The group specialises in the discovery and development of pharmaceuticals, focusing on research for the treatment of viral respiratory diseases, particularly influenza (flu).
It was one of the shares to sell from mid-February following a disappointing half year result.
However, BTA surged on Friday after it was awarded a US$231 million contract for the advanced development of its laninamivir drug.
Laninamivir is an influenza antiviral, which offers the ability to treat an influenza infection.
The contract will be fully funded over five years and is dependent on Biota Holdings achieving key milestones throughout the period.
BTA rocketed over 35% following the announcement, making it the best performer in the Australian share market.