Merck (MRK -3.1%) slips today after its Q4 fails to impress amid a decline in net sales. The...

|About: Merck & Co Inc. (MRK)|By:, SA News Editor

Merck (MRK -3.1%) slips today after its Q4 fails to impress amid a decline in net sales. The company blames the earnings drop on patent expiry for its asthma drug Singulair, adding that the loss of its patent in the U.S. and Europe will be 2013's biggest revenue challenge. The company also announced a potential year-long delay in seeking regulatory approval for its new osteoporosis drug odanacatib, citing the need for additional safety and efficacy data from an ongoing clinical trial. Read the full transcript of the earnings call here: Earnings Call Transcript.