Why is Ramdev's Coronil drug receiving backlash from all sides?

In wake of yoga guru Ramdev announcing a self-proclaimed Covid-19 medicine, Rajasthan Health Minister Raghu Sharma warned that stringent action shall be taken against those propagating and endorsing any kind of medicine for coronavirus without following due norms. Maharashtra Home Minister even called it a fake medicine. Meanwhile, director of the institute where the trial of Coronil supposedly took place has already backtracked on his support for the drug. What is the story behind the Coronil controversy?