Merck's (MRK 0.07%) shareholders got some good news today. In addition to seeing the company's shares climb by about 5.3% -- as the broader stock market rebounded a bit after a disastrous start of the week -- Merck announced positive results from two phase 3 clinical trials. The trials in question -- dubbed COUGH-1 and COUGH-2 -- investigated the efficacy of Gefapixant, an orally administered drug, as a treatment for refractory or unexplained chronic cough.

Patients who took 45 milligrams of Gefapixant twice a day experienced a statistically significant decrease in their "average hourly cough frequency" after 12 weeks (which constituted the COUGH-1 clinical trial) and 24 weeks (which constituted the COUGH-2 clinical trial) compared to those who took a placebo. It is also worth noting that a third group of patients, those who took 15 milligrams of Gefapixant twice a day, did not experience a statistically significant decrease in their average hourly cough frequency.

The pharma giant said the clinical trials would continue for "long-term follow-up" as it collects additional data. 

Woman coughing.

Image source: Getty Images.

Gefapixant could become the first approved treatment for chronic cough

Chronic cough, which is defined as a cough lasting more than eight weeks, is a condition that affects about 10% of the population. Also, in up to 46% of cases of chronic cough, no treatable causes of the condition can be identified. There are currently no treatments approved for chronic cough by the U.S. Food and Drug Administration (FDA). Merck did not provide any timeline for the submission of Gefapixant for review to the FDA, and this product probably won't hit the market anytime soon.