I begin with the assumption that you know the difference between product patent and process patent.India was only providing process patent for medicine before the TRIPS agreement.Now Because the TRIPS agreement provides that Patents shall be available in all fields of technlogy India is supposed to provide even product patent in medicines from 2005.(TRIPS DEADLINE).so now the Indian pharmaceutical industries must lay stress on basic research and development unlike earlier where they used the process of reverse engineering.
But how far is the indian pharmaceutical industries capable of r&d is a question yet to be answered.Moreover the infrastaructure and technology needed for R&D is also to be taken into account.The success of product regime will depend on the above conditions.
Read some Intellectual property jouranals for more information.Its an amazing area to read.
Hope this helps.
All the best for your dissertation :)