PROVIDED FURTHER that in respect of investigational medical device of Class A, data on clinical investigation may not be required, except in cases, where depending on the nature of the medical device, the Central Licensing Authority, for reason to be recorded in writing, considers such data necessary: PROVIDED ALSO that subject to other provisions of these rules, in case of medical device of which drugs are also a part, the submission of requirements relating to animal toxicology, reproduction studies, teratogenic studies, perinatal studies, mutagenicity and carcinogenicity may be relaxed in case of drugs already approved and marketed in India and supported by adequate published evidence regarding safety of the drug.