsmouth in December 2011. 

Mike Ambrogi, Novocure’s chief operating officer, said in a statement that Novocure chose to expand again in Portsmouth because the city offers employees a great quality of life while providing access to the robust Greater Boston life sciences community.