This week I caught up with my colleague and fellow SEND obsessive, Mike Wasko. I asked him for his opinions on the FDA feedback letters that sponsors receive after IND submissions. Specifically, his thoughts on their importance and impact – Here’s what he had to say:

Whenever a sponsor receives a letter or feedback from the FDA, the initial knee jerk response of many is to panic.  I’d say approximately 95% of the time, there is no need to panic. A little context of what these letters/reports are, and why the FDA are providing them may be helpful.

When SEND first started being required, the industry desired feedback from the FDA, and to this date, it still does to aid with the moving target of best practices and new standards. In the first few years of the SEND requirements, only the inner circle of the SEND industry was able to get feedback on quality and preferences. Granted, extensive validation rules did not exist at this time, so the feedback was even more important. But this feedback only reached the participants (approximately 50 people) of the CDISC SEND Face to Face meetings with the FDA, which occur twice a year. To increase communication and feedback to the industry, the FDA introduced some new communication methodologies. First, they would start having SBIA (CDER Small Business and Industry Assistance) webinars to help give feedback to the community on submissions, areas of improvement, SEND at the FDA and more. The second was study specific feedback to sponsors. The assessment was provided by the edata team at the FDA, as part of the Kickstart services. The assessment included automated and manual review of the send package for compliance, rules, recommendations, consistency, and ensure the agency can reproduce the summarizations in the actual study report. 

So, the next logical question for sponsors is “what do I have to do” if you’ve received a letter of feedback from the FDA. Most of the time, nothing. The document itself states something along the lines of no action or response is needed unless specified. It also states the feedback is to aid in improving future submissions of SEND datasets. Great news, right?  Yes, if there are things that are very wrong, the report will indicate which findings must be fixed and a new package submitted. Industry would be well advised to implement the recommendations so that future studies don’t have similar issues. With that said, the question still exists, that if one receives such feedback from an IND submission, should you fix it for the NDA submission? The time between and IND and an NDA can be many years, and with the rate of change in SEND in terms of best practices, updating implementation and when to update is really a sponsor decision. My recommendation would be to implement the changes recommended at IND in order to ensure a smoother review at NDA. It is helpful to share the feedback with your SEND teams and your SEND partners/CRO/vendors to help the whole industry advance and improve. Especially since it is easy to apply small amounts of changes to your SEND practices as you go, rather than many all at once.

I thought that was a great update for Mike to share.

As usual, feel free to join the conversation and drop me a note at

Till next time,


Published by Marc Ellison

Self-confessed SEND nerd who loves geek-ing out about everything to do with SEND. Active CDISC volunteer and member of the CDISC SEND extended leadership team. Director of SEND solutions at Instem responsible for all our industry leading SEND products and services.