Ligand Pharmaceuticals Inc. (LGND) announced plans to buy Metabasis Therapeutics Inc. (MBRX) for $3.2 million in cash plus four tradable contingent value rights for the biopharmaceutical's stockholders.

The planned $3.2 million deal, less about $1.3 million in net liabilities at closing, includes four contingent value rights for each former Metabasis share, for a total of about 140.6 million CVRs.

Upon closing, Ligand expects to spend at least $8 million in new research and development funding on Metabasis programs over the next three and a half years. Metabasis has a pipeline includes clinical-stage product candidates for the treatment of metabolic diseases such as diabetes and hyperlipidemia.

The Ligand and Metabasis boards already voted in favor of the transaction. Stockholders of Metabasis representing about 29% of outstanding shares of Metabasis also supported the deal.

Ligand doesn't expect the takeover to affect its 2009 results. In 2010, the required cash payment is projected to be largely offset by the potential receipt of a cash milestone from Roche Holding AG (RHHBY, ROG.VX) for the advancement of its program for hepatitis.

The company's planned acquisition of Metabasis follows its August deal for cash-strapped drug developer Neurogen Corp. (NRGN).

Metabasis' shares were down 1.1% to 90 cents in premarket trading, while Ligand's stock was inactive at $1.91.

-By John Kell, Dow Jones Newswires; 212-416-2480; john.kell@dowjones.com