Nestle SA said today it will acquire Novartis, maker of Boost and Resource nutritional supplements and Optifast diet products, for $2.5 billion. The deal does not include Novartis’s Gerber unit, which Nestle was earlier reported to be seeking. The deal is subject to approvals. It is expected to close in the second half of next year. The Novartis unit, based in Gland, Switzerland, employs about 2,000 workers. Vevey, Switzerland-based Nestle, whose U.S. headquarters are in Glendale, said those workers will join its company.