CBSET is rolling out big plans in Waltham, with a 110,000-square-foot laboratory and office complex slated for 153 Second Ave that the company says will roughly triple its preclinical capacity and double as a home base for foreign biotechs entering the U.S. market. The project is being developed with French auditory biotech Cilcare and follows a growth investment last year that CBSET said would bankroll larger facilities and add-on capabilities. Company leaders and state officials are pitching the site as a turnkey hub of lab, regulatory and office services designed to speed up hearing-science programs and other life science entrants.
New Waltham Site and Scope
According to the Boston Business Journal, CBSET plans to build a roughly 110,000-square-foot facility at 153 Second Ave in Waltham that is expected to triple the company's lab capacity. The article, published May 12, 2026, reports that the project is designed to create room for additional GLP-compliant labs and specialized testing suites for device and drug developers. The outlet notes that the announcement ranks as one of the larger suburban lab expansions along the Route 128 corridor this year.
Arlington Investment and Expansion
The Waltham build-out is directly tied to a majority growth investment in CBSET by Arlington Capital Partners announced in October 2025, which company leaders said provided the capital to scale facilities and pursue add-on capabilities. In a press release about the deal, executives at CBSET described Arlington's backing as a catalyst for "scaling the integrated preclinical research & testing platform." That same release framed the investment as setting the stage for the significantly larger Waltham project now on deck.
Cilcare Partnership and Clinical Tie
French biotech Cilcare, which has worked with CBSET since 2017 on preclinical auditory research, used the SelectUSA Investment Summit in early May to spotlight its U.S. push. At the event, the company announced a U.S. clinical trial of its tinnitus drug candidate at Massachusetts General Hospital and pointed to the expanded CBSET capacity as part of its growth story. Cilcare's expansion plans and the MGH trial were detailed in a member news post from MassBio.
A Gateway for Foreign Biotechs
Cilcare and CBSET say the Waltham site is intended to function as a turnkey gateway for international companies by offering lab benches, regulatory support and connections to local clinical and academic centers, a concept outlined in Cilcare's SelectUSA materials. A French press packet presented the project as part of a broader strategy to make Massachusetts a preferred landing pad for overseas life science firms, according to France-Biotech.
Waltham Real Estate Context
The move arrives as Waltham continues to turn older office buildings into lab-ready space. Newmark's Q3 2025 life science market report logged an 87,000-square-foot direct lease to CBSET at 153 Second Ave, underscoring the firm's growing footprint in the Route 128 market. The same report described a mix of office-to-lab conversions and select build-to-suit projects as suburban landlords chase lab tenants that have been priced out of Cambridge and Boston, according to Newmark Research.
Company and state officials have cast the Waltham project as both a capacity play for CBSET and a tool to strengthen the regional ecosystem for foreign biotechs. As Cilcare CEO Celia Belline described it, the partnership with CBSET is "a shared translational engine," according to MassBio. Local leaders say the expansion is expected to bring construction and lab jobs to Waltham and give overseas developers a quicker route into U.S. regulatory work, although a construction timetable and job estimates were not included in the initial announcements.
