Shares of Verona Pharma plc closed up 31.7 percent on London's AIM (LSE:VRP) and spiked on Nasdaq (NASDAQ:VRNA) after top-line data showed that RPL-554 met its primary endpoint, producing clinically and statistically significant improvement in peak forced expiratory volume in one second (FEV1) at four weeks, compared to placebo, as a maintenance therapy in patients with moderate to severe chronic obstructive pulmonary disease (COPD). Peak FEV1 was improved at all time points over the four weeks of dosing, confirming the therapy's bronchodilator effect, according to Verona officials.