Read more

July 14, 2022
2 min read
Save

Fourth mRNA dose produces ‘remarkable’ COVID-19 vaccine response in patients with ARDs

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

A fourth dose of a heterologous mRNA COVID-19 vaccine produced a “remarkable” humoral response in patients with autoimmune rheumatic diseases who had a poor response to a third homologous dose, according to data published in Rheumatology.

“We had previously reported that almost 20% of patients with autoimmune rheumatic diseases were still negative for anti-SARS-CoV-2 IgG and/or neutralizing antibodies (NAb) after three-dose homologous vaccination with CoronaVac,” Nadia E. Aikawa, MD, and Eloisa Bonfa, MD, of the rheumatology division at Faculdade de Medicina da Universidade, in Sao Paulo, Brazil, told Healio. “We, therefore, aimed to assess whether an additional fourth dose of an mRNA (BNT162b2) heterologous SARS-CoV-2 vaccine would improve immunogenicity in poor/non-responders ARD patients previously vaccinated with the third dose of CoronaVac.”

COVID variant
A fourth dose of a heterologous mRNA COVID-19 vaccine produced a “remarkable” humoral response in patients with autoimmune rheumatic diseases who had a poor response to a third homologous dose, according to data. Source: Adobe Stock

To examine the impact of a heterologous fourth vaccine dose among those with autoimmune rheumatic diseases, the researchers included patients aged 18 years or older who previously received a two-dose course of the Sinovac-CoronaVac vaccine between February 2021 and March 2021. Participants had also received a third dose as a booster shot in September 2021. For the purposes of the study, a poor response was defined as “an absence of nti-SARS-CoV-2 S1/S2 IgG or NAb,” the researchers wrote. A no-response was counted as an absence of both tests 30 days following the third dose.

Participants received a heterologous dose of the Pfizer-BioNTech vaccine (BNT162b2) 90 days following the third vaccine dose. Patients who had low disease activity were instructed to withhold mycophenolate mofetil and methotrexate after receiving the fourth vaccine dose.

In all, 164 patients classified as poor or non-responders were included in the analysis. The primary outcomes included humoral immunogenicity, assessed by the presence of IgG and NAb 30days after the fourth dose. Secondary outcomes included the geometric mean titer of IgG and the median NAb activity following the fourth dose.

According to the researchers, there were significant increases in the primary endpoints. After the fourth dose, the researchers noted an increase in IgG — 66.4% vs 95.1% (P < .001) — NAb positivity — 5.5% vs 83.5% (P < .001) — and geometric mean titer — 29.5 AU per ml vs. 215.8 AU per ml (P < .001). Meanwhile, 17.1% of patients remained non-responders.

Patients who remained negative for IgG after four doses were “more frequently” under rituximab (Rituxan, Genentech) (P = .001), the researchers wrote. Negative NAb was associated with older age (P = .015), rheumatoid arthritis (P = .002), systemic sclerosis (P = .026), LEF use (P = .016) and rituximab use (P = .007), they added.

“We have evidenced a remarkable humoral response to the fourth dose of heterologous mRNA SARS-CoV-2 vaccination in poor/non-responder ARD patients after the 3rd dose of an inactivated vaccine (CoronaVac),” Aikawa and Bonfa said. “A limitation of the study is the lack of a comparison group vaccinated with a 4th dose of homologous inactivated anti-SARS-CoV-2 vaccination.”