Convalescent Plasma May Be an Option for Life-Threatening Pediatric COVID-19

By Marilynn Larkin

September 17, 2020

NEW YORK (Reuters Health) - A small case series suggests convalescent plasma (CP) may be safe and "possibly" effective in children with life-threatening SARS-CoV-2- associated acute respiratory distress syndrome.

"As (the treatment) is experimental, well-designed rigorous randomized pediatric trials are needed," Dr. David Teachey of Children's Hospital of Philadelphia told Reuters Health by email.

As reported in Pediatric Blood and Cancer, the researchers treated four patients ages 14-18 with CP. Patients were considered for the treatment if they met U.S. Food and Drug Administration guidance for life-threatening disease.

Donors were eligible if, per American Red Cross guidelines, they were positive for SARS-CoV-2 on a laboratory test and were at least 14 days from symptom resolution with a repeat negative test, or at least 28 days from symptom resolution without a repeat test result at the time of plasma collection.

Donor antibody levels and recipient antibody response were measured before and after CP infusion.

All patients were intubated; two required extracorporeal membrane oxygenation. None had multisystem inflammatory disease. They received all available plasma from the donors (200-220 mL). One patient received 2 mL/kg, and the other three received 4 mL/kg.

CP infusion was not associated with antibody-dependent enhancement and did not suppress endogenous antibody response; it was "safe and possibly efficacious," according to the authors. "CP may be of greatest benefit for patients who are early in their illness and have not yet generated endogenous antibodies, and when the infused plasma has a high antibody titer," they suggest.

Dr. Teachey said, "We are discussing internally the best next steps. They definitely need to be multi-institutional, and ideally we need randomized trials. With the field moving as quickly as it is, we will likely await some of the data from adult randomized trials to guide our next steps."

Dr. Miguela Caniza, Director, Infectious Diseases Program at St. Jude Global in Memphis, has managed children with COVID-19 and provided expert advice to colleagues at international sites regarding such children. "At St. Jude, none of the children with COVID-19 were managed using CP transfusion," she told Reuters Health by email. "But despite the lack of pediatrics, because of the safety profile, we have CP transfusion listed as a resource to use in situations of progressively worsening pulmonary conditions, either together with an antiviral or as alternative to antiviral."

Use of preformed antibodies, known as passive immunization, is an established pediatric practice in diseases such as botulism, cytomegalovirus and hepatitis B, she noted. "For COVID-19, information is emerging regarding what types of antibodies are the most effective, and what level of antibody should be optimum. We will have more information as we go."

"If CP transfusion is used," she added, "the care provider must be aware of standard risks, such as those related to infections transmitted by blood such as HIV, hepatitis B and C. But currently, safety of blood products is very high, and the risks of these infections are very low. Other risks are reactions to serum constituents and risk for acute lung injury, which are also rare. Another important consideration is the extra fluid that a severely sick patient might need to receive."

SOURCE: Pediatric Blood and Cancer, online September 4, 2020.