Boniva, known generically as ibandronate, is taken once a month to treat or prevent osteoporosis in women after menopause.

Mylan Pharmaceuticals Inc and privately held Apotex Inc and Orchid Healthcare are the manufacturers that have gained approval to make generic 150-milligram ibandronate tablets, the FDA said.

Ibandronate is in a class of medications called bisphosphonates, which help increase bone mass and reduce the chance of having a spinal fracture.

An estimated 10 million Americans over the age of 50 have osteoporosis, and another 34 million have low bone mass, according to the National Osteoporosis Foundation.

Mylan shares closed Monday down 2 cents at $22.87 on the Nasdaq.

(Reporting By Susan Kelly; Editing by Tim Dobbyn)

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