The Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) met today to discuss the blood clots’ issue and offered guidance on heparin usage in these cases.
After recommending a pause on the Johnson & Johnson COVID-19 vaccine on Tuesday, no further US federal government guidance is forth coming for the moment.
In a meeting that ran over four hours this afternoon, the CDC’s ACIP decided not to vote on making additional pause recommendations. Instead they decided to meet in the near future to vote—likely in the next week—with the assumption it will have more data presented to it on potential cases of serious adverse events for cerebral venous sinus thrombosis (CVST) in combination with low-levels of platelets in the blood (thrombocytopenia).
This non-decision is paramount to punting on recommendations and assumes the pause stays in place for now.
The CDC meeting began by reviewing the data of the adenovirus vaccines starting with the AstraZeneca COVID-19 vaccine and looking at serious adverse events for cerebral venous sinus thrombosis (CVST) in combination with low-levels of platelets in the blood (thrombocytopenia)
By comparison, the AstraZeneca COVID-19 vaccine has seen several more cases of these adverse events and fatalities after vaccination.
Aran Maree, MD, Chief Medical Officer, The Janssen Pharmaceutical Companies of Johnson & Johnson presented information about some of the COVID-19 vaccine trials including its phase 3 trial, which had a total of 43,783 vaccinations, and after 28 days there were 4 cases of Deep Vein Thrombosis (DVT) in the vaccine arm and 2 in the placebo group. Interesting to note, of the 272,438 Janssen COVID-19 vaccinations in South Africa there were no reported cases of CVST.
With the Janssen vaccine, they have had 6 cases of severe adverse effects regarding blood clots in the post-authorization period captured from March 19 through April 12. Maree went through the diagnosis, treatment, and updates on the patients' conditions.
These cases occurred in white females and none of the patients were pregnant or post-partum. The median age was 33, and none of the people had coagulation issues. Initially, the features were headache, chills, but no obvious patterns of risk factors.
The ACIP said additional cases might be diagnosed in the next week to two weeks.
The vaccine adverse event reporting system (VAERS) showed 6 cases of CVST with the Janssen vaccine; the Moderna had 3 cases of CVST with normal platelets—which is an important distinction—and no reports of CVST for the Pfizer-BioNTech vaccine.
One important aspect that came out of today’s meeting was the recommendation for clinicians to not treat patients with thrombotic events and thrombocytopenia with heparin unless heparin-induced thrombocytopenia (HIT) testing is negative.
The CDC put 2 questions before the ACIP to discuss:
During the deliberation, ACIP members of the panel discussed whether they had enough data to continue the pause of the vaccine.
“There will never be perfect data,” Grace Lee, MD MPH. (ACIP, VaST Co-chair) said, but she discussed the importance of minimizing the risk.
When it was decided to not vote today, the meeting ended abruptly without a specific timeline for a follow-up meeting. There is an already scheduled meeting set for May, but it remains to be seen if they will convene before then as alluded to, or if they will wait.