The one-for-115 offer only opened on January 16 and was due to close on March 6.
Catalyst has reached a 90.53% interest and will move to compulsory acquisition.
Vango holds the high-grade 1 million ounce Marymia gold project in Western Australia's Mid West, which Catalyst said would complement its operating Henty gold mine in Tasmania and large landholding in Victoria's Bendigo Goldfield.
Catalyst is already planning an upcoming exploration program at Marymia to follow up on high-priority targets and increase resources at the Trident and K2 deposits.
The company had also been in discussions with Toronto-listed Superior Gold, which holds the Plutonic mine, adjacent to Marymia.
Earlier this month, Catalyst said that while informal discussions were ongoing, it was unlikely any commercial agreement would be reached with Superior in the near future.
Catalyst shares last traded at $1.35, giving the company a market capitalisation of just over $130 million.