April 14 (Reuters) - AstraZeneca Plc said on Tuesday that it would start a clinical trial to assess the potential of Calquence in the treatment of the exaggerated immune response associated with COVID-19 infection in severely ill patients.

Calquence is already approved for the treatment of adult patients with chronic lymphocytic leukaemia in the United States and a number of other countries.

The goal of the trial is to evaluate the effectiveness and safety of adding the drug to best supportive care to reduce mortality and the need for assisted ventilation in patients with life-threatening COVID-19 symptoms, the British drugmaker said.

(Reporting by Aakash Jagadeesh Babu in Bengaluru; editing by Patrick Graham)