There are no publicly available sources or news reports to prove that the FDA has given any such assurance to Indian companies.
President Donald Trump had posted on Twitter a day after the Indian Government decided to relax the ban it had earlier imposed on the export of the drug Hydroxychloroquine in which he thanked India and Indian people for the decision on sending HCQ. Prime Minister Narendra Modi replied to Trump stating that India would do whatever it could to contribute to the efforts to contain the pandemic. However, we did not find any credible sources or news reports to prove that the FDA has given any assurance to Indian companies in this regard.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.