Do you know off hand how big their shelf is? I would speculate on ITMN or VRUS. The former because they have acquired a couple (private) companies with targets their and the timing would let Gilead pretty much launch the drug and ITMN doesn't have much (anything) else right now. Not to mention that Warburg probably would be happy to cash out. Plus its near term revenue. VRUS seems like a second natural candidate but that doesn't quite give the immediate gratification :-).
The Gilead PR does specifically cite repayment of existing debt and buying back shares. No mention of M&A. Gilead does fairly regularly make deals, including Calistoga recently which I think will turn out well.
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