INNISHANNON-based MSD Ireland has applied to extend its current facility in the hopes of adding more than 100 jobs at its biopharmaceutical plant.
The move could see more than $100 million invested in the plant at Brinny, while recruitment for many of the new roles has already commenced.
It comes just one year after MSD Ireland outlined ambitious plans to increase its Irish workforce by 200 people across plants in Cork, Carlow and Tipperary.
The New Jersey-based pharmaceutical giant already employs more than 2,000 people in Ireland.
Barry Mulcahy, site lead at MSD Brinny, said the expansion is a positive commitment to MSD's operations in Ireland.
"We are delighted to announce the expansion of our production capacity at MSD in Brinny, which could potentially represent an investment of $100 million," he said.
"In recent years, our work has increasingly positioned us at the forefront of biopharma innovation globally, developing and manufacturing medicine for the world market, and growing our standing within the MSD network.
"[This] announcement represents a great vote of confidence in the future of our ongoing operations here in Cork."
The MSD site at Brinny has a long tradition of manufacturing excellence and a strong legacy in the biopharmaceutical sector.
The facilities at Brinny include an integrated facility for developing, testing and manufacturing biologics, with staff focusing on the fermentation, purification and sterile filling of biotech products.
This includes two of MSD's most successful treatments for oncology, hepatitis C and rheumatoid arthritis.
MSD has operated at Brinny for nearly 35 years and remains one of the region's largest employers.
Over 500 people are already employed there, with new roles in technical, engineering, quality and operations already advertised.
The current construction project and investment will take place over the next 18 months if approved by Cork County Council.