Pharmaceutical giant Glaxosmithkline (GSK) has finally completed its multibillion-dollar three-part asset-swap deal with Swiss peer Novartis, clearing the way for a big cash return for shareholders.The transaction, first announced in April 2014, saw GSK buy the bulk of Novartis' global vaccines business for $5.25bn and sell its oncology division for $16bn. The companies have also created a new consumer healthcare joint venture in which GKS will take control with a 63.5% stake.After tax, the net proceeds received by GSK were $7.8bn. It said that $1.5bn may have to be returned to Novartis if certain conditions relating to a drug trial are not met, but it reckons that the outcome will be positive after recent study results."As a result, following today's completion, GSK plans to use the transaction proceeds to fund the full amount of the previously announced capital return of £4bn to shareholders," the company said.GSK's chief executive Andrew Witty said the completion of the deal "represents a major step forward in the group's strategy to create a stronger and more balanced set of businesses across pharmaceuticals, consumer healthcare and vaccines".He said: "We will now be focused on rapidly implementing our integration plans to realise the growth and synergy opportunities we see in the new consumer healthcare and vaccines businesses."More details will be announced at an investor meeting on 6 May alongside GSK's first-quarter results. The company will also provide earnings guidance for 2015.GSK's shares were down 0.2% at 1,538.5p in early deals on Monday.