Regal said natural gas from the SV-59 well in Ukraine reached a flow rate of about 370,000 feet per day during initial testing.
"The well has now been hooked up to the gas processing facility and its performance will be monitored during a production testing program," the company said in a statement Thursday.
Regal is operating in the Mekhediviska-Golotvshinska and Svyrydivske gas and condensate fields in Ukraine.
The company said its aggregate production from its Ukrainian assets in January was 5.2 million cubic feet per day.
Regal said it planned to conduct a hydraulic fracturing campaign at the Mekhediviska-Golotvshinska field through March.
The Ukrainian government said last year there may be enough natural gas in shale reserve areas to satisfy the country's needs without imports. In January 2013, Shell signed a $10 billion contract to explore Ukrainian shale.