To reduce R by a factor of 2 by the use of a prophylactic drug, you'd need to have half of the population on a regime of the drug. It seems pretty obvious that did not happen if this kind of reporting is the most impactful there is. Just think of the logistics of trying to do that! India has a population of 1.4 billion.
On the other hand, if they only gave the snakeoil to e.g. a single digit number of millions of people the reduction in the number of infections would be imperceptible.
I think it is safe to suppose they or the associated medical authorities have observed a big enough benefit before making that claim.
But no, no concrete numbers, as I think there was not much of tracking the number of patients who were given the drug. May be it is because such numbers are not much of a value in terms of research data due to lack of controls.
Yes, example from two states.
https://indianexpress.com/article/cities/lucknow/uttar-prade...
https://www.news18.com/news/india/mortality-rate-much-lower-...
The testimony video in this page cites examples in many other countries https://covid19criticalcare.com/