Illumina (Nasdaq: ILMN) has rejected a $5.7 billion, or $51 per share, buyout offer from Roche Holdings. www.illumina.com

CVC Capital Partners has agreed to sell Eastern European brewer StarBev LP to Molson Coors Brewing Co. (NYSE: TAP) and StarBev management for €2.65 billion. StarBev generated around €700 million in 2011 sales with €241 million in EBITDA. Nomura International managed the process for CVC. www.cvc.com

ANV Holdings BV has agreed to acquire the Lloyd’s operations of Bermuda-based Flagstone Reinsurance Holdings for around $48 million in cash. Ontario Teachers’ Pension Plan Board is helping ANV finance the deal.

Cairn Energy, a UK-based energy exploration company, has agreed to acquire Agora Oil & Gas for $450 million.

GenBand, a Plano, Texas-based provider of IP infrastructure and application solutions, has acquired Aztek Networks, a Boulder, Colo.–based provider of switch consolidation and network migration solutions. No financial terms were disclosed. GenBand has raised around $40 million in VC funding from firms like Invesco Private Capital, Siemens Venture Capital, Sevin Rosen Funds, HLM Venture Partners, Trellis Partners, TI, Venrock, Star Ventures, Wheatley Partners and Oak Investment Partners. Aztek had raised nearly $7 million from Grotech Ventures, Sequel Venture Partners and Telecom Development Fund. www.genband.com

StemLine Therapeutics Inc., a New York-based biopharma company focused on both cancer stem cells and tumor bulk, has filed for a $50 million IPO. It plans to trade on the Nasdaq under ticker symbol STML, with Oppenheimer & Co. and JPM Securities serving as co-lead underwriters. Shareholders include Madoff Family LLC and Neuberger Berman Athyrium. www.stemline.com

Theravance Inc. (Nasdaq: THRX) has agreed to sell 10 million newly-issued shares to existing backer GlaxoSmithKline PLC at nearly $21.29 per share. www.theravance.com

Ventas Inc. (NYSE: VTR) has completed its previously-announced acquisition of fellow healthcare property company Cogdell Spencer Inc. for up to $770 million (including assumed debt), or $4.25 per share. Centerview Partners and Morgan Stanley advised Ventas, while Citi advised Cogdell Spencer. www.ventasreit.com

Want deal news in your inbox each morning? Get Term Sheet!