A single-centre, observational study to evaluate immune response to Covid-19 vaccines in immunocompromised patients with haematological disorders (COVAC-IC)
Authors:   COVAC-IC investigators, Chandra Deepak , O’ Mara Lucy , Bailey Lucy , Aspey Mathew , Asaduzzaman Md , Banavathi Krishna , Lea Simon , Bowler Rob , Prasangika Jayasekara , Ogbolosingha Aviva , Goddard Sarah , Phillips Neil , Wasim Fauzia , Badugama Buddhika , Kamran Nausheen , Perera Kumari , Bano Fehmida , Pillai Srinivas , Dyer Peter , Aquil Muzna , Remegoso Alda , Lee Judith , Watts Keira , Karunanithi Kamaraj 
Published: November 2022

Objective

To evaluate immunological response to Covid-19 vaccines in immunocompromised haematology patients and compare with immunocompetent healthy controls

Design

We compared total Anti-SARS-CoV-2 spike antibody and T cell response in 45 immunocompromised haematology patients with 30 healthy adults following 2 doses of Covid-19 vaccine for 3 -5 months at 30 day intervals

Setting

Single Centre, University Hospital, United Kingdom, March 2021-December 2021

Main Outcome measures

Peak quantitative total spike-specific antibody and cellular responses

Results

We found

Non - significant difference in T cell and total Anti-SARS-CoV-2 S antibody response between study and control group patients

Six (13%) study group participants did not have detectable Total Anti-SARS –Cov-2 S antibodies at any time point throughout the study monitoring period.

Three (7%) of the study group participants had no response, even after additional booster doses of Covid-19 vaccine.

All (100%) of the control group had detectable Anti-SARS-Cov-2 S antibodies after 2 doses of Covid-19 vaccine.

No participant died or was hospitalised due to severe Covid-19 infection during the study period. This included study group participants who had no antibody response at any time point.

Conclusions

Though there was a non - significant difference in T cell and total Anti-SARS-CoV-2 S antibody response between immunocompromised patients and healthy controls this did not result in any severe infection or Covid-19 related mortality in our study cohort. We did not identify any patient-specific factor (age, gender), specific haematological condition or treatment as determinant of response. Covid-19 vaccination was well tolerated without major side effects in both groups.

What was already known about this topic

prior to starting this study there were no studies to confirm immunological response following Covid-19 vaccination in immunocompromised haematology patients. During the conduct of our study there have been publications from researchers confirming blunted serological response in 62-66% of immunocompromised haematology patients compared to 74-95% in healthy controls.

What this study adds

Our study did not identify a significant difference in serological or T cell response between immunocompromised and healthy groups. Though 13% of immunocompromised patients had no response to Covid-19 vaccination none of them suffered from severe Covid-19 infection. We believe T cell response to Covid-19 vaccination has an important role in providing protective efficacy against Covid-19.