Booster recs after 5 vaccine administration snd Evusheld

[skipro]

Hi

I have relapsed CLL and immune globulin Deficency.

I had no antibody response to 4 separate Pfizer vaccinations 12/28/20, 1/20/21, 4/30/21 and 5/20/21.

I get IVIG and had some antibodies on 8/20/21

I received vacation # 5 FULL Moderna 11/23/21 and had a response of 600 on a scale of 0-2500.

I received Evusheld 12/40/22 and the second dose Evusheld 2/20/22.

I have heard mixed reviews on a subsequent Moderna BOOSTER would come at 6 weeks post Evusheld and 5 months post Vaccination #5?

Does anyone have evidence based recs about this 6th vaccination dose or booster?

Thx

Dr Mike Green

[AussieNeil Administrator]

Hi Mike,

Unfortunately you are ahead of documented studies into the booster recommendations with CLL. What evidence we have comes from the US Leukemia and Lymphoma Society (LLS) trials and Israel's experience.

With respect to timing of boosters, different countries are gradually recommending variously. The reasons for this are various and include factors such as a different mix of vaccinations, variations of roll-out times and previous booster recommendations and most importantly, the impact of new variants and the anticipated benefit from recommending boosters and the booster timing. That circulating variant consideration also influences the timing of a booster after Evusheld, depending how well the Evusheld antibodies hold up against what's circulating where you live. The only official recommendation is to have a vaccination booster at least 2 weeks before Evusheld. With the Evusheld monoclonal antibodies in your blood stream and tissues, you'll have the varying complications of a reducing amount of circulating antibodies over time, varying effectiveness in preventing infection depending on whether you risk exposure to BA.1, BA.2, XE or whatever comes next and the dampening effect of those circulating antibodies on boosters. The Evusheld antibodies would be expected to neutralise the spike protein provided by the boosters, lessening the likelihood of benefiting from the booster, with that effect waning over time.

Neil

[bennevisplace in reply to AussieNeil]

That was a great synopsis Neil - it was complicated! The subsequent predominance of Omicron BA.5, which Evusheld seems to neutralise only very weakly, while the new bivalent vaccines seem to be effective, makes the issues clearer - until the next wave, driven by the next variant.