Factbox - M&A frenzy transforming global pharma

(Reuters) - Several multi-billion dollar deals and offers announced over the past few weeks have made 2014 the busiest year for healthcare acquisitions, according to Thomson Reuters data.

Bayer's $14.2 billion acquisition of Merck's consumer care business on Tuesday pushed the value of pharmaceutical M&As to $239.1 billion so far this year.

Healthcare companies, under pressure from tougher reimbursement regulations in developed countries, are adding scale, picking up specialised expertise and shedding non-core businesses.

Here's a list of some of the major deals and offers this year:

MAY

May 6 - Merck & Co Inc (MRK.N) agrees to sell its consumer care business to Germany's Bayer AG (BAYGn.DE) for $14.2 billion.

May 2 - Pfizer Inc (PFE.N) raises its offer for AstraZeneca Plc (AZN.L) to 63 billion pounds ($106 billion), but the British company promptly rejects the proposal, which would create the world's biggest pharmaceuticals company.

APRIL

April 30 - Sanofi SA (SASY.PA) is looking to sell a portfolio of older drugs that could fetch $7 billion to $8 billion, Reuters reports, citing people familiar with the matter.

April 28 - Allergan is preparing to approach Shire Plc (SHP.L) about a potential takeover, even though the Irish drugmaker rebuffed a previous overture, Reuters reports, citing sources familiar with the matter.

Forest Laboratories Inc says it will buy Furiex Pharmaceuticals Inc (FURX.O) for up to $1.46 billion, including milestone payments.

April 25 - U.S. generic drugmaker Mylan (MYL.O) makes new and improved bid for Meda (MEDAa.ST), valuing its Swedish rival at around $9 billion including debt, Reuters reports, citing a source familiar with the matter.

April 24 - Zimmer Holdings Inc (ZMH.N) says it would buy rival orthopaedic products maker Biomet Inc (LVBHAB.UL) for more than $13 billion.

April 22 - Canada's Valeant Pharmaceuticals International Inc (VRX.TO) and activist investor Bill Ackman makes an unsolicited $47 billion bid to buy Botox maker Allergan Inc (AGN.N). The bid prompts Allergan to adopt a one-year stockholder rights plan to give it more time to consider takeover proposals.

Novartis (NOVN.VX) and Britain's GlaxoSmithKline (GSK.L) agree to trade more than $20 billion worth of assets to bolster their best businesses and exit weaker ones. Novartis also says it would sell its animal health arm to Eli Lilly (LLY.N) for about $5.4 billion in cash.

April 7 - Specialty pharmaceuticals company Mallinckrodt Plc (MNK.N) says it will buy drugmaker Questcor Pharmaceuticals Inc (QCOR.O) for about $5.6 billion to gain access to its multiple sclerosis drug, Acthar Gel.

FEBRUARY

Feb. 24 - German drug firm Bayer clinches a $2.9 billion deal to take over Norwegian cancer drugmaker Algeta (ALGETA.OL) after being tendered 92.17 percent of the shares in a cash offer.

Feb. 18 - Generic drugmaker Actavis Plc (ACT.N) says it will buy Forest Laboratories Inc (FRX.N) for about $25 billion in cash and stock, giving it a major focus on higher-margin, branded treatments for Alzheimer's, hypertension and other disorders.

Feb. 11 - Mallinckrodt says it will buy pain drug maker Cadence Pharmaceuticals Inc (CADX.O) for about $1.3 billion to expand in the hospital market.

Feb. 3 - Britain's Smith & Nephew Plc (SN.L) says it will buy ArthroCare Corp (ARTC.O) for an agreed $1.7 billion in cash to strengthen its treatments for sporting injuries, an area growing faster than its main replacement hips and knees business.

JANUARY

Jan. 16 - Johnson & Johnson says it will sell its ortho clinical diagnostics unit to buyout firm Carlyle Group LP (CG.O) for $4.15 billion, shedding a slow-growing business to focus on more lucrative products.

Jan. 8 - Forest Laboratories Inc says it will buy specialty pharmaceutical maker Aptalis from private equity firm TPG Capital for $2.9 billion.

(Compiled by Esha Dey and Sriraj Kalluvila in Bangalore)