Replies to post #28800 on Biotech Values

[Biowatch]

How are Class I and Class 2 defined?

How does the FDA define a Class 1 and Class 2 letter? What does it mean to get one versus the other?

Most companies who get an approvable letter usually say they need further discussions with the FDA to find out what they need to do, but the NBIX webcast was exceptionally brief on this issue.

[jellybean]

David,

Here is a link to the "approvable letter" sent to Insmed back in September 2005. I use that term because that is how the FDA has the letter labeled in its files.:

http://www.fda.gov/cder/foi/nda/2005/021884_s000_Iplex_ApprovBle.pdf

No where in the letter does it state a "class" for the decision. In fact, I have not been able to find that information in any of the documents for the Insmed NDA. What I do see is that the FDA gave 10 days for the company to inform the agency of what action would be taken. The FDA then gave up a thumbs up to the proposed action and a new PDUFA date set. I remember the Insmed cc regarding the approvable notice and Geoff Alan stating that the response time would be quick but that he a classification had not been given -- people were skeptical about his "evasiveness" but he was being honest.

Maybe the FDA is not as upfront or straightforward as one would hope. It appears that there is a time period between the receipt of the "approvable letter" and the FDA's decision as to its classification.