Kevin George, DEXUS executive general manager office and industrial, said Roche will take up about 25 per cent of the space at 30 The Bond previously occupied by Lend Lease.

"We have been able to build on our existing relationship with Roche and capture the flight to quality that is under way in the Sydney office market." Roche will be relocating its head office from the Northern Beaches and is excited about the move to the Sydney CBD," Mr George said.

The deal was unveiled after DEXUS reported a statutory net profit for the year to June 30 of $1.3 billion, up 104 per cent on the previous corresponding period, driven primarily by revaluations.

In the results, the group said with a range of new leases in the pipeline, the new tech business tenants and the withdrawal of space for the Metro rail line, it is foreseeable, if not probable, the Sydney office vacancy rate will get below 4 per cent, if not 3 per cent, by 2019, and that will be the lowest vacancy rate for 15 years.

Funds from operations, the preferred measure of earnings by real estate investment trusts, were $610.8 million, up 12 per cent on the 2015 year, and was in line with market expectations.

For the year FFO per security was 63.1¢ and distribution per security was 43.51¢, both up 6 per cent on the 2015 year. The distribution will be paid on August 31.

The underlying FFO per security is forecast to grow 3-3.5 per cent, and distribution per security 2.5-3.5 per cent.

DEXUS, which made an unsuccessful tilt at Investa Office Fund late last year, focuses on the three core areas of office and logistics, property development and funds management.

One of the most active was the development division where the group has a pipeline of development opportunities during the next five years valued at $4.7 billion. One project is the planned office tower at 105 Phillip Street, Parramatta.

Due to some lease expiries the industrial business was lower than expected but the group said overall, the sector remained a strong business contributor.

DEXUS chief executive Darren Steinberg said four years ago the group reset its strategy to focus the business on Australian office property and third-party funds management.

"As a result, today we are Australia's largest office landlord with 1.8 million square metres of office space under management and have grown our third-party funds from $5.6 billion in 2012 to $11.2 billion," Mr Steinberg said.

The earnings were boosted by a range of asset sales such as the recent agreement to sell Southgate Complex, Melbourne, for a net sale price of $578 million, reflecting a 12 per cent premium to book value, to settle in two equal tranches in 2017 and 2018. It was bought by Singapore's Suntec REIT and ARA Asset Management.

Mr Steinberg said third-party funds under management increased to $11.2 billion, up 17 per cent from June 30, 2015, driven by acquisitions, developments and revaluations. He said the group was reviewing new funds, and this could involve owning medical assets such as the group's industrial site at 12 Frederick Street in  St Leonards adjoining the Royal North Shore Hospital that has been rezoned as a proposed mixed-use hospital precinct.

"We are not saying we are launching a fund today, but we are investigating it," he said.

The analysts at Macquarie Equities said the overall result was within 1 per cent of their forecast, "but the quality is better than we were expecting with operating earnings before interest and tax, pre-FFO adjustments, of $690 million was above our $677 million forecast, net property income, pre-amortisation add back, from the office portfolio was about 2 per cent above our expectation"

"The incentive amortisation and rental straight lining adjustment, that is the low-quality component of FFO, was lower than our forecast," the analysts said.