Alexion in Athlone is applying for planning permission to develop 20 new car parking spaces at their premises in Monksland.
The international pharmaceutical company also wants to redesign five existing parking spaces as well as a truck manoeuvring area.
Alexion built a new manufacturing facility on its site in recent years doubling its original workforce of 50.
It also has a manufacturing facility in Dublin.
The US company specialises in the development of drugs for rare diseases and conditions.
It announced in April that it was enrolling patients globally as part of a study on treatments for Covid-19.