"So, large-cap biotechs have done well this year," he said. "We went back and actually analyzed what's driven that outperformance. Interestingly, the majority of the outperformance has been driven by new-product introductions and earnings upside because of leverage down to P&L.
"The multiple has actually contracted, which I think is kind of counterintuitive to what the public believes."
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Over the next year or two, the large-cap biotech sector is likely to see "robust data flow, new clinical data announcements, continued momentum in terms of the blockbuster product launches and the P&L leverage to drive earnings," Chai added.
"And in a way, we can envision a scenario where now sentiment, which we define as sort of the multiple, can catch up to fundamentals."
Chai said that his top three health-care stock picks are: Medtronic, which should do well regardless of how its proposed tax-inversion deal with Covidien turns out; pharmaceutical company Sanofi, and Tornier, a medical-device manufacturer that should benefit from a variety of factors, including recent restructuring and potential consolidation.