(Updated)
Amgen says there is no truth to the rumor that the FDA is investigating post-marketing reports of serious brain infections in patients taking PCSK9 inhibitors.
The Amgen statement was in response to this anonymous post on CafePharma:
“The FDA informed Amgen and Regeneron today that there have been a number of post marketing reports of serious brain infection following the administration of PCSK9 agents. While they have not indicated any causal effect they have asked both manufacturers to prepare to attend a briefing at FDA after the new year. The agency has not indicated if they will issue any warnings or updates to the prescribing community as yet, there are 7 reports for repatha and 5 for pralulent. Amgen R&D is working thru the weekend to prepare for the meeting. It’s not clear if the company will be sharing this with the field at this point. As I get updates I will share.”
I asked Amgen to respond to the post. An Amgen representative, Trish Hawkins, sent the following statement:
With respect to any post-marketing adverse event reports beyond what is included in the Repatha labeling, we are not aware today of any outreach or contact to us from the FDA.
I have also reached out to the FDA, Sanofi/Regeneron, and investigators leading the large outcomes trials with Amgen’s Repatha and Sanofi/Regeneron’s Praluent.
Update, December 20, 12:18 PM, 12:57 PM:
I have now received a similar statement from Sanofi and Regeneron:
Regeneron and Sanofi have not received any notifications from the FDA on this topic nor have we received a request to attend a meeting.
There has been an active discussion on Twitter suggesting that the Amgen statement does not preclude the possibility that the FDA has asked for a meeting or for more information about some other adverse events. Some observers speculate that these could potentially be neurocognitive adverse events, since there has been a very small signal for this problem in previous studies. I have asked Amgen and Sanofi/Regeneron for a clarification on this point.
It is worth mentioning here that a small neurocognitive signal now would not be entirely unexpected, since this is a controversial new class of drugs and neurocognitive events already occur at a high rate in the population taking the drugs. It is extremely difficult to interpret a few reports in the FDA’s adverse event data base. By contrast, the “serious brain infection” alleged in the original CafePharma post would be more likely to raise a red flag, because it is highly unusual and has not been a topic of previous concern with the PCSK9 inhibitors.
12:57 PM Update: Asked to clarify their statement, Sanofi/Regeneron wrote:
As stated, we have not received any communication/notification from the FDA.
Update, Monday, December 21, 2:40 PM–
I asked the FDA for a response to this story. Here is what they sent me:
The FDA doesn’t have anything to add, and would wouldn’t typically comment on anonymous posts.
3:10 PM Update:
Asked for further clarification the FDA said that it was continuing to conduct “routine postmarking safety surveillance” for the drugs:
The FDA continues to conduct routine postmarketing safety surveillance for the PCSK9 drugs, as it does for all approved products.
Perhaps I’m naive, but I think this statement means that this entire episode has been much ado about nothing. Time will tell.
The key is the details. Were these primary brain infections (rare, very concerning) or secondary (not uncommon, as in endocarditis). Were the bugs common flora from the mouth (less concerning) or skin flora (more concerning with an injectable) or rare pathogens (even more concerning). How strong are these diagnoses? Were they related LDL-C levels? Has this been seen with other injectable mABs? Has anyone even looked?