Although it is piece of news from 2012, but it cannot be say enough, that FDA officially accepts submissions in R.
“The FDA does not endorse or require any particular software to be used for clinical trial submissions, and there are no regulations that restrict the use of open source software (including R) at the FDA. Nonetheless, any software (R included) used to prepare data analysis from clinical trials must comply with the various FDA regulations and guidances. The R Foundation helpfully provides a guidance document for the use of R in regulated clinical trial environments, which provides details of the specific FDA regulations and how R complies with them.”
The details can be found in here.