Healthpeak Properties is expanding its multimillion SF life sciences portfolio in Greater Boston by spending nearly three-quarters of a billion dollars for Cambridge Discovery Park in Alewife.

The developer closed on the 620K SF campus of three Class-A life sciences buildings on Acorn Park Drive for a gross sale price of $720M, sellers Harrison Street, Bulfinch Cos. and National Real Estate Advisors announced Monday.

The stretch of offices is a combined 94% leased, the sellers said. Tenants include biotechnology, pharmaceutical and research companies with a weighted average remaining lease term of approximately seven-and-a-half years, Healthpeak reported in its quarterly earnings last month.

"The successful sale of this portfolio demonstrates Harrison Street’s life sciences investing expertise and unwavering focus on creating value for our investors and partners,” Harrison Street Senior Managing Director and Head of Asset Management Ben Mohns said in a statement.

Bulfinch will manage the properties going forward and maintain an ownership stake, the sellers said in the release.

“We look forward to a long and mutually rewarding partnership that extends beyond CDP into additional life science and medical assets in Greater Boston," Bulfinch CEO Eric Schlager said.

Bulfinch, which has developed the site over the past two decades, said it looks forward to future development with Healthpeak at CDP to include an additional 100K SF.

Healthpeak didn't immediately respond to a request for comment but said it paid $664M for the majority stake in the building, valued at $720M. The transactions between Bulfinch and Healthpeak holding companies were dated in late October and published last week in South Middlesex County public records.

Healthpeak now claims a 2.4M SF portfolio in Greater Boston, including the $174M, 159K SF life sciences project at 101 CambridgePark Drive that broke ground in September, the developer said last month.

Big-money deals have boosted the West Cambridge market in 2020, proving it to be an alternative for life sciences players seeking opportunities outside of Kendall Square, which has a near-zero vacancy rate, according to CBRE’s Q3 2020 lab report.

Last month, Bulfinch acquired its 13th asset in Cambridge, a 7,200 SF facility in Harvard Square, for $5M. Chicago-Based Harrison Street last year bought Kendall Square’s Osborn Triangle for more than $1B, which touts tenants like coronavirus vaccine developer Pfizer.