Amgen said the deal, which has been approved by the boards of directors of both companies, is expected to close in the third quarter.
Alantos' lead candidate is ALS 2-0426, a DPP-IV inhibitor in phase 2a studies for the treatment of type 2 diabetes.
"We are pleased to add this clinical stage DPP-IV inhibitor to our growing portfolio of therapeutics for the treatment of metabolic diseases," said Roger Perlmutter, Amgen's executive vice president for research and development.
Perlmutter said Amgen also plans to advance Alantos' compounds that inhibit matrix metalloproteinase-13, or MMP, an enzyme that plays a role in causing the damage associated with osteoarthritis. The MMP inhibitors are currently in preclinical development.