Par Pharmaceutical ( PRX), a maker of generic drugs, said that it entered into a supply and distribution agreement with AstraZeneca in the U.S. to distribute metoprolol succinate extended release tablets, which is substitutable for AstraZeneca's TOPROL-XL extended release tablets.

The New Jersey-based company began shipping metoprolol succinate extended release 25 mg tablets Tuesday.

TOPROL-XL is a beta1-selective (cardioselective) adrenoceptor-blocking agent, for oral administration, available as extended release tablets, the company said.

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