The same hole hit a further 145.5m at 1.11% CuEq from 288m that remained open at depth.
Another drill hole intercepted 31.37m at 2.03% CuEq from 99m, where the hole entered Regulus ground.
The company has an 18,000m drilling programme underway, in collaboration with neighbouring gold miner Compañía Minera Coimolache SA, and is aiming to provide a "robust updated resource" by the end of the year.
Regulus has announced a series of lengthy mineralised intercepts in recent months, including 523.9m at 0.65% copper, 0.47g/t gold and 7.93g/t silver from 204.5m in September that sent its shares to a 52-week high of C$3.
The 2012 inferred resource was established by a previous operator and comprises 294.8 million tonnes at 0.48% copper, 0.36g/t gold and 10.2g/t silver.
Regulus CEO John Black said the company planned to increase the rig count to four or five once the rainy season ended in a month or so.
It had working capital of C$4.3 million (US$3.4 million) at the start of this year, which it said was sufficient to continue operations for at least the next 12 months.
Shares in the company closed up 4c on Friday to $1.85.