One Milestone at Harvard ERC. Image courtesy of Henning Larsen and Studio Gang
Lab vacancies in Greater Boston hit 34 percent in the fourth quarter, but the pace of construction slowed as the region’s big development boom wanes.
Vacancies rose 5 percent in 2025, including 0.4 percent in the fourth quarter, Cushman & Wakefield reported.
Even industry epicenter Cambridge wasn’t immune to the weakness. Vacancies rose 2.2 percent in the fourth quarter, the largest of any submarket.
In a deal announced this week but completed during the fourth quarter, Genentech added 67,808 square feet at the Harvard Enterprise Research Campus in Allston. The transaction triples its space in the Tishman Speyer-Breakthrough Properties-developed lab building, Bisnow reported.
The Roche subsidiary signed on last March as the first tenant at the 440,000 square-foot development off Western Avenue, which is scheduled to open this year. The Roche Genentech Innovation Center will specialize in drug discovery in cardiovascular, renal and metabolic health.
In a deal announced in January, TransMedics’ lease of an entire building in Assembly Square gave a boost to the struggling Urban Ring submarket, which ended 2025 with a 55 percent vacancy rate for its 11.3 million square-foot inventory.
Tenant demand is rebounding, pointing to a potential uptick in leasing activity in 2026. Cushman & Wakefield is tracking 2.1 million square feet in tenant requirements, up 72 percent from 2024.
Construction completions declined to 2 million square feet, with another 3.6 million square feet still in the pipeline. Completions peaked at over 6 million square feet in 2023.
Among large developments currently under construction, Alexandria Real Estate Equities’ 421 Park Drive in the Fenway will add 660,000 square feet. Two other major developments are preleased: BioMed Realty’s 585 Kendall St. will be occupied by Takeda, while AstraZeneca will occupy BXP’s 290 Binney St.
Average asking rents dropped 2.2 percent in the fourth quarter and 5.6 percent year-over-year to $78.96 per square foot. Cambridge led the discounting, with asking rents dropping $6.88 per square foot to $90.01.
