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Ask the Doctor: What is the average antibody response rate for the CLL patient who have had two Moderna shots and a Moderna booster?

This content was current as of the date it was released. In science and medicine, information is constantly changing and may become out-of-date as new data emerge.


What is the average antibody response rate for the CLL patient who has had two Moderna shots and a Moderna booster? I was diagnosed with stage Zero CLL in 2018, and I am still in watch and wait. I have mutated IgHv. Are there any trials gathering this data in order to draw some conclusions? Could I be a participant?

Answer: Honestly, the antibody responses for CLL patients are all over the charts, so it would be impossible to predict in your case. However, if you are still in watch and wait you have the best odds of having responded in some way. We would highly recommend you talk with your CLL treating physician to see if he/she would be willing to order a COVID-19 spike protein antibody titer for you to see whether or not you responded. If he/she does not want to do that, you can go through any LabCorp and request it be drawn. You just have to create an online account and pay $10 for the test. Here is a link to their website where you can find more information:

Here is what we do know about antibody response rates and CLL:

  • Only 40% of all CLL patients had detectable antibodies after vaccination
  • Of that 40% who did have any detectable response:
  • 55% of those patients were in watch and wait and had never received any treatment
  • If a CLL patient had received any sort of previous treatment, their chance of responding to the vaccine was only 16%
  • 79% of those patients were in remission from their CLL

We also know that:

  • Any anti-CD20 antibody therapies (such as rituximab) or being on any BTK inhibitors (such as ibrutinib) was associated with an impaired vaccine response
  • There needs to be at least NINE months that pass after the last B-cell directed treatment to have an improved antibody response

You can go to and type in CLL and COVID for the key terms. It looks like there is one trial at City of Hope in California that is still recruiting. Here is the link to those search results: