(Reuters) -Apollo Global Management ( APO ) submitted a fresh bid within the last week to take pizza chain Papa John's International private at $64 per share, according to people familiar with the matter.

The situation is fluid and no deal is guaranteed, the sources said, requesting anonymity as the situation is private. StreetInsider first reported the offer on Monday.

Reuters reported in June that Apollo and Irth Capital Management submitted a joint offer for the company at just above $60 per share. Multiple activists are also circling the pizza chain, according to sources.

Papa John's and Apollo declined to comment.

Private equity firms have snapped up restaurant chains in recent years, from Subway to Dave's Hot Chicken to Jersey Mike's. 

Papa John's has a market value of about $1.6 billion and its stock is up by roughly 18% so far this year. While the company's sales rose 4% to $529.2 million in the second quarter ended June 29 over the same time last year, its profits slid by close to 23% to $9.7 million.

Founded in 1984, the pizza chain is co-headquartered in Atlanta, Georgia, and Louisville, Kentucky. It has close to 6,000 restaurants in roughly 50 countries and territories.