GlaxoSmithKline and Novartis said yesterday they had completed a series of asset swaps worth more than $20 billion that will reshape both drugmakers. GSK is forming a consumer health joint venture with Novartis, while at the same time buying the Swiss company's vaccines business and divesting its cancer drugs portfolio to Novartis. The two companies originally announced the transactions in April 2014 to bolster their best businesses and exit weaker ones as the drugs industry contends with healthcare spending cuts and increased generic competition. GSK, which now plans to return $6.2 billion to shareholders, said it would provide an in-depth view of its prospects at an investor meeting to be held on May 6.