The stock slumped 10.61 per cent to settle at Rs 499.30 on BSE. During the day, it nosedived 14 per cent to Rs 480 - its 52-week low.
At NSE, shares of the company dipped 10.25 per cent to close at Rs 501.20.
The company's market valuation fell by Rs 748.28 crore to Rs 6,299.72 crore.
In terms of volume, 6 lakh shares of the company changed hands at BSE and over 48 lakh shares were traded at NSE during the day.
In a regulatory filing, Ipca Laboratories yesterday said the Geneva-based organisation that provides financial aid against AIDS, tuberculosis and malaria, has informed the company about its decision on Wednesday via a letter.
"In the light of the warning letter issued to the company by the USFDA on January 29, 2016, they (The Global Fund) have re-assessed the situation and following a risk consideration exercise, will not allocate any volume of Artemisinin based Combination Therapy (ACTs) to the company," Ipca Laboratories said.