Shares of Mesoblast plummeted by 58.3% to A$0.455, marking the worst performing day for the stock if the losses are maintained.

Mesoblast, the drug developer, has received a response from the US FDA with regards to its Biologics License Application for its drug remestemcel-L, which is used for the treatment of pediatric steroid refractory acute graft versus host disease.

The FDA has requested for additional data to endorse the approval for the drug in the market.

In response, Mesoblast announced it will undergo a targeted, controlled study to acquire the necessary data to bolster the approval.

The resulting slump marked the lowest performance for the stock since August 10, 2005.

Despite being the largest percentage loser on the ASX All Ordinaries index, the stock has managed a 25.3% rise for the year as of the last closing.

Mesoblast (ASX:MSB) is a healthcare company specializing in the development of cell-based therapies.