The megabillion-dollar deals with Novartis allow GlaxoSmithKline to "significantly expand" its world-leading vaccine business and create value for shareholders by selling its oncology treatments, GSK's CEO told CNBC on Tuesday.
Sir Andrew Witty's comments came after the announcement that Swiss-based Novartis is buying GlaxoSmithkline's cancer business in a deal valued at as much as for $16 billion, and selling its vaccine business to GlaxoSmithkline to $7 billion.
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"We've been a very newcomer to oncology in the last four or five years," Witty said in a "Squawk Box" interview. "Novartis is world No. 2. This was an opportunity to put our assets that we think are important medicines for patients in the hands of a company with a tremendous distribution network."
"That's what really allows, I think, this tremendous value to be achieved for our shareholders," he added—while also praising the new joint venture between his U.K.-based GlaxoSmithKline and Novartis on consumer health care.
The reverse is true in the vaccine transaction. "By bringing into our portfolio these Novartis vaccines—both today's and the possible future vaccines that they have under development—we really believe we're bringing them into family to make the most out of them in the over the next 10, 20, 30 years," Witty's said. "The vaccine business is a true annuity business."